1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2018 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
25 #include "signals-state-save-restore.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
29 #include "nat/gdb_ptrace.h"
30 #include "nat/linux-ptrace.h"
31 #include "nat/linux-procfs.h"
32 #include "nat/linux-personality.h"
34 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
46 #include "filestuff.h"
47 #include "tracepoint.h"
50 #include "common-inferior.h"
51 #include "nat/fork-inferior.h"
54 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
55 then ELFMAG0 will have been defined. If it didn't get included by
56 gdb_proc_service.h then including it will likely introduce a duplicate
57 definition of elf_fpregset_t. */
60 #include "nat/linux-namespaces.h"
63 #define SPUFS_MAGIC 0x23c9b64e
66 #ifdef HAVE_PERSONALITY
67 # include <sys/personality.h>
68 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
69 # define ADDR_NO_RANDOMIZE 0x0040000
77 /* Some targets did not define these ptrace constants from the start,
78 so gdbserver defines them locally here. In the future, these may
79 be removed after they are added to asm/ptrace.h. */
80 #if !(defined(PT_TEXT_ADDR) \
81 || defined(PT_DATA_ADDR) \
82 || defined(PT_TEXT_END_ADDR))
83 #if defined(__mcoldfire__)
84 /* These are still undefined in 3.10 kernels. */
85 #define PT_TEXT_ADDR 49*4
86 #define PT_DATA_ADDR 50*4
87 #define PT_TEXT_END_ADDR 51*4
88 /* BFIN already defines these since at least 2.6.32 kernels. */
90 #define PT_TEXT_ADDR 220
91 #define PT_TEXT_END_ADDR 224
92 #define PT_DATA_ADDR 228
93 /* These are still undefined in 3.10 kernels. */
94 #elif defined(__TMS320C6X__)
95 #define PT_TEXT_ADDR (0x10000*4)
96 #define PT_DATA_ADDR (0x10004*4)
97 #define PT_TEXT_END_ADDR (0x10008*4)
101 #ifdef HAVE_LINUX_BTRACE
102 # include "nat/linux-btrace.h"
103 # include "btrace-common.h"
106 #ifndef HAVE_ELF32_AUXV_T
107 /* Copied from glibc's elf.h. */
110 uint32_t a_type
; /* Entry type */
113 uint32_t a_val
; /* Integer value */
114 /* We use to have pointer elements added here. We cannot do that,
115 though, since it does not work when using 32-bit definitions
116 on 64-bit platforms and vice versa. */
121 #ifndef HAVE_ELF64_AUXV_T
122 /* Copied from glibc's elf.h. */
125 uint64_t a_type
; /* Entry type */
128 uint64_t a_val
; /* Integer value */
129 /* We use to have pointer elements added here. We cannot do that,
130 though, since it does not work when using 32-bit definitions
131 on 64-bit platforms and vice versa. */
136 /* Does the current host support PTRACE_GETREGSET? */
137 int have_ptrace_getregset
= -1;
141 /* See nat/linux-nat.h. */
144 ptid_of_lwp (struct lwp_info
*lwp
)
146 return ptid_of (get_lwp_thread (lwp
));
149 /* See nat/linux-nat.h. */
152 lwp_set_arch_private_info (struct lwp_info
*lwp
,
153 struct arch_lwp_info
*info
)
155 lwp
->arch_private
= info
;
158 /* See nat/linux-nat.h. */
160 struct arch_lwp_info
*
161 lwp_arch_private_info (struct lwp_info
*lwp
)
163 return lwp
->arch_private
;
166 /* See nat/linux-nat.h. */
169 lwp_is_stopped (struct lwp_info
*lwp
)
174 /* See nat/linux-nat.h. */
176 enum target_stop_reason
177 lwp_stop_reason (struct lwp_info
*lwp
)
179 return lwp
->stop_reason
;
182 /* See nat/linux-nat.h. */
185 lwp_is_stepping (struct lwp_info
*lwp
)
187 return lwp
->stepping
;
190 /* A list of all unknown processes which receive stop signals. Some
191 other process will presumably claim each of these as forked
192 children momentarily. */
194 struct simple_pid_list
196 /* The process ID. */
199 /* The status as reported by waitpid. */
203 struct simple_pid_list
*next
;
205 struct simple_pid_list
*stopped_pids
;
207 /* Trivial list manipulation functions to keep track of a list of new
208 stopped processes. */
211 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
213 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
216 new_pid
->status
= status
;
217 new_pid
->next
= *listp
;
222 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
224 struct simple_pid_list
**p
;
226 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
227 if ((*p
)->pid
== pid
)
229 struct simple_pid_list
*next
= (*p
)->next
;
231 *statusp
= (*p
)->status
;
239 enum stopping_threads_kind
241 /* Not stopping threads presently. */
242 NOT_STOPPING_THREADS
,
244 /* Stopping threads. */
247 /* Stopping and suspending threads. */
248 STOPPING_AND_SUSPENDING_THREADS
251 /* This is set while stop_all_lwps is in effect. */
252 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
254 /* FIXME make into a target method? */
255 int using_threads
= 1;
257 /* True if we're presently stabilizing threads (moving them out of
259 static int stabilizing_threads
;
261 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
262 int step
, int signal
, siginfo_t
*info
);
263 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
264 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
265 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
266 static void unsuspend_all_lwps (struct lwp_info
*except
);
267 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
268 int *wstat
, int options
);
269 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
270 static struct lwp_info
*add_lwp (ptid_t ptid
);
271 static void linux_mourn (struct process_info
*process
);
272 static int linux_stopped_by_watchpoint (void);
273 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
274 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
275 static void proceed_all_lwps (void);
276 static int finish_step_over (struct lwp_info
*lwp
);
277 static int kill_lwp (unsigned long lwpid
, int signo
);
278 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
279 static void complete_ongoing_step_over (void);
280 static int linux_low_ptrace_options (int attached
);
281 static int check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
);
282 static void proceed_one_lwp (thread_info
*thread
, lwp_info
*except
);
284 /* When the event-loop is doing a step-over, this points at the thread
286 ptid_t step_over_bkpt
;
288 /* True if the low target can hardware single-step. */
291 can_hardware_single_step (void)
293 if (the_low_target
.supports_hardware_single_step
!= NULL
)
294 return the_low_target
.supports_hardware_single_step ();
299 /* True if the low target can software single-step. Such targets
300 implement the GET_NEXT_PCS callback. */
303 can_software_single_step (void)
305 return (the_low_target
.get_next_pcs
!= NULL
);
308 /* True if the low target supports memory breakpoints. If so, we'll
309 have a GET_PC implementation. */
312 supports_breakpoints (void)
314 return (the_low_target
.get_pc
!= NULL
);
317 /* Returns true if this target can support fast tracepoints. This
318 does not mean that the in-process agent has been loaded in the
322 supports_fast_tracepoints (void)
324 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
327 /* True if LWP is stopped in its stepping range. */
330 lwp_in_step_range (struct lwp_info
*lwp
)
332 CORE_ADDR pc
= lwp
->stop_pc
;
334 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
337 struct pending_signals
341 struct pending_signals
*prev
;
344 /* The read/write ends of the pipe registered as waitable file in the
346 static int linux_event_pipe
[2] = { -1, -1 };
348 /* True if we're currently in async mode. */
349 #define target_is_async_p() (linux_event_pipe[0] != -1)
351 static void send_sigstop (struct lwp_info
*lwp
);
352 static void wait_for_sigstop (void);
354 /* Return non-zero if HEADER is a 64-bit ELF file. */
357 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
359 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
360 && header
->e_ident
[EI_MAG1
] == ELFMAG1
361 && header
->e_ident
[EI_MAG2
] == ELFMAG2
362 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
364 *machine
= header
->e_machine
;
365 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
372 /* Return non-zero if FILE is a 64-bit ELF file,
373 zero if the file is not a 64-bit ELF file,
374 and -1 if the file is not accessible or doesn't exist. */
377 elf_64_file_p (const char *file
, unsigned int *machine
)
382 fd
= open (file
, O_RDONLY
);
386 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
393 return elf_64_header_p (&header
, machine
);
396 /* Accepts an integer PID; Returns true if the executable PID is
397 running is a 64-bit ELF file.. */
400 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
404 sprintf (file
, "/proc/%d/exe", pid
);
405 return elf_64_file_p (file
, machine
);
409 delete_lwp (struct lwp_info
*lwp
)
411 struct thread_info
*thr
= get_lwp_thread (lwp
);
414 debug_printf ("deleting %ld\n", lwpid_of (thr
));
418 if (the_low_target
.delete_thread
!= NULL
)
419 the_low_target
.delete_thread (lwp
->arch_private
);
421 gdb_assert (lwp
->arch_private
== NULL
);
426 /* Add a process to the common process list, and set its private
429 static struct process_info
*
430 linux_add_process (int pid
, int attached
)
432 struct process_info
*proc
;
434 proc
= add_process (pid
, attached
);
435 proc
->priv
= XCNEW (struct process_info_private
);
437 if (the_low_target
.new_process
!= NULL
)
438 proc
->priv
->arch_private
= the_low_target
.new_process ();
443 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
445 /* Call the target arch_setup function on the current thread. */
448 linux_arch_setup (void)
450 the_low_target
.arch_setup ();
453 /* Call the target arch_setup function on THREAD. */
456 linux_arch_setup_thread (struct thread_info
*thread
)
458 struct thread_info
*saved_thread
;
460 saved_thread
= current_thread
;
461 current_thread
= thread
;
465 current_thread
= saved_thread
;
468 /* Handle a GNU/Linux extended wait response. If we see a clone,
469 fork, or vfork event, we need to add the new LWP to our list
470 (and return 0 so as not to report the trap to higher layers).
471 If we see an exec event, we will modify ORIG_EVENT_LWP to point
472 to a new LWP representing the new program. */
475 handle_extended_wait (struct lwp_info
**orig_event_lwp
, int wstat
)
477 struct lwp_info
*event_lwp
= *orig_event_lwp
;
478 int event
= linux_ptrace_get_extended_event (wstat
);
479 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
480 struct lwp_info
*new_lwp
;
482 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
484 /* All extended events we currently use are mid-syscall. Only
485 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
486 you have to be using PTRACE_SEIZE to get that. */
487 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
489 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
490 || (event
== PTRACE_EVENT_CLONE
))
493 unsigned long new_pid
;
496 /* Get the pid of the new lwp. */
497 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
500 /* If we haven't already seen the new PID stop, wait for it now. */
501 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
503 /* The new child has a pending SIGSTOP. We can't affect it until it
504 hits the SIGSTOP, but we're already attached. */
506 ret
= my_waitpid (new_pid
, &status
, __WALL
);
509 perror_with_name ("waiting for new child");
510 else if (ret
!= new_pid
)
511 warning ("wait returned unexpected PID %d", ret
);
512 else if (!WIFSTOPPED (status
))
513 warning ("wait returned unexpected status 0x%x", status
);
516 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
518 struct process_info
*parent_proc
;
519 struct process_info
*child_proc
;
520 struct lwp_info
*child_lwp
;
521 struct thread_info
*child_thr
;
522 struct target_desc
*tdesc
;
524 ptid
= ptid_build (new_pid
, new_pid
, 0);
528 debug_printf ("HEW: Got fork event from LWP %ld, "
530 ptid_get_lwp (ptid_of (event_thr
)),
531 ptid_get_pid (ptid
));
534 /* Add the new process to the tables and clone the breakpoint
535 lists of the parent. We need to do this even if the new process
536 will be detached, since we will need the process object and the
537 breakpoints to remove any breakpoints from memory when we
538 detach, and the client side will access registers. */
539 child_proc
= linux_add_process (new_pid
, 0);
540 gdb_assert (child_proc
!= NULL
);
541 child_lwp
= add_lwp (ptid
);
542 gdb_assert (child_lwp
!= NULL
);
543 child_lwp
->stopped
= 1;
544 child_lwp
->must_set_ptrace_flags
= 1;
545 child_lwp
->status_pending_p
= 0;
546 child_thr
= get_lwp_thread (child_lwp
);
547 child_thr
->last_resume_kind
= resume_stop
;
548 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
550 /* If we're suspending all threads, leave this one suspended
551 too. If the fork/clone parent is stepping over a breakpoint,
552 all other threads have been suspended already. Leave the
553 child suspended too. */
554 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
555 || event_lwp
->bp_reinsert
!= 0)
558 debug_printf ("HEW: leaving child suspended\n");
559 child_lwp
->suspended
= 1;
562 parent_proc
= get_thread_process (event_thr
);
563 child_proc
->attached
= parent_proc
->attached
;
565 if (event_lwp
->bp_reinsert
!= 0
566 && can_software_single_step ()
567 && event
== PTRACE_EVENT_VFORK
)
569 /* If we leave single-step breakpoints there, child will
570 hit it, so uninsert single-step breakpoints from parent
571 (and child). Once vfork child is done, reinsert
572 them back to parent. */
573 uninsert_single_step_breakpoints (event_thr
);
576 clone_all_breakpoints (child_thr
, event_thr
);
578 tdesc
= allocate_target_description ();
579 copy_target_description (tdesc
, parent_proc
->tdesc
);
580 child_proc
->tdesc
= tdesc
;
582 /* Clone arch-specific process data. */
583 if (the_low_target
.new_fork
!= NULL
)
584 the_low_target
.new_fork (parent_proc
, child_proc
);
586 /* Save fork info in the parent thread. */
587 if (event
== PTRACE_EVENT_FORK
)
588 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
589 else if (event
== PTRACE_EVENT_VFORK
)
590 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
592 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
594 /* The status_pending field contains bits denoting the
595 extended event, so when the pending event is handled,
596 the handler will look at lwp->waitstatus. */
597 event_lwp
->status_pending_p
= 1;
598 event_lwp
->status_pending
= wstat
;
600 /* Link the threads until the parent event is passed on to
602 event_lwp
->fork_relative
= child_lwp
;
603 child_lwp
->fork_relative
= event_lwp
;
605 /* If the parent thread is doing step-over with single-step
606 breakpoints, the list of single-step breakpoints are cloned
607 from the parent's. Remove them from the child process.
608 In case of vfork, we'll reinsert them back once vforked
610 if (event_lwp
->bp_reinsert
!= 0
611 && can_software_single_step ())
613 /* The child process is forked and stopped, so it is safe
614 to access its memory without stopping all other threads
615 from other processes. */
616 delete_single_step_breakpoints (child_thr
);
618 gdb_assert (has_single_step_breakpoints (event_thr
));
619 gdb_assert (!has_single_step_breakpoints (child_thr
));
622 /* Report the event. */
627 debug_printf ("HEW: Got clone event "
628 "from LWP %ld, new child is LWP %ld\n",
629 lwpid_of (event_thr
), new_pid
);
631 ptid
= ptid_build (pid_of (event_thr
), new_pid
, 0);
632 new_lwp
= add_lwp (ptid
);
634 /* Either we're going to immediately resume the new thread
635 or leave it stopped. linux_resume_one_lwp is a nop if it
636 thinks the thread is currently running, so set this first
637 before calling linux_resume_one_lwp. */
638 new_lwp
->stopped
= 1;
640 /* If we're suspending all threads, leave this one suspended
641 too. If the fork/clone parent is stepping over a breakpoint,
642 all other threads have been suspended already. Leave the
643 child suspended too. */
644 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
645 || event_lwp
->bp_reinsert
!= 0)
646 new_lwp
->suspended
= 1;
648 /* Normally we will get the pending SIGSTOP. But in some cases
649 we might get another signal delivered to the group first.
650 If we do get another signal, be sure not to lose it. */
651 if (WSTOPSIG (status
) != SIGSTOP
)
653 new_lwp
->stop_expected
= 1;
654 new_lwp
->status_pending_p
= 1;
655 new_lwp
->status_pending
= status
;
657 else if (report_thread_events
)
659 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
660 new_lwp
->status_pending_p
= 1;
661 new_lwp
->status_pending
= status
;
664 thread_db_notice_clone (event_thr
, ptid
);
666 /* Don't report the event. */
669 else if (event
== PTRACE_EVENT_VFORK_DONE
)
671 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
673 if (event_lwp
->bp_reinsert
!= 0 && can_software_single_step ())
675 reinsert_single_step_breakpoints (event_thr
);
677 gdb_assert (has_single_step_breakpoints (event_thr
));
680 /* Report the event. */
683 else if (event
== PTRACE_EVENT_EXEC
&& report_exec_events
)
685 struct process_info
*proc
;
686 std::vector
<int> syscalls_to_catch
;
692 debug_printf ("HEW: Got exec event from LWP %ld\n",
693 lwpid_of (event_thr
));
696 /* Get the event ptid. */
697 event_ptid
= ptid_of (event_thr
);
698 event_pid
= ptid_get_pid (event_ptid
);
700 /* Save the syscall list from the execing process. */
701 proc
= get_thread_process (event_thr
);
702 syscalls_to_catch
= std::move (proc
->syscalls_to_catch
);
704 /* Delete the execing process and all its threads. */
706 current_thread
= NULL
;
708 /* Create a new process/lwp/thread. */
709 proc
= linux_add_process (event_pid
, 0);
710 event_lwp
= add_lwp (event_ptid
);
711 event_thr
= get_lwp_thread (event_lwp
);
712 gdb_assert (current_thread
== event_thr
);
713 linux_arch_setup_thread (event_thr
);
715 /* Set the event status. */
716 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
717 event_lwp
->waitstatus
.value
.execd_pathname
718 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
720 /* Mark the exec status as pending. */
721 event_lwp
->stopped
= 1;
722 event_lwp
->status_pending_p
= 1;
723 event_lwp
->status_pending
= wstat
;
724 event_thr
->last_resume_kind
= resume_continue
;
725 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
727 /* Update syscall state in the new lwp, effectively mid-syscall too. */
728 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
730 /* Restore the list to catch. Don't rely on the client, which is free
731 to avoid sending a new list when the architecture doesn't change.
732 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
733 proc
->syscalls_to_catch
= std::move (syscalls_to_catch
);
735 /* Report the event. */
736 *orig_event_lwp
= event_lwp
;
740 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
743 /* Return the PC as read from the regcache of LWP, without any
747 get_pc (struct lwp_info
*lwp
)
749 struct thread_info
*saved_thread
;
750 struct regcache
*regcache
;
753 if (the_low_target
.get_pc
== NULL
)
756 saved_thread
= current_thread
;
757 current_thread
= get_lwp_thread (lwp
);
759 regcache
= get_thread_regcache (current_thread
, 1);
760 pc
= (*the_low_target
.get_pc
) (regcache
);
763 debug_printf ("pc is 0x%lx\n", (long) pc
);
765 current_thread
= saved_thread
;
769 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
770 Fill *SYSNO with the syscall nr trapped. */
773 get_syscall_trapinfo (struct lwp_info
*lwp
, int *sysno
)
775 struct thread_info
*saved_thread
;
776 struct regcache
*regcache
;
778 if (the_low_target
.get_syscall_trapinfo
== NULL
)
780 /* If we cannot get the syscall trapinfo, report an unknown
781 system call number. */
782 *sysno
= UNKNOWN_SYSCALL
;
786 saved_thread
= current_thread
;
787 current_thread
= get_lwp_thread (lwp
);
789 regcache
= get_thread_regcache (current_thread
, 1);
790 (*the_low_target
.get_syscall_trapinfo
) (regcache
, sysno
);
793 debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno
);
795 current_thread
= saved_thread
;
798 static int check_stopped_by_watchpoint (struct lwp_info
*child
);
800 /* Called when the LWP stopped for a signal/trap. If it stopped for a
801 trap check what caused it (breakpoint, watchpoint, trace, etc.),
802 and save the result in the LWP's stop_reason field. If it stopped
803 for a breakpoint, decrement the PC if necessary on the lwp's
804 architecture. Returns true if we now have the LWP's stop PC. */
807 save_stop_reason (struct lwp_info
*lwp
)
810 CORE_ADDR sw_breakpoint_pc
;
811 struct thread_info
*saved_thread
;
812 #if USE_SIGTRAP_SIGINFO
816 if (the_low_target
.get_pc
== NULL
)
820 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
822 /* breakpoint_at reads from the current thread. */
823 saved_thread
= current_thread
;
824 current_thread
= get_lwp_thread (lwp
);
826 #if USE_SIGTRAP_SIGINFO
827 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
828 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
830 if (siginfo
.si_signo
== SIGTRAP
)
832 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
833 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
835 /* The si_code is ambiguous on this arch -- check debug
837 if (!check_stopped_by_watchpoint (lwp
))
838 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
840 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
842 /* If we determine the LWP stopped for a SW breakpoint,
843 trust it. Particularly don't check watchpoint
844 registers, because at least on s390, we'd find
845 stopped-by-watchpoint as long as there's a watchpoint
847 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
849 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
851 /* This can indicate either a hardware breakpoint or
852 hardware watchpoint. Check debug registers. */
853 if (!check_stopped_by_watchpoint (lwp
))
854 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
856 else if (siginfo
.si_code
== TRAP_TRACE
)
858 /* We may have single stepped an instruction that
859 triggered a watchpoint. In that case, on some
860 architectures (such as x86), instead of TRAP_HWBKPT,
861 si_code indicates TRAP_TRACE, and we need to check
862 the debug registers separately. */
863 if (!check_stopped_by_watchpoint (lwp
))
864 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
869 /* We may have just stepped a breakpoint instruction. E.g., in
870 non-stop mode, GDB first tells the thread A to step a range, and
871 then the user inserts a breakpoint inside the range. In that
872 case we need to report the breakpoint PC. */
873 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
874 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
875 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
877 if (hardware_breakpoint_inserted_here (pc
))
878 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
880 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
881 check_stopped_by_watchpoint (lwp
);
884 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
888 struct thread_info
*thr
= get_lwp_thread (lwp
);
890 debug_printf ("CSBB: %s stopped by software breakpoint\n",
891 target_pid_to_str (ptid_of (thr
)));
894 /* Back up the PC if necessary. */
895 if (pc
!= sw_breakpoint_pc
)
897 struct regcache
*regcache
898 = get_thread_regcache (current_thread
, 1);
899 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
902 /* Update this so we record the correct stop PC below. */
903 pc
= sw_breakpoint_pc
;
905 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
909 struct thread_info
*thr
= get_lwp_thread (lwp
);
911 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
912 target_pid_to_str (ptid_of (thr
)));
915 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
919 struct thread_info
*thr
= get_lwp_thread (lwp
);
921 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
922 target_pid_to_str (ptid_of (thr
)));
925 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
929 struct thread_info
*thr
= get_lwp_thread (lwp
);
931 debug_printf ("CSBB: %s stopped by trace\n",
932 target_pid_to_str (ptid_of (thr
)));
937 current_thread
= saved_thread
;
941 static struct lwp_info
*
942 add_lwp (ptid_t ptid
)
944 struct lwp_info
*lwp
;
946 lwp
= XCNEW (struct lwp_info
);
948 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
950 if (the_low_target
.new_thread
!= NULL
)
951 the_low_target
.new_thread (lwp
);
953 lwp
->thread
= add_thread (ptid
, lwp
);
958 /* Callback to be used when calling fork_inferior, responsible for
959 actually initiating the tracing of the inferior. */
964 if (ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0,
965 (PTRACE_TYPE_ARG4
) 0) < 0)
966 trace_start_error_with_name ("ptrace");
968 if (setpgid (0, 0) < 0)
969 trace_start_error_with_name ("setpgid");
971 /* If GDBserver is connected to gdb via stdio, redirect the inferior's
972 stdout to stderr so that inferior i/o doesn't corrupt the connection.
973 Also, redirect stdin to /dev/null. */
974 if (remote_connection_is_stdio ())
977 trace_start_error_with_name ("close");
978 if (open ("/dev/null", O_RDONLY
) < 0)
979 trace_start_error_with_name ("open");
981 trace_start_error_with_name ("dup2");
982 if (write (2, "stdin/stdout redirected\n",
983 sizeof ("stdin/stdout redirected\n") - 1) < 0)
985 /* Errors ignored. */;
990 /* Start an inferior process and returns its pid.
991 PROGRAM is the name of the program to be started, and PROGRAM_ARGS
992 are its arguments. */
995 linux_create_inferior (const char *program
,
996 const std::vector
<char *> &program_args
)
998 struct lwp_info
*new_lwp
;
1003 maybe_disable_address_space_randomization restore_personality
1004 (disable_randomization
);
1005 std::string str_program_args
= stringify_argv (program_args
);
1007 pid
= fork_inferior (program
,
1008 str_program_args
.c_str (),
1009 get_environ ()->envp (), linux_ptrace_fun
,
1010 NULL
, NULL
, NULL
, NULL
);
1013 linux_add_process (pid
, 0);
1015 ptid
= ptid_build (pid
, pid
, 0);
1016 new_lwp
= add_lwp (ptid
);
1017 new_lwp
->must_set_ptrace_flags
= 1;
1019 post_fork_inferior (pid
, program
);
1024 /* Implement the post_create_inferior target_ops method. */
1027 linux_post_create_inferior (void)
1029 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
1031 linux_arch_setup ();
1033 if (lwp
->must_set_ptrace_flags
)
1035 struct process_info
*proc
= current_process ();
1036 int options
= linux_low_ptrace_options (proc
->attached
);
1038 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
1039 lwp
->must_set_ptrace_flags
= 0;
1043 /* Attach to an inferior process. Returns 0 on success, ERRNO on
1047 linux_attach_lwp (ptid_t ptid
)
1049 struct lwp_info
*new_lwp
;
1050 int lwpid
= ptid_get_lwp (ptid
);
1052 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
1056 new_lwp
= add_lwp (ptid
);
1058 /* We need to wait for SIGSTOP before being able to make the next
1059 ptrace call on this LWP. */
1060 new_lwp
->must_set_ptrace_flags
= 1;
1062 if (linux_proc_pid_is_stopped (lwpid
))
1065 debug_printf ("Attached to a stopped process\n");
1067 /* The process is definitely stopped. It is in a job control
1068 stop, unless the kernel predates the TASK_STOPPED /
1069 TASK_TRACED distinction, in which case it might be in a
1070 ptrace stop. Make sure it is in a ptrace stop; from there we
1071 can kill it, signal it, et cetera.
1073 First make sure there is a pending SIGSTOP. Since we are
1074 already attached, the process can not transition from stopped
1075 to running without a PTRACE_CONT; so we know this signal will
1076 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1077 probably already in the queue (unless this kernel is old
1078 enough to use TASK_STOPPED for ptrace stops); but since
1079 SIGSTOP is not an RT signal, it can only be queued once. */
1080 kill_lwp (lwpid
, SIGSTOP
);
1082 /* Finally, resume the stopped process. This will deliver the
1083 SIGSTOP (or a higher priority signal, just like normal
1084 PTRACE_ATTACH), which we'll catch later on. */
1085 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1088 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1089 brings it to a halt.
1091 There are several cases to consider here:
1093 1) gdbserver has already attached to the process and is being notified
1094 of a new thread that is being created.
1095 In this case we should ignore that SIGSTOP and resume the
1096 process. This is handled below by setting stop_expected = 1,
1097 and the fact that add_thread sets last_resume_kind ==
1100 2) This is the first thread (the process thread), and we're attaching
1101 to it via attach_inferior.
1102 In this case we want the process thread to stop.
1103 This is handled by having linux_attach set last_resume_kind ==
1104 resume_stop after we return.
1106 If the pid we are attaching to is also the tgid, we attach to and
1107 stop all the existing threads. Otherwise, we attach to pid and
1108 ignore any other threads in the same group as this pid.
1110 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1112 In this case we want the thread to stop.
1113 FIXME: This case is currently not properly handled.
1114 We should wait for the SIGSTOP but don't. Things work apparently
1115 because enough time passes between when we ptrace (ATTACH) and when
1116 gdb makes the next ptrace call on the thread.
1118 On the other hand, if we are currently trying to stop all threads, we
1119 should treat the new thread as if we had sent it a SIGSTOP. This works
1120 because we are guaranteed that the add_lwp call above added us to the
1121 end of the list, and so the new thread has not yet reached
1122 wait_for_sigstop (but will). */
1123 new_lwp
->stop_expected
= 1;
1128 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1129 already attached. Returns true if a new LWP is found, false
1133 attach_proc_task_lwp_callback (ptid_t ptid
)
1135 /* Is this a new thread? */
1136 if (find_thread_ptid (ptid
) == NULL
)
1138 int lwpid
= ptid_get_lwp (ptid
);
1142 debug_printf ("Found new lwp %d\n", lwpid
);
1144 err
= linux_attach_lwp (ptid
);
1146 /* Be quiet if we simply raced with the thread exiting. EPERM
1147 is returned if the thread's task still exists, and is marked
1148 as exited or zombie, as well as other conditions, so in that
1149 case, confirm the status in /proc/PID/status. */
1151 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1155 debug_printf ("Cannot attach to lwp %d: "
1156 "thread is gone (%d: %s)\n",
1157 lwpid
, err
, strerror (err
));
1162 warning (_("Cannot attach to lwp %d: %s"),
1164 linux_ptrace_attach_fail_reason_string (ptid
, err
));
1172 static void async_file_mark (void);
1174 /* Attach to PID. If PID is the tgid, attach to it and all
1178 linux_attach (unsigned long pid
)
1180 struct process_info
*proc
;
1181 struct thread_info
*initial_thread
;
1182 ptid_t ptid
= ptid_build (pid
, pid
, 0);
1185 /* Attach to PID. We will check for other threads
1187 err
= linux_attach_lwp (ptid
);
1189 error ("Cannot attach to process %ld: %s",
1190 pid
, linux_ptrace_attach_fail_reason_string (ptid
, err
));
1192 proc
= linux_add_process (pid
, 1);
1194 /* Don't ignore the initial SIGSTOP if we just attached to this
1195 process. It will be collected by wait shortly. */
1196 initial_thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
1197 initial_thread
->last_resume_kind
= resume_stop
;
1199 /* We must attach to every LWP. If /proc is mounted, use that to
1200 find them now. On the one hand, the inferior may be using raw
1201 clone instead of using pthreads. On the other hand, even if it
1202 is using pthreads, GDB may not be connected yet (thread_db needs
1203 to do symbol lookups, through qSymbol). Also, thread_db walks
1204 structures in the inferior's address space to find the list of
1205 threads/LWPs, and those structures may well be corrupted. Note
1206 that once thread_db is loaded, we'll still use it to list threads
1207 and associate pthread info with each LWP. */
1208 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1210 /* GDB will shortly read the xml target description for this
1211 process, to figure out the process' architecture. But the target
1212 description is only filled in when the first process/thread in
1213 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1214 that now, otherwise, if GDB is fast enough, it could read the
1215 target description _before_ that initial stop. */
1218 struct lwp_info
*lwp
;
1220 ptid_t pid_ptid
= pid_to_ptid (pid
);
1222 lwpid
= linux_wait_for_event_filtered (pid_ptid
, pid_ptid
,
1224 gdb_assert (lwpid
> 0);
1226 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
1228 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1230 lwp
->status_pending_p
= 1;
1231 lwp
->status_pending
= wstat
;
1234 initial_thread
->last_resume_kind
= resume_continue
;
1238 gdb_assert (proc
->tdesc
!= NULL
);
1245 last_thread_of_process_p (int pid
)
1247 bool seen_one
= false;
1249 thread_info
*thread
= find_thread (pid
, [&] (thread_info
*thread
)
1253 /* This is the first thread of this process we see. */
1259 /* This is the second thread of this process we see. */
1264 return thread
== NULL
;
1270 linux_kill_one_lwp (struct lwp_info
*lwp
)
1272 struct thread_info
*thr
= get_lwp_thread (lwp
);
1273 int pid
= lwpid_of (thr
);
1275 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1276 there is no signal context, and ptrace(PTRACE_KILL) (or
1277 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1278 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1279 alternative is to kill with SIGKILL. We only need one SIGKILL
1280 per process, not one for each thread. But since we still support
1281 support debugging programs using raw clone without CLONE_THREAD,
1282 we send one for each thread. For years, we used PTRACE_KILL
1283 only, so we're being a bit paranoid about some old kernels where
1284 PTRACE_KILL might work better (dubious if there are any such, but
1285 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1286 second, and so we're fine everywhere. */
1289 kill_lwp (pid
, SIGKILL
);
1292 int save_errno
= errno
;
1294 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1295 target_pid_to_str (ptid_of (thr
)),
1296 save_errno
? strerror (save_errno
) : "OK");
1300 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1303 int save_errno
= errno
;
1305 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1306 target_pid_to_str (ptid_of (thr
)),
1307 save_errno
? strerror (save_errno
) : "OK");
1311 /* Kill LWP and wait for it to die. */
1314 kill_wait_lwp (struct lwp_info
*lwp
)
1316 struct thread_info
*thr
= get_lwp_thread (lwp
);
1317 int pid
= ptid_get_pid (ptid_of (thr
));
1318 int lwpid
= ptid_get_lwp (ptid_of (thr
));
1323 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1327 linux_kill_one_lwp (lwp
);
1329 /* Make sure it died. Notes:
1331 - The loop is most likely unnecessary.
1333 - We don't use linux_wait_for_event as that could delete lwps
1334 while we're iterating over them. We're not interested in
1335 any pending status at this point, only in making sure all
1336 wait status on the kernel side are collected until the
1339 - We don't use __WALL here as the __WALL emulation relies on
1340 SIGCHLD, and killing a stopped process doesn't generate
1341 one, nor an exit status.
1343 res
= my_waitpid (lwpid
, &wstat
, 0);
1344 if (res
== -1 && errno
== ECHILD
)
1345 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1346 } while (res
> 0 && WIFSTOPPED (wstat
));
1348 /* Even if it was stopped, the child may have already disappeared.
1349 E.g., if it was killed by SIGKILL. */
1350 if (res
< 0 && errno
!= ECHILD
)
1351 perror_with_name ("kill_wait_lwp");
1354 /* Callback for `for_each_thread'. Kills an lwp of a given process,
1355 except the leader. */
1358 kill_one_lwp_callback (thread_info
*thread
, int pid
)
1360 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1362 /* We avoid killing the first thread here, because of a Linux kernel (at
1363 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1364 the children get a chance to be reaped, it will remain a zombie
1367 if (lwpid_of (thread
) == pid
)
1370 debug_printf ("lkop: is last of process %s\n",
1371 target_pid_to_str (thread
->id
));
1375 kill_wait_lwp (lwp
);
1379 linux_kill (int pid
)
1381 struct process_info
*process
;
1382 struct lwp_info
*lwp
;
1384 process
= find_process_pid (pid
);
1385 if (process
== NULL
)
1388 /* If we're killing a running inferior, make sure it is stopped
1389 first, as PTRACE_KILL will not work otherwise. */
1390 stop_all_lwps (0, NULL
);
1392 for_each_thread (pid
, [&] (thread_info
*thread
)
1394 kill_one_lwp_callback (thread
, pid
);
1397 /* See the comment in linux_kill_one_lwp. We did not kill the first
1398 thread in the list, so do so now. */
1399 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1404 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1408 kill_wait_lwp (lwp
);
1410 the_target
->mourn (process
);
1412 /* Since we presently can only stop all lwps of all processes, we
1413 need to unstop lwps of other processes. */
1414 unstop_all_lwps (0, NULL
);
1418 /* Get pending signal of THREAD, for detaching purposes. This is the
1419 signal the thread last stopped for, which we need to deliver to the
1420 thread when detaching, otherwise, it'd be suppressed/lost. */
1423 get_detach_signal (struct thread_info
*thread
)
1425 enum gdb_signal signo
= GDB_SIGNAL_0
;
1427 struct lwp_info
*lp
= get_thread_lwp (thread
);
1429 if (lp
->status_pending_p
)
1430 status
= lp
->status_pending
;
1433 /* If the thread had been suspended by gdbserver, and it stopped
1434 cleanly, then it'll have stopped with SIGSTOP. But we don't
1435 want to deliver that SIGSTOP. */
1436 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1437 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1440 /* Otherwise, we may need to deliver the signal we
1442 status
= lp
->last_status
;
1445 if (!WIFSTOPPED (status
))
1448 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1449 target_pid_to_str (ptid_of (thread
)));
1453 /* Extended wait statuses aren't real SIGTRAPs. */
1454 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1457 debug_printf ("GPS: lwp %s had stopped with extended "
1458 "status: no pending signal\n",
1459 target_pid_to_str (ptid_of (thread
)));
1463 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1465 if (program_signals_p
&& !program_signals
[signo
])
1468 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1469 target_pid_to_str (ptid_of (thread
)),
1470 gdb_signal_to_string (signo
));
1473 else if (!program_signals_p
1474 /* If we have no way to know which signals GDB does not
1475 want to have passed to the program, assume
1476 SIGTRAP/SIGINT, which is GDB's default. */
1477 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1480 debug_printf ("GPS: lwp %s had signal %s, "
1481 "but we don't know if we should pass it. "
1482 "Default to not.\n",
1483 target_pid_to_str (ptid_of (thread
)),
1484 gdb_signal_to_string (signo
));
1490 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1491 target_pid_to_str (ptid_of (thread
)),
1492 gdb_signal_to_string (signo
));
1494 return WSTOPSIG (status
);
1498 /* Detach from LWP. */
1501 linux_detach_one_lwp (struct lwp_info
*lwp
)
1503 struct thread_info
*thread
= get_lwp_thread (lwp
);
1507 /* If there is a pending SIGSTOP, get rid of it. */
1508 if (lwp
->stop_expected
)
1511 debug_printf ("Sending SIGCONT to %s\n",
1512 target_pid_to_str (ptid_of (thread
)));
1514 kill_lwp (lwpid_of (thread
), SIGCONT
);
1515 lwp
->stop_expected
= 0;
1518 /* Pass on any pending signal for this thread. */
1519 sig
= get_detach_signal (thread
);
1521 /* Preparing to resume may try to write registers, and fail if the
1522 lwp is zombie. If that happens, ignore the error. We'll handle
1523 it below, when detach fails with ESRCH. */
1526 /* Flush any pending changes to the process's registers. */
1527 regcache_invalidate_thread (thread
);
1529 /* Finally, let it resume. */
1530 if (the_low_target
.prepare_to_resume
!= NULL
)
1531 the_low_target
.prepare_to_resume (lwp
);
1533 CATCH (ex
, RETURN_MASK_ERROR
)
1535 if (!check_ptrace_stopped_lwp_gone (lwp
))
1536 throw_exception (ex
);
1540 lwpid
= lwpid_of (thread
);
1541 if (ptrace (PTRACE_DETACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0,
1542 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1544 int save_errno
= errno
;
1546 /* We know the thread exists, so ESRCH must mean the lwp is
1547 zombie. This can happen if one of the already-detached
1548 threads exits the whole thread group. In that case we're
1549 still attached, and must reap the lwp. */
1550 if (save_errno
== ESRCH
)
1554 ret
= my_waitpid (lwpid
, &status
, __WALL
);
1557 warning (_("Couldn't reap LWP %d while detaching: %s"),
1558 lwpid
, strerror (errno
));
1560 else if (!WIFEXITED (status
) && !WIFSIGNALED (status
))
1562 warning (_("Reaping LWP %d while detaching "
1563 "returned unexpected status 0x%x"),
1569 error (_("Can't detach %s: %s"),
1570 target_pid_to_str (ptid_of (thread
)),
1571 strerror (save_errno
));
1574 else if (debug_threads
)
1576 debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
1577 target_pid_to_str (ptid_of (thread
)),
1584 /* Callback for for_each_thread. Detaches from non-leader threads of a
1588 linux_detach_lwp_callback (thread_info
*thread
)
1590 /* We don't actually detach from the thread group leader just yet.
1591 If the thread group exits, we must reap the zombie clone lwps
1592 before we're able to reap the leader. */
1593 if (thread
->id
.pid () == thread
->id
.lwp ())
1596 lwp_info
*lwp
= get_thread_lwp (thread
);
1597 linux_detach_one_lwp (lwp
);
1601 linux_detach (int pid
)
1603 struct process_info
*process
;
1604 struct lwp_info
*main_lwp
;
1606 process
= find_process_pid (pid
);
1607 if (process
== NULL
)
1610 /* As there's a step over already in progress, let it finish first,
1611 otherwise nesting a stabilize_threads operation on top gets real
1613 complete_ongoing_step_over ();
1615 /* Stop all threads before detaching. First, ptrace requires that
1616 the thread is stopped to sucessfully detach. Second, thread_db
1617 may need to uninstall thread event breakpoints from memory, which
1618 only works with a stopped process anyway. */
1619 stop_all_lwps (0, NULL
);
1621 #ifdef USE_THREAD_DB
1622 thread_db_detach (process
);
1625 /* Stabilize threads (move out of jump pads). */
1626 stabilize_threads ();
1628 /* Detach from the clone lwps first. If the thread group exits just
1629 while we're detaching, we must reap the clone lwps before we're
1630 able to reap the leader. */
1631 for_each_thread (pid
, linux_detach_lwp_callback
);
1633 main_lwp
= find_lwp_pid (pid_to_ptid (pid
));
1634 linux_detach_one_lwp (main_lwp
);
1636 the_target
->mourn (process
);
1638 /* Since we presently can only stop all lwps of all processes, we
1639 need to unstop lwps of other processes. */
1640 unstop_all_lwps (0, NULL
);
1644 /* Remove all LWPs that belong to process PROC from the lwp list. */
1647 linux_mourn (struct process_info
*process
)
1649 struct process_info_private
*priv
;
1651 #ifdef USE_THREAD_DB
1652 thread_db_mourn (process
);
1655 for_each_thread (process
->pid
, [] (thread_info
*thread
)
1657 delete_lwp (get_thread_lwp (thread
));
1660 /* Freeing all private data. */
1661 priv
= process
->priv
;
1662 if (the_low_target
.delete_process
!= NULL
)
1663 the_low_target
.delete_process (priv
->arch_private
);
1665 gdb_assert (priv
->arch_private
== NULL
);
1667 process
->priv
= NULL
;
1669 remove_process (process
);
1673 linux_join (int pid
)
1678 ret
= my_waitpid (pid
, &status
, 0);
1679 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1681 } while (ret
!= -1 || errno
!= ECHILD
);
1684 /* Return nonzero if the given thread is still alive. */
1686 linux_thread_alive (ptid_t ptid
)
1688 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1690 /* We assume we always know if a thread exits. If a whole process
1691 exited but we still haven't been able to report it to GDB, we'll
1692 hold on to the last lwp of the dead process. */
1694 return !lwp_is_marked_dead (lwp
);
1699 /* Return 1 if this lwp still has an interesting status pending. If
1700 not (e.g., it had stopped for a breakpoint that is gone), return
1704 thread_still_has_status_pending_p (struct thread_info
*thread
)
1706 struct lwp_info
*lp
= get_thread_lwp (thread
);
1708 if (!lp
->status_pending_p
)
1711 if (thread
->last_resume_kind
!= resume_stop
1712 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1713 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1715 struct thread_info
*saved_thread
;
1719 gdb_assert (lp
->last_status
!= 0);
1723 saved_thread
= current_thread
;
1724 current_thread
= thread
;
1726 if (pc
!= lp
->stop_pc
)
1729 debug_printf ("PC of %ld changed\n",
1734 #if !USE_SIGTRAP_SIGINFO
1735 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1736 && !(*the_low_target
.breakpoint_at
) (pc
))
1739 debug_printf ("previous SW breakpoint of %ld gone\n",
1743 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1744 && !hardware_breakpoint_inserted_here (pc
))
1747 debug_printf ("previous HW breakpoint of %ld gone\n",
1753 current_thread
= saved_thread
;
1758 debug_printf ("discarding pending breakpoint status\n");
1759 lp
->status_pending_p
= 0;
1767 /* Returns true if LWP is resumed from the client's perspective. */
1770 lwp_resumed (struct lwp_info
*lwp
)
1772 struct thread_info
*thread
= get_lwp_thread (lwp
);
1774 if (thread
->last_resume_kind
!= resume_stop
)
1777 /* Did gdb send us a `vCont;t', but we haven't reported the
1778 corresponding stop to gdb yet? If so, the thread is still
1779 resumed/running from gdb's perspective. */
1780 if (thread
->last_resume_kind
== resume_stop
1781 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1787 /* Return true if this lwp has an interesting status pending. */
1789 status_pending_p_callback (thread_info
*thread
, ptid_t ptid
)
1791 struct lwp_info
*lp
= get_thread_lwp (thread
);
1793 /* Check if we're only interested in events from a specific process
1794 or a specific LWP. */
1795 if (!thread
->id
.matches (ptid
))
1798 if (!lwp_resumed (lp
))
1801 if (lp
->status_pending_p
1802 && !thread_still_has_status_pending_p (thread
))
1804 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1808 return lp
->status_pending_p
;
1812 find_lwp_pid (ptid_t ptid
)
1814 thread_info
*thread
= find_thread ([&] (thread_info
*thread
)
1816 int lwp
= ptid
.lwp () != 0 ? ptid
.lwp () : ptid
.pid ();
1817 return thread
->id
.lwp () == lwp
;
1823 return get_thread_lwp (thread
);
1826 /* Return the number of known LWPs in the tgid given by PID. */
1833 for_each_thread (pid
, [&] (thread_info
*thread
)
1841 /* See nat/linux-nat.h. */
1844 iterate_over_lwps (ptid_t filter
,
1845 iterate_over_lwps_ftype callback
,
1848 thread_info
*thread
= find_thread (filter
, [&] (thread_info
*thread
)
1850 lwp_info
*lwp
= get_thread_lwp (thread
);
1852 return callback (lwp
, data
);
1858 return get_thread_lwp (thread
);
1861 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1862 their exits until all other threads in the group have exited. */
1865 check_zombie_leaders (void)
1867 for_each_process ([] (process_info
*proc
) {
1868 pid_t leader_pid
= pid_of (proc
);
1869 struct lwp_info
*leader_lp
;
1871 leader_lp
= find_lwp_pid (pid_to_ptid (leader_pid
));
1874 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1875 "num_lwps=%d, zombie=%d\n",
1876 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1877 linux_proc_pid_is_zombie (leader_pid
));
1879 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1880 /* Check if there are other threads in the group, as we may
1881 have raced with the inferior simply exiting. */
1882 && !last_thread_of_process_p (leader_pid
)
1883 && linux_proc_pid_is_zombie (leader_pid
))
1885 /* A leader zombie can mean one of two things:
1887 - It exited, and there's an exit status pending
1888 available, or only the leader exited (not the whole
1889 program). In the latter case, we can't waitpid the
1890 leader's exit status until all other threads are gone.
1892 - There are 3 or more threads in the group, and a thread
1893 other than the leader exec'd. On an exec, the Linux
1894 kernel destroys all other threads (except the execing
1895 one) in the thread group, and resets the execing thread's
1896 tid to the tgid. No exit notification is sent for the
1897 execing thread -- from the ptracer's perspective, it
1898 appears as though the execing thread just vanishes.
1899 Until we reap all other threads except the leader and the
1900 execing thread, the leader will be zombie, and the
1901 execing thread will be in `D (disc sleep)'. As soon as
1902 all other threads are reaped, the execing thread changes
1903 it's tid to the tgid, and the previous (zombie) leader
1904 vanishes, giving place to the "new" leader. We could try
1905 distinguishing the exit and exec cases, by waiting once
1906 more, and seeing if something comes out, but it doesn't
1907 sound useful. The previous leader _does_ go away, and
1908 we'll re-add the new one once we see the exec event
1909 (which is just the same as what would happen if the
1910 previous leader did exit voluntarily before some other
1914 debug_printf ("CZL: Thread group leader %d zombie "
1915 "(it exited, or another thread execd).\n",
1918 delete_lwp (leader_lp
);
1923 /* Callback for `find_thread'. Returns the first LWP that is not
1927 not_stopped_callback (thread_info
*thread
, ptid_t filter
)
1929 if (!thread
->id
.matches (filter
))
1932 lwp_info
*lwp
= get_thread_lwp (thread
);
1934 return !lwp
->stopped
;
1937 /* Increment LWP's suspend count. */
1940 lwp_suspended_inc (struct lwp_info
*lwp
)
1944 if (debug_threads
&& lwp
->suspended
> 4)
1946 struct thread_info
*thread
= get_lwp_thread (lwp
);
1948 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1949 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1953 /* Decrement LWP's suspend count. */
1956 lwp_suspended_decr (struct lwp_info
*lwp
)
1960 if (lwp
->suspended
< 0)
1962 struct thread_info
*thread
= get_lwp_thread (lwp
);
1964 internal_error (__FILE__
, __LINE__
,
1965 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1970 /* This function should only be called if the LWP got a SIGTRAP.
1972 Handle any tracepoint steps or hits. Return true if a tracepoint
1973 event was handled, 0 otherwise. */
1976 handle_tracepoints (struct lwp_info
*lwp
)
1978 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1979 int tpoint_related_event
= 0;
1981 gdb_assert (lwp
->suspended
== 0);
1983 /* If this tracepoint hit causes a tracing stop, we'll immediately
1984 uninsert tracepoints. To do this, we temporarily pause all
1985 threads, unpatch away, and then unpause threads. We need to make
1986 sure the unpausing doesn't resume LWP too. */
1987 lwp_suspended_inc (lwp
);
1989 /* And we need to be sure that any all-threads-stopping doesn't try
1990 to move threads out of the jump pads, as it could deadlock the
1991 inferior (LWP could be in the jump pad, maybe even holding the
1994 /* Do any necessary step collect actions. */
1995 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1997 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1999 /* See if we just hit a tracepoint and do its main collect
2001 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
2003 lwp_suspended_decr (lwp
);
2005 gdb_assert (lwp
->suspended
== 0);
2006 gdb_assert (!stabilizing_threads
2007 || (lwp
->collecting_fast_tracepoint
2008 != fast_tpoint_collect_result::not_collecting
));
2010 if (tpoint_related_event
)
2013 debug_printf ("got a tracepoint event\n");
2020 /* Convenience wrapper. Returns information about LWP's fast tracepoint
2021 collection status. */
2023 static fast_tpoint_collect_result
2024 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
2025 struct fast_tpoint_collect_status
*status
)
2027 CORE_ADDR thread_area
;
2028 struct thread_info
*thread
= get_lwp_thread (lwp
);
2030 if (the_low_target
.get_thread_area
== NULL
)
2031 return fast_tpoint_collect_result::not_collecting
;
2033 /* Get the thread area address. This is used to recognize which
2034 thread is which when tracing with the in-process agent library.
2035 We don't read anything from the address, and treat it as opaque;
2036 it's the address itself that we assume is unique per-thread. */
2037 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
2038 return fast_tpoint_collect_result::not_collecting
;
2040 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
2043 /* The reason we resume in the caller, is because we want to be able
2044 to pass lwp->status_pending as WSTAT, and we need to clear
2045 status_pending_p before resuming, otherwise, linux_resume_one_lwp
2046 refuses to resume. */
2049 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
2051 struct thread_info
*saved_thread
;
2053 saved_thread
= current_thread
;
2054 current_thread
= get_lwp_thread (lwp
);
2057 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
2058 && supports_fast_tracepoints ()
2059 && agent_loaded_p ())
2061 struct fast_tpoint_collect_status status
;
2064 debug_printf ("Checking whether LWP %ld needs to move out of the "
2066 lwpid_of (current_thread
));
2068 fast_tpoint_collect_result r
2069 = linux_fast_tracepoint_collecting (lwp
, &status
);
2072 || (WSTOPSIG (*wstat
) != SIGILL
2073 && WSTOPSIG (*wstat
) != SIGFPE
2074 && WSTOPSIG (*wstat
) != SIGSEGV
2075 && WSTOPSIG (*wstat
) != SIGBUS
))
2077 lwp
->collecting_fast_tracepoint
= r
;
2079 if (r
!= fast_tpoint_collect_result::not_collecting
)
2081 if (r
== fast_tpoint_collect_result::before_insn
2082 && lwp
->exit_jump_pad_bkpt
== NULL
)
2084 /* Haven't executed the original instruction yet.
2085 Set breakpoint there, and wait till it's hit,
2086 then single-step until exiting the jump pad. */
2087 lwp
->exit_jump_pad_bkpt
2088 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2092 debug_printf ("Checking whether LWP %ld needs to move out of "
2093 "the jump pad...it does\n",
2094 lwpid_of (current_thread
));
2095 current_thread
= saved_thread
;
2102 /* If we get a synchronous signal while collecting, *and*
2103 while executing the (relocated) original instruction,
2104 reset the PC to point at the tpoint address, before
2105 reporting to GDB. Otherwise, it's an IPA lib bug: just
2106 report the signal to GDB, and pray for the best. */
2108 lwp
->collecting_fast_tracepoint
2109 = fast_tpoint_collect_result::not_collecting
;
2111 if (r
!= fast_tpoint_collect_result::not_collecting
2112 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2113 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2116 struct regcache
*regcache
;
2118 /* The si_addr on a few signals references the address
2119 of the faulting instruction. Adjust that as
2121 if ((WSTOPSIG (*wstat
) == SIGILL
2122 || WSTOPSIG (*wstat
) == SIGFPE
2123 || WSTOPSIG (*wstat
) == SIGBUS
2124 || WSTOPSIG (*wstat
) == SIGSEGV
)
2125 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2126 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2127 /* Final check just to make sure we don't clobber
2128 the siginfo of non-kernel-sent signals. */
2129 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2131 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2132 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2133 (PTRACE_TYPE_ARG3
) 0, &info
);
2136 regcache
= get_thread_regcache (current_thread
, 1);
2137 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
2138 lwp
->stop_pc
= status
.tpoint_addr
;
2140 /* Cancel any fast tracepoint lock this thread was
2142 force_unlock_trace_buffer ();
2145 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2148 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2149 "stopping all threads momentarily.\n");
2151 stop_all_lwps (1, lwp
);
2153 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2154 lwp
->exit_jump_pad_bkpt
= NULL
;
2156 unstop_all_lwps (1, lwp
);
2158 gdb_assert (lwp
->suspended
>= 0);
2164 debug_printf ("Checking whether LWP %ld needs to move out of the "
2166 lwpid_of (current_thread
));
2168 current_thread
= saved_thread
;
2172 /* Enqueue one signal in the "signals to report later when out of the
2176 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2178 struct pending_signals
*p_sig
;
2179 struct thread_info
*thread
= get_lwp_thread (lwp
);
2182 debug_printf ("Deferring signal %d for LWP %ld.\n",
2183 WSTOPSIG (*wstat
), lwpid_of (thread
));
2187 struct pending_signals
*sig
;
2189 for (sig
= lwp
->pending_signals_to_report
;
2192 debug_printf (" Already queued %d\n",
2195 debug_printf (" (no more currently queued signals)\n");
2198 /* Don't enqueue non-RT signals if they are already in the deferred
2199 queue. (SIGSTOP being the easiest signal to see ending up here
2201 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2203 struct pending_signals
*sig
;
2205 for (sig
= lwp
->pending_signals_to_report
;
2209 if (sig
->signal
== WSTOPSIG (*wstat
))
2212 debug_printf ("Not requeuing already queued non-RT signal %d"
2221 p_sig
= XCNEW (struct pending_signals
);
2222 p_sig
->prev
= lwp
->pending_signals_to_report
;
2223 p_sig
->signal
= WSTOPSIG (*wstat
);
2225 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2228 lwp
->pending_signals_to_report
= p_sig
;
2231 /* Dequeue one signal from the "signals to report later when out of
2232 the jump pad" list. */
2235 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2237 struct thread_info
*thread
= get_lwp_thread (lwp
);
2239 if (lwp
->pending_signals_to_report
!= NULL
)
2241 struct pending_signals
**p_sig
;
2243 p_sig
= &lwp
->pending_signals_to_report
;
2244 while ((*p_sig
)->prev
!= NULL
)
2245 p_sig
= &(*p_sig
)->prev
;
2247 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2248 if ((*p_sig
)->info
.si_signo
!= 0)
2249 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2255 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2256 WSTOPSIG (*wstat
), lwpid_of (thread
));
2260 struct pending_signals
*sig
;
2262 for (sig
= lwp
->pending_signals_to_report
;
2265 debug_printf (" Still queued %d\n",
2268 debug_printf (" (no more queued signals)\n");
2277 /* Fetch the possibly triggered data watchpoint info and store it in
2280 On some archs, like x86, that use debug registers to set
2281 watchpoints, it's possible that the way to know which watched
2282 address trapped, is to check the register that is used to select
2283 which address to watch. Problem is, between setting the watchpoint
2284 and reading back which data address trapped, the user may change
2285 the set of watchpoints, and, as a consequence, GDB changes the
2286 debug registers in the inferior. To avoid reading back a stale
2287 stopped-data-address when that happens, we cache in LP the fact
2288 that a watchpoint trapped, and the corresponding data address, as
2289 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2290 registers meanwhile, we have the cached data we can rely on. */
2293 check_stopped_by_watchpoint (struct lwp_info
*child
)
2295 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2297 struct thread_info
*saved_thread
;
2299 saved_thread
= current_thread
;
2300 current_thread
= get_lwp_thread (child
);
2302 if (the_low_target
.stopped_by_watchpoint ())
2304 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2306 if (the_low_target
.stopped_data_address
!= NULL
)
2307 child
->stopped_data_address
2308 = the_low_target
.stopped_data_address ();
2310 child
->stopped_data_address
= 0;
2313 current_thread
= saved_thread
;
2316 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2319 /* Return the ptrace options that we want to try to enable. */
2322 linux_low_ptrace_options (int attached
)
2327 options
|= PTRACE_O_EXITKILL
;
2329 if (report_fork_events
)
2330 options
|= PTRACE_O_TRACEFORK
;
2332 if (report_vfork_events
)
2333 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2335 if (report_exec_events
)
2336 options
|= PTRACE_O_TRACEEXEC
;
2338 options
|= PTRACE_O_TRACESYSGOOD
;
2343 /* Do low-level handling of the event, and check if we should go on
2344 and pass it to caller code. Return the affected lwp if we are, or
2347 static struct lwp_info
*
2348 linux_low_filter_event (int lwpid
, int wstat
)
2350 struct lwp_info
*child
;
2351 struct thread_info
*thread
;
2352 int have_stop_pc
= 0;
2354 child
= find_lwp_pid (pid_to_ptid (lwpid
));
2356 /* Check for stop events reported by a process we didn't already
2357 know about - anything not already in our LWP list.
2359 If we're expecting to receive stopped processes after
2360 fork, vfork, and clone events, then we'll just add the
2361 new one to our list and go back to waiting for the event
2362 to be reported - the stopped process might be returned
2363 from waitpid before or after the event is.
2365 But note the case of a non-leader thread exec'ing after the
2366 leader having exited, and gone from our lists (because
2367 check_zombie_leaders deleted it). The non-leader thread
2368 changes its tid to the tgid. */
2370 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2371 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2375 /* A multi-thread exec after we had seen the leader exiting. */
2378 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2379 "after exec.\n", lwpid
);
2382 child_ptid
= ptid_build (lwpid
, lwpid
, 0);
2383 child
= add_lwp (child_ptid
);
2385 current_thread
= child
->thread
;
2388 /* If we didn't find a process, one of two things presumably happened:
2389 - A process we started and then detached from has exited. Ignore it.
2390 - A process we are controlling has forked and the new child's stop
2391 was reported to us by the kernel. Save its PID. */
2392 if (child
== NULL
&& WIFSTOPPED (wstat
))
2394 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2397 else if (child
== NULL
)
2400 thread
= get_lwp_thread (child
);
2404 child
->last_status
= wstat
;
2406 /* Check if the thread has exited. */
2407 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2410 debug_printf ("LLFE: %d exited.\n", lwpid
);
2412 if (finish_step_over (child
))
2414 /* Unsuspend all other LWPs, and set them back running again. */
2415 unsuspend_all_lwps (child
);
2418 /* If there is at least one more LWP, then the exit signal was
2419 not the end of the debugged application and should be
2420 ignored, unless GDB wants to hear about thread exits. */
2421 if (report_thread_events
2422 || last_thread_of_process_p (pid_of (thread
)))
2424 /* Since events are serialized to GDB core, and we can't
2425 report this one right now. Leave the status pending for
2426 the next time we're able to report it. */
2427 mark_lwp_dead (child
, wstat
);
2437 gdb_assert (WIFSTOPPED (wstat
));
2439 if (WIFSTOPPED (wstat
))
2441 struct process_info
*proc
;
2443 /* Architecture-specific setup after inferior is running. */
2444 proc
= find_process_pid (pid_of (thread
));
2445 if (proc
->tdesc
== NULL
)
2449 /* This needs to happen after we have attached to the
2450 inferior and it is stopped for the first time, but
2451 before we access any inferior registers. */
2452 linux_arch_setup_thread (thread
);
2456 /* The process is started, but GDBserver will do
2457 architecture-specific setup after the program stops at
2458 the first instruction. */
2459 child
->status_pending_p
= 1;
2460 child
->status_pending
= wstat
;
2466 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2468 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2469 int options
= linux_low_ptrace_options (proc
->attached
);
2471 linux_enable_event_reporting (lwpid
, options
);
2472 child
->must_set_ptrace_flags
= 0;
2475 /* Always update syscall_state, even if it will be filtered later. */
2476 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2478 child
->syscall_state
2479 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2480 ? TARGET_WAITKIND_SYSCALL_RETURN
2481 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2485 /* Almost all other ptrace-stops are known to be outside of system
2486 calls, with further exceptions in handle_extended_wait. */
2487 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2490 /* Be careful to not overwrite stop_pc until save_stop_reason is
2492 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2493 && linux_is_extended_waitstatus (wstat
))
2495 child
->stop_pc
= get_pc (child
);
2496 if (handle_extended_wait (&child
, wstat
))
2498 /* The event has been handled, so just return without
2504 if (linux_wstatus_maybe_breakpoint (wstat
))
2506 if (save_stop_reason (child
))
2511 child
->stop_pc
= get_pc (child
);
2513 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2514 && child
->stop_expected
)
2517 debug_printf ("Expected stop.\n");
2518 child
->stop_expected
= 0;
2520 if (thread
->last_resume_kind
== resume_stop
)
2522 /* We want to report the stop to the core. Treat the
2523 SIGSTOP as a normal event. */
2525 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2526 target_pid_to_str (ptid_of (thread
)));
2528 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2530 /* Stopping threads. We don't want this SIGSTOP to end up
2533 debug_printf ("LLW: SIGSTOP caught for %s "
2534 "while stopping threads.\n",
2535 target_pid_to_str (ptid_of (thread
)));
2540 /* This is a delayed SIGSTOP. Filter out the event. */
2542 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2543 child
->stepping
? "step" : "continue",
2544 target_pid_to_str (ptid_of (thread
)));
2546 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2551 child
->status_pending_p
= 1;
2552 child
->status_pending
= wstat
;
2556 /* Return true if THREAD is doing hardware single step. */
2559 maybe_hw_step (struct thread_info
*thread
)
2561 if (can_hardware_single_step ())
2565 /* GDBserver must insert single-step breakpoint for software
2567 gdb_assert (has_single_step_breakpoints (thread
));
2572 /* Resume LWPs that are currently stopped without any pending status
2573 to report, but are resumed from the core's perspective. */
2576 resume_stopped_resumed_lwps (thread_info
*thread
)
2578 struct lwp_info
*lp
= get_thread_lwp (thread
);
2582 && !lp
->status_pending_p
2583 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2587 if (thread
->last_resume_kind
== resume_step
)
2588 step
= maybe_hw_step (thread
);
2591 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2592 target_pid_to_str (ptid_of (thread
)),
2593 paddress (lp
->stop_pc
),
2596 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2600 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2601 match FILTER_PTID (leaving others pending). The PTIDs can be:
2602 minus_one_ptid, to specify any child; a pid PTID, specifying all
2603 lwps of a thread group; or a PTID representing a single lwp. Store
2604 the stop status through the status pointer WSTAT. OPTIONS is
2605 passed to the waitpid call. Return 0 if no event was found and
2606 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2607 was found. Return the PID of the stopped child otherwise. */
2610 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2611 int *wstatp
, int options
)
2613 struct thread_info
*event_thread
;
2614 struct lwp_info
*event_child
, *requested_child
;
2615 sigset_t block_mask
, prev_mask
;
2618 /* N.B. event_thread points to the thread_info struct that contains
2619 event_child. Keep them in sync. */
2620 event_thread
= NULL
;
2622 requested_child
= NULL
;
2624 /* Check for a lwp with a pending status. */
2626 if (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2628 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2630 return status_pending_p_callback (thread
, filter_ptid
);
2633 if (event_thread
!= NULL
)
2634 event_child
= get_thread_lwp (event_thread
);
2635 if (debug_threads
&& event_thread
)
2636 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2638 else if (!ptid_equal (filter_ptid
, null_ptid
))
2640 requested_child
= find_lwp_pid (filter_ptid
);
2642 if (stopping_threads
== NOT_STOPPING_THREADS
2643 && requested_child
->status_pending_p
2644 && (requested_child
->collecting_fast_tracepoint
2645 != fast_tpoint_collect_result::not_collecting
))
2647 enqueue_one_deferred_signal (requested_child
,
2648 &requested_child
->status_pending
);
2649 requested_child
->status_pending_p
= 0;
2650 requested_child
->status_pending
= 0;
2651 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2654 if (requested_child
->suspended
2655 && requested_child
->status_pending_p
)
2657 internal_error (__FILE__
, __LINE__
,
2658 "requesting an event out of a"
2659 " suspended child?");
2662 if (requested_child
->status_pending_p
)
2664 event_child
= requested_child
;
2665 event_thread
= get_lwp_thread (event_child
);
2669 if (event_child
!= NULL
)
2672 debug_printf ("Got an event from pending child %ld (%04x)\n",
2673 lwpid_of (event_thread
), event_child
->status_pending
);
2674 *wstatp
= event_child
->status_pending
;
2675 event_child
->status_pending_p
= 0;
2676 event_child
->status_pending
= 0;
2677 current_thread
= event_thread
;
2678 return lwpid_of (event_thread
);
2681 /* But if we don't find a pending event, we'll have to wait.
2683 We only enter this loop if no process has a pending wait status.
2684 Thus any action taken in response to a wait status inside this
2685 loop is responding as soon as we detect the status, not after any
2688 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2689 all signals while here. */
2690 sigfillset (&block_mask
);
2691 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2693 /* Always pull all events out of the kernel. We'll randomly select
2694 an event LWP out of all that have events, to prevent
2696 while (event_child
== NULL
)
2700 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2703 - If the thread group leader exits while other threads in the
2704 thread group still exist, waitpid(TGID, ...) hangs. That
2705 waitpid won't return an exit status until the other threads
2706 in the group are reaped.
2708 - When a non-leader thread execs, that thread just vanishes
2709 without reporting an exit (so we'd hang if we waited for it
2710 explicitly in that case). The exec event is reported to
2713 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2716 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2717 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2723 debug_printf ("LLW: waitpid %ld received %s\n",
2724 (long) ret
, status_to_str (*wstatp
));
2727 /* Filter all events. IOW, leave all events pending. We'll
2728 randomly select an event LWP out of all that have events
2730 linux_low_filter_event (ret
, *wstatp
);
2731 /* Retry until nothing comes out of waitpid. A single
2732 SIGCHLD can indicate more than one child stopped. */
2736 /* Now that we've pulled all events out of the kernel, resume
2737 LWPs that don't have an interesting event to report. */
2738 if (stopping_threads
== NOT_STOPPING_THREADS
)
2739 for_each_thread (resume_stopped_resumed_lwps
);
2741 /* ... and find an LWP with a status to report to the core, if
2743 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2745 return status_pending_p_callback (thread
, filter_ptid
);
2748 if (event_thread
!= NULL
)
2750 event_child
= get_thread_lwp (event_thread
);
2751 *wstatp
= event_child
->status_pending
;
2752 event_child
->status_pending_p
= 0;
2753 event_child
->status_pending
= 0;
2757 /* Check for zombie thread group leaders. Those can't be reaped
2758 until all other threads in the thread group are. */
2759 check_zombie_leaders ();
2761 auto not_stopped
= [&] (thread_info
*thread
)
2763 return not_stopped_callback (thread
, wait_ptid
);
2766 /* If there are no resumed children left in the set of LWPs we
2767 want to wait for, bail. We can't just block in
2768 waitpid/sigsuspend, because lwps might have been left stopped
2769 in trace-stop state, and we'd be stuck forever waiting for
2770 their status to change (which would only happen if we resumed
2771 them). Even if WNOHANG is set, this return code is preferred
2772 over 0 (below), as it is more detailed. */
2773 if (find_thread (not_stopped
) == NULL
)
2776 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2777 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2781 /* No interesting event to report to the caller. */
2782 if ((options
& WNOHANG
))
2785 debug_printf ("WNOHANG set, no event found\n");
2787 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2791 /* Block until we get an event reported with SIGCHLD. */
2793 debug_printf ("sigsuspend'ing\n");
2795 sigsuspend (&prev_mask
);
2796 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2800 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2802 current_thread
= event_thread
;
2804 return lwpid_of (event_thread
);
2807 /* Wait for an event from child(ren) PTID. PTIDs can be:
2808 minus_one_ptid, to specify any child; a pid PTID, specifying all
2809 lwps of a thread group; or a PTID representing a single lwp. Store
2810 the stop status through the status pointer WSTAT. OPTIONS is
2811 passed to the waitpid call. Return 0 if no event was found and
2812 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2813 was found. Return the PID of the stopped child otherwise. */
2816 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2818 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2821 /* Select one LWP out of those that have events pending. */
2824 select_event_lwp (struct lwp_info
**orig_lp
)
2826 int random_selector
;
2827 struct thread_info
*event_thread
= NULL
;
2829 /* In all-stop, give preference to the LWP that is being
2830 single-stepped. There will be at most one, and it's the LWP that
2831 the core is most interested in. If we didn't do this, then we'd
2832 have to handle pending step SIGTRAPs somehow in case the core
2833 later continues the previously-stepped thread, otherwise we'd
2834 report the pending SIGTRAP, and the core, not having stepped the
2835 thread, wouldn't understand what the trap was for, and therefore
2836 would report it to the user as a random signal. */
2839 event_thread
= find_thread ([] (thread_info
*thread
)
2841 lwp_info
*lp
= get_thread_lwp (thread
);
2843 return (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2844 && thread
->last_resume_kind
== resume_step
2845 && lp
->status_pending_p
);
2848 if (event_thread
!= NULL
)
2851 debug_printf ("SEL: Select single-step %s\n",
2852 target_pid_to_str (ptid_of (event_thread
)));
2855 if (event_thread
== NULL
)
2857 /* No single-stepping LWP. Select one at random, out of those
2858 which have had events. */
2860 /* First see how many events we have. */
2862 for_each_thread ([&] (thread_info
*thread
)
2864 lwp_info
*lp
= get_thread_lwp (thread
);
2866 /* Count only resumed LWPs that have an event pending. */
2867 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2868 && lp
->status_pending_p
)
2871 gdb_assert (num_events
> 0);
2873 /* Now randomly pick a LWP out of those that have had
2875 random_selector
= (int)
2876 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2878 if (debug_threads
&& num_events
> 1)
2879 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2880 num_events
, random_selector
);
2882 event_thread
= find_thread ([&] (thread_info
*thread
)
2884 lwp_info
*lp
= get_thread_lwp (thread
);
2886 /* Select only resumed LWPs that have an event pending. */
2887 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2888 && lp
->status_pending_p
)
2889 if (random_selector
-- == 0)
2896 if (event_thread
!= NULL
)
2898 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2900 /* Switch the event LWP. */
2901 *orig_lp
= event_lp
;
2905 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2909 unsuspend_all_lwps (struct lwp_info
*except
)
2911 for_each_thread ([&] (thread_info
*thread
)
2913 lwp_info
*lwp
= get_thread_lwp (thread
);
2916 lwp_suspended_decr (lwp
);
2920 static void move_out_of_jump_pad_callback (thread_info
*thread
);
2921 static bool stuck_in_jump_pad_callback (thread_info
*thread
);
2922 static bool lwp_running (thread_info
*thread
);
2923 static ptid_t
linux_wait_1 (ptid_t ptid
,
2924 struct target_waitstatus
*ourstatus
,
2925 int target_options
);
2927 /* Stabilize threads (move out of jump pads).
2929 If a thread is midway collecting a fast tracepoint, we need to
2930 finish the collection and move it out of the jump pad before
2931 reporting the signal.
2933 This avoids recursion while collecting (when a signal arrives
2934 midway, and the signal handler itself collects), which would trash
2935 the trace buffer. In case the user set a breakpoint in a signal
2936 handler, this avoids the backtrace showing the jump pad, etc..
2937 Most importantly, there are certain things we can't do safely if
2938 threads are stopped in a jump pad (or in its callee's). For
2941 - starting a new trace run. A thread still collecting the
2942 previous run, could trash the trace buffer when resumed. The trace
2943 buffer control structures would have been reset but the thread had
2944 no way to tell. The thread could even midway memcpy'ing to the
2945 buffer, which would mean that when resumed, it would clobber the
2946 trace buffer that had been set for a new run.
2948 - we can't rewrite/reuse the jump pads for new tracepoints
2949 safely. Say you do tstart while a thread is stopped midway while
2950 collecting. When the thread is later resumed, it finishes the
2951 collection, and returns to the jump pad, to execute the original
2952 instruction that was under the tracepoint jump at the time the
2953 older run had been started. If the jump pad had been rewritten
2954 since for something else in the new run, the thread would now
2955 execute the wrong / random instructions. */
2958 linux_stabilize_threads (void)
2960 thread_info
*thread_stuck
= find_thread (stuck_in_jump_pad_callback
);
2962 if (thread_stuck
!= NULL
)
2965 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2966 lwpid_of (thread_stuck
));
2970 thread_info
*saved_thread
= current_thread
;
2972 stabilizing_threads
= 1;
2975 for_each_thread (move_out_of_jump_pad_callback
);
2977 /* Loop until all are stopped out of the jump pads. */
2978 while (find_thread (lwp_running
) != NULL
)
2980 struct target_waitstatus ourstatus
;
2981 struct lwp_info
*lwp
;
2984 /* Note that we go through the full wait even loop. While
2985 moving threads out of jump pad, we need to be able to step
2986 over internal breakpoints and such. */
2987 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2989 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2991 lwp
= get_thread_lwp (current_thread
);
2994 lwp_suspended_inc (lwp
);
2996 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2997 || current_thread
->last_resume_kind
== resume_stop
)
2999 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
3000 enqueue_one_deferred_signal (lwp
, &wstat
);
3005 unsuspend_all_lwps (NULL
);
3007 stabilizing_threads
= 0;
3009 current_thread
= saved_thread
;
3013 thread_stuck
= find_thread (stuck_in_jump_pad_callback
);
3015 if (thread_stuck
!= NULL
)
3016 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
3017 lwpid_of (thread_stuck
));
3021 /* Convenience function that is called when the kernel reports an
3022 event that is not passed out to GDB. */
3025 ignore_event (struct target_waitstatus
*ourstatus
)
3027 /* If we got an event, there may still be others, as a single
3028 SIGCHLD can indicate more than one child stopped. This forces
3029 another target_wait call. */
3032 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3036 /* Convenience function that is called when the kernel reports an exit
3037 event. This decides whether to report the event to GDB as a
3038 process exit event, a thread exit event, or to suppress the
3042 filter_exit_event (struct lwp_info
*event_child
,
3043 struct target_waitstatus
*ourstatus
)
3045 struct thread_info
*thread
= get_lwp_thread (event_child
);
3046 ptid_t ptid
= ptid_of (thread
);
3048 if (!last_thread_of_process_p (pid_of (thread
)))
3050 if (report_thread_events
)
3051 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
3053 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3055 delete_lwp (event_child
);
3060 /* Returns 1 if GDB is interested in any event_child syscalls. */
3063 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
3065 struct thread_info
*thread
= get_lwp_thread (event_child
);
3066 struct process_info
*proc
= get_thread_process (thread
);
3068 return !proc
->syscalls_to_catch
.empty ();
3071 /* Returns 1 if GDB is interested in the event_child syscall.
3072 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3075 gdb_catch_this_syscall_p (struct lwp_info
*event_child
)
3078 struct thread_info
*thread
= get_lwp_thread (event_child
);
3079 struct process_info
*proc
= get_thread_process (thread
);
3081 if (proc
->syscalls_to_catch
.empty ())
3084 if (proc
->syscalls_to_catch
[0] == ANY_SYSCALL
)
3087 get_syscall_trapinfo (event_child
, &sysno
);
3089 for (int iter
: proc
->syscalls_to_catch
)
3096 /* Wait for process, returns status. */
3099 linux_wait_1 (ptid_t ptid
,
3100 struct target_waitstatus
*ourstatus
, int target_options
)
3103 struct lwp_info
*event_child
;
3106 int step_over_finished
;
3107 int bp_explains_trap
;
3108 int maybe_internal_trap
;
3117 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
3120 /* Translate generic target options into linux options. */
3122 if (target_options
& TARGET_WNOHANG
)
3125 bp_explains_trap
= 0;
3128 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3130 auto status_pending_p_any
= [&] (thread_info
*thread
)
3132 return status_pending_p_callback (thread
, minus_one_ptid
);
3135 auto not_stopped
= [&] (thread_info
*thread
)
3137 return not_stopped_callback (thread
, minus_one_ptid
);
3140 /* Find a resumed LWP, if any. */
3141 if (find_thread (status_pending_p_any
) != NULL
)
3143 else if (find_thread (not_stopped
) != NULL
)
3148 if (ptid_equal (step_over_bkpt
, null_ptid
))
3149 pid
= linux_wait_for_event (ptid
, &w
, options
);
3153 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3154 target_pid_to_str (step_over_bkpt
));
3155 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3158 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3160 gdb_assert (target_options
& TARGET_WNOHANG
);
3164 debug_printf ("linux_wait_1 ret = null_ptid, "
3165 "TARGET_WAITKIND_IGNORE\n");
3169 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3176 debug_printf ("linux_wait_1 ret = null_ptid, "
3177 "TARGET_WAITKIND_NO_RESUMED\n");
3181 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3185 event_child
= get_thread_lwp (current_thread
);
3187 /* linux_wait_for_event only returns an exit status for the last
3188 child of a process. Report it. */
3189 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3193 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3194 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3198 debug_printf ("linux_wait_1 ret = %s, exited with "
3200 target_pid_to_str (ptid_of (current_thread
)),
3207 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3208 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3212 debug_printf ("linux_wait_1 ret = %s, terminated with "
3214 target_pid_to_str (ptid_of (current_thread
)),
3220 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3221 return filter_exit_event (event_child
, ourstatus
);
3223 return ptid_of (current_thread
);
3226 /* If step-over executes a breakpoint instruction, in the case of a
3227 hardware single step it means a gdb/gdbserver breakpoint had been
3228 planted on top of a permanent breakpoint, in the case of a software
3229 single step it may just mean that gdbserver hit the reinsert breakpoint.
3230 The PC has been adjusted by save_stop_reason to point at
3231 the breakpoint address.
3232 So in the case of the hardware single step advance the PC manually
3233 past the breakpoint and in the case of software single step advance only
3234 if it's not the single_step_breakpoint we are hitting.
3235 This avoids that a program would keep trapping a permanent breakpoint
3237 if (!ptid_equal (step_over_bkpt
, null_ptid
)
3238 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3239 && (event_child
->stepping
3240 || !single_step_breakpoint_inserted_here (event_child
->stop_pc
)))
3242 int increment_pc
= 0;
3243 int breakpoint_kind
= 0;
3244 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3247 the_target
->breakpoint_kind_from_current_state (&stop_pc
);
3248 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3252 debug_printf ("step-over for %s executed software breakpoint\n",
3253 target_pid_to_str (ptid_of (current_thread
)));
3256 if (increment_pc
!= 0)
3258 struct regcache
*regcache
3259 = get_thread_regcache (current_thread
, 1);
3261 event_child
->stop_pc
+= increment_pc
;
3262 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3264 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3265 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3269 /* If this event was not handled before, and is not a SIGTRAP, we
3270 report it. SIGILL and SIGSEGV are also treated as traps in case
3271 a breakpoint is inserted at the current PC. If this target does
3272 not support internal breakpoints at all, we also report the
3273 SIGTRAP without further processing; it's of no concern to us. */
3275 = (supports_breakpoints ()
3276 && (WSTOPSIG (w
) == SIGTRAP
3277 || ((WSTOPSIG (w
) == SIGILL
3278 || WSTOPSIG (w
) == SIGSEGV
)
3279 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3281 if (maybe_internal_trap
)
3283 /* Handle anything that requires bookkeeping before deciding to
3284 report the event or continue waiting. */
3286 /* First check if we can explain the SIGTRAP with an internal
3287 breakpoint, or if we should possibly report the event to GDB.
3288 Do this before anything that may remove or insert a
3290 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3292 /* We have a SIGTRAP, possibly a step-over dance has just
3293 finished. If so, tweak the state machine accordingly,
3294 reinsert breakpoints and delete any single-step
3296 step_over_finished
= finish_step_over (event_child
);
3298 /* Now invoke the callbacks of any internal breakpoints there. */
3299 check_breakpoints (event_child
->stop_pc
);
3301 /* Handle tracepoint data collecting. This may overflow the
3302 trace buffer, and cause a tracing stop, removing
3304 trace_event
= handle_tracepoints (event_child
);
3306 if (bp_explains_trap
)
3309 debug_printf ("Hit a gdbserver breakpoint.\n");
3314 /* We have some other signal, possibly a step-over dance was in
3315 progress, and it should be cancelled too. */
3316 step_over_finished
= finish_step_over (event_child
);
3319 /* We have all the data we need. Either report the event to GDB, or
3320 resume threads and keep waiting for more. */
3322 /* If we're collecting a fast tracepoint, finish the collection and
3323 move out of the jump pad before delivering a signal. See
3324 linux_stabilize_threads. */
3327 && WSTOPSIG (w
) != SIGTRAP
3328 && supports_fast_tracepoints ()
3329 && agent_loaded_p ())
3332 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3333 "to defer or adjust it.\n",
3334 WSTOPSIG (w
), lwpid_of (current_thread
));
3336 /* Allow debugging the jump pad itself. */
3337 if (current_thread
->last_resume_kind
!= resume_step
3338 && maybe_move_out_of_jump_pad (event_child
, &w
))
3340 enqueue_one_deferred_signal (event_child
, &w
);
3343 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3344 WSTOPSIG (w
), lwpid_of (current_thread
));
3346 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3350 return ignore_event (ourstatus
);
3354 if (event_child
->collecting_fast_tracepoint
3355 != fast_tpoint_collect_result::not_collecting
)
3358 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3359 "Check if we're already there.\n",
3360 lwpid_of (current_thread
),
3361 (int) event_child
->collecting_fast_tracepoint
);
3365 event_child
->collecting_fast_tracepoint
3366 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3368 if (event_child
->collecting_fast_tracepoint
3369 != fast_tpoint_collect_result::before_insn
)
3371 /* No longer need this breakpoint. */
3372 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3375 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3376 "stopping all threads momentarily.\n");
3378 /* Other running threads could hit this breakpoint.
3379 We don't handle moribund locations like GDB does,
3380 instead we always pause all threads when removing
3381 breakpoints, so that any step-over or
3382 decr_pc_after_break adjustment is always taken
3383 care of while the breakpoint is still
3385 stop_all_lwps (1, event_child
);
3387 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3388 event_child
->exit_jump_pad_bkpt
= NULL
;
3390 unstop_all_lwps (1, event_child
);
3392 gdb_assert (event_child
->suspended
>= 0);
3396 if (event_child
->collecting_fast_tracepoint
3397 == fast_tpoint_collect_result::not_collecting
)
3400 debug_printf ("fast tracepoint finished "
3401 "collecting successfully.\n");
3403 /* We may have a deferred signal to report. */
3404 if (dequeue_one_deferred_signal (event_child
, &w
))
3407 debug_printf ("dequeued one signal.\n");
3412 debug_printf ("no deferred signals.\n");
3414 if (stabilizing_threads
)
3416 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3417 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3421 debug_printf ("linux_wait_1 ret = %s, stopped "
3422 "while stabilizing threads\n",
3423 target_pid_to_str (ptid_of (current_thread
)));
3427 return ptid_of (current_thread
);
3433 /* Check whether GDB would be interested in this event. */
3435 /* Check if GDB is interested in this syscall. */
3437 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3438 && !gdb_catch_this_syscall_p (event_child
))
3442 debug_printf ("Ignored syscall for LWP %ld.\n",
3443 lwpid_of (current_thread
));
3446 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3451 return ignore_event (ourstatus
);
3454 /* If GDB is not interested in this signal, don't stop other
3455 threads, and don't report it to GDB. Just resume the inferior
3456 right away. We do this for threading-related signals as well as
3457 any that GDB specifically requested we ignore. But never ignore
3458 SIGSTOP if we sent it ourselves, and do not ignore signals when
3459 stepping - they may require special handling to skip the signal
3460 handler. Also never ignore signals that could be caused by a
3463 && current_thread
->last_resume_kind
!= resume_step
3465 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3466 (current_process ()->priv
->thread_db
!= NULL
3467 && (WSTOPSIG (w
) == __SIGRTMIN
3468 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3471 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3472 && !(WSTOPSIG (w
) == SIGSTOP
3473 && current_thread
->last_resume_kind
== resume_stop
)
3474 && !linux_wstatus_maybe_breakpoint (w
))))
3476 siginfo_t info
, *info_p
;
3479 debug_printf ("Ignored signal %d for LWP %ld.\n",
3480 WSTOPSIG (w
), lwpid_of (current_thread
));
3482 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3483 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3488 if (step_over_finished
)
3490 /* We cancelled this thread's step-over above. We still
3491 need to unsuspend all other LWPs, and set them back
3492 running again while the signal handler runs. */
3493 unsuspend_all_lwps (event_child
);
3495 /* Enqueue the pending signal info so that proceed_all_lwps
3497 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3499 proceed_all_lwps ();
3503 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3504 WSTOPSIG (w
), info_p
);
3510 return ignore_event (ourstatus
);
3513 /* Note that all addresses are always "out of the step range" when
3514 there's no range to begin with. */
3515 in_step_range
= lwp_in_step_range (event_child
);
3517 /* If GDB wanted this thread to single step, and the thread is out
3518 of the step range, we always want to report the SIGTRAP, and let
3519 GDB handle it. Watchpoints should always be reported. So should
3520 signals we can't explain. A SIGTRAP we can't explain could be a
3521 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3522 do, we're be able to handle GDB breakpoints on top of internal
3523 breakpoints, by handling the internal breakpoint and still
3524 reporting the event to GDB. If we don't, we're out of luck, GDB
3525 won't see the breakpoint hit. If we see a single-step event but
3526 the thread should be continuing, don't pass the trap to gdb.
3527 That indicates that we had previously finished a single-step but
3528 left the single-step pending -- see
3529 complete_ongoing_step_over. */
3530 report_to_gdb
= (!maybe_internal_trap
3531 || (current_thread
->last_resume_kind
== resume_step
3533 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3535 && !bp_explains_trap
3537 && !step_over_finished
3538 && !(current_thread
->last_resume_kind
== resume_continue
3539 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3540 || (gdb_breakpoint_here (event_child
->stop_pc
)
3541 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3542 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3543 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3545 run_breakpoint_commands (event_child
->stop_pc
);
3547 /* We found no reason GDB would want us to stop. We either hit one
3548 of our own breakpoints, or finished an internal step GDB
3549 shouldn't know about. */
3554 if (bp_explains_trap
)
3555 debug_printf ("Hit a gdbserver breakpoint.\n");
3556 if (step_over_finished
)
3557 debug_printf ("Step-over finished.\n");
3559 debug_printf ("Tracepoint event.\n");
3560 if (lwp_in_step_range (event_child
))
3561 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3562 paddress (event_child
->stop_pc
),
3563 paddress (event_child
->step_range_start
),
3564 paddress (event_child
->step_range_end
));
3567 /* We're not reporting this breakpoint to GDB, so apply the
3568 decr_pc_after_break adjustment to the inferior's regcache
3571 if (the_low_target
.set_pc
!= NULL
)
3573 struct regcache
*regcache
3574 = get_thread_regcache (current_thread
, 1);
3575 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3578 if (step_over_finished
)
3580 /* If we have finished stepping over a breakpoint, we've
3581 stopped and suspended all LWPs momentarily except the
3582 stepping one. This is where we resume them all again.
3583 We're going to keep waiting, so use proceed, which
3584 handles stepping over the next breakpoint. */
3585 unsuspend_all_lwps (event_child
);
3589 /* Remove the single-step breakpoints if any. Note that
3590 there isn't single-step breakpoint if we finished stepping
3592 if (can_software_single_step ()
3593 && has_single_step_breakpoints (current_thread
))
3595 stop_all_lwps (0, event_child
);
3596 delete_single_step_breakpoints (current_thread
);
3597 unstop_all_lwps (0, event_child
);
3602 debug_printf ("proceeding all threads.\n");
3603 proceed_all_lwps ();
3608 return ignore_event (ourstatus
);
3613 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3616 = target_waitstatus_to_string (&event_child
->waitstatus
);
3618 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3619 lwpid_of (get_lwp_thread (event_child
)), str
.c_str ());
3621 if (current_thread
->last_resume_kind
== resume_step
)
3623 if (event_child
->step_range_start
== event_child
->step_range_end
)
3624 debug_printf ("GDB wanted to single-step, reporting event.\n");
3625 else if (!lwp_in_step_range (event_child
))
3626 debug_printf ("Out of step range, reporting event.\n");
3628 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3629 debug_printf ("Stopped by watchpoint.\n");
3630 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3631 debug_printf ("Stopped by GDB breakpoint.\n");
3633 debug_printf ("Hit a non-gdbserver trap event.\n");
3636 /* Alright, we're going to report a stop. */
3638 /* Remove single-step breakpoints. */
3639 if (can_software_single_step ())
3641 /* Remove single-step breakpoints or not. It it is true, stop all
3642 lwps, so that other threads won't hit the breakpoint in the
3644 int remove_single_step_breakpoints_p
= 0;
3648 remove_single_step_breakpoints_p
3649 = has_single_step_breakpoints (current_thread
);
3653 /* In all-stop, a stop reply cancels all previous resume
3654 requests. Delete all single-step breakpoints. */
3656 find_thread ([&] (thread_info
*thread
) {
3657 if (has_single_step_breakpoints (thread
))
3659 remove_single_step_breakpoints_p
= 1;
3667 if (remove_single_step_breakpoints_p
)
3669 /* If we remove single-step breakpoints from memory, stop all lwps,
3670 so that other threads won't hit the breakpoint in the staled
3672 stop_all_lwps (0, event_child
);
3676 gdb_assert (has_single_step_breakpoints (current_thread
));
3677 delete_single_step_breakpoints (current_thread
);
3681 for_each_thread ([] (thread_info
*thread
){
3682 if (has_single_step_breakpoints (thread
))
3683 delete_single_step_breakpoints (thread
);
3687 unstop_all_lwps (0, event_child
);
3691 if (!stabilizing_threads
)
3693 /* In all-stop, stop all threads. */
3695 stop_all_lwps (0, NULL
);
3697 if (step_over_finished
)
3701 /* If we were doing a step-over, all other threads but
3702 the stepping one had been paused in start_step_over,
3703 with their suspend counts incremented. We don't want
3704 to do a full unstop/unpause, because we're in
3705 all-stop mode (so we want threads stopped), but we
3706 still need to unsuspend the other threads, to
3707 decrement their `suspended' count back. */
3708 unsuspend_all_lwps (event_child
);
3712 /* If we just finished a step-over, then all threads had
3713 been momentarily paused. In all-stop, that's fine,
3714 we want threads stopped by now anyway. In non-stop,
3715 we need to re-resume threads that GDB wanted to be
3717 unstop_all_lwps (1, event_child
);
3721 /* If we're not waiting for a specific LWP, choose an event LWP
3722 from among those that have had events. Giving equal priority
3723 to all LWPs that have had events helps prevent
3725 if (ptid_equal (ptid
, minus_one_ptid
))
3727 event_child
->status_pending_p
= 1;
3728 event_child
->status_pending
= w
;
3730 select_event_lwp (&event_child
);
3732 /* current_thread and event_child must stay in sync. */
3733 current_thread
= get_lwp_thread (event_child
);
3735 event_child
->status_pending_p
= 0;
3736 w
= event_child
->status_pending
;
3740 /* Stabilize threads (move out of jump pads). */
3742 stabilize_threads ();
3746 /* If we just finished a step-over, then all threads had been
3747 momentarily paused. In all-stop, that's fine, we want
3748 threads stopped by now anyway. In non-stop, we need to
3749 re-resume threads that GDB wanted to be running. */
3750 if (step_over_finished
)
3751 unstop_all_lwps (1, event_child
);
3754 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3756 /* If the reported event is an exit, fork, vfork or exec, let
3759 /* Break the unreported fork relationship chain. */
3760 if (event_child
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
3761 || event_child
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
)
3763 event_child
->fork_relative
->fork_relative
= NULL
;
3764 event_child
->fork_relative
= NULL
;
3767 *ourstatus
= event_child
->waitstatus
;
3768 /* Clear the event lwp's waitstatus since we handled it already. */
3769 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3772 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3774 /* Now that we've selected our final event LWP, un-adjust its PC if
3775 it was a software breakpoint, and the client doesn't know we can
3776 adjust the breakpoint ourselves. */
3777 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3778 && !swbreak_feature
)
3780 int decr_pc
= the_low_target
.decr_pc_after_break
;
3784 struct regcache
*regcache
3785 = get_thread_regcache (current_thread
, 1);
3786 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3790 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3792 get_syscall_trapinfo (event_child
,
3793 &ourstatus
->value
.syscall_number
);
3794 ourstatus
->kind
= event_child
->syscall_state
;
3796 else if (current_thread
->last_resume_kind
== resume_stop
3797 && WSTOPSIG (w
) == SIGSTOP
)
3799 /* A thread that has been requested to stop by GDB with vCont;t,
3800 and it stopped cleanly, so report as SIG0. The use of
3801 SIGSTOP is an implementation detail. */
3802 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3804 else if (current_thread
->last_resume_kind
== resume_stop
3805 && WSTOPSIG (w
) != SIGSTOP
)
3807 /* A thread that has been requested to stop by GDB with vCont;t,
3808 but, it stopped for other reasons. */
3809 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3811 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3813 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3816 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3820 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3821 target_pid_to_str (ptid_of (current_thread
)),
3822 ourstatus
->kind
, ourstatus
->value
.sig
);
3826 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3827 return filter_exit_event (event_child
, ourstatus
);
3829 return ptid_of (current_thread
);
3832 /* Get rid of any pending event in the pipe. */
3834 async_file_flush (void)
3840 ret
= read (linux_event_pipe
[0], &buf
, 1);
3841 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3844 /* Put something in the pipe, so the event loop wakes up. */
3846 async_file_mark (void)
3850 async_file_flush ();
3853 ret
= write (linux_event_pipe
[1], "+", 1);
3854 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3856 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3857 be awakened anyway. */
3861 linux_wait (ptid_t ptid
,
3862 struct target_waitstatus
*ourstatus
, int target_options
)
3866 /* Flush the async file first. */
3867 if (target_is_async_p ())
3868 async_file_flush ();
3872 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3874 while ((target_options
& TARGET_WNOHANG
) == 0
3875 && ptid_equal (event_ptid
, null_ptid
)
3876 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3878 /* If at least one stop was reported, there may be more. A single
3879 SIGCHLD can signal more than one child stop. */
3880 if (target_is_async_p ()
3881 && (target_options
& TARGET_WNOHANG
) != 0
3882 && !ptid_equal (event_ptid
, null_ptid
))
3888 /* Send a signal to an LWP. */
3891 kill_lwp (unsigned long lwpid
, int signo
)
3896 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3897 if (errno
== ENOSYS
)
3899 /* If tkill fails, then we are not using nptl threads, a
3900 configuration we no longer support. */
3901 perror_with_name (("tkill"));
3907 linux_stop_lwp (struct lwp_info
*lwp
)
3913 send_sigstop (struct lwp_info
*lwp
)
3917 pid
= lwpid_of (get_lwp_thread (lwp
));
3919 /* If we already have a pending stop signal for this process, don't
3921 if (lwp
->stop_expected
)
3924 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3930 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3932 lwp
->stop_expected
= 1;
3933 kill_lwp (pid
, SIGSTOP
);
3937 send_sigstop (thread_info
*thread
, lwp_info
*except
)
3939 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3941 /* Ignore EXCEPT. */
3951 /* Increment the suspend count of an LWP, and stop it, if not stopped
3954 suspend_and_send_sigstop (thread_info
*thread
, lwp_info
*except
)
3956 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3958 /* Ignore EXCEPT. */
3962 lwp_suspended_inc (lwp
);
3964 send_sigstop (thread
, except
);
3968 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3970 /* Store the exit status for later. */
3971 lwp
->status_pending_p
= 1;
3972 lwp
->status_pending
= wstat
;
3974 /* Store in waitstatus as well, as there's nothing else to process
3976 if (WIFEXITED (wstat
))
3978 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3979 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3981 else if (WIFSIGNALED (wstat
))
3983 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3984 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3987 /* Prevent trying to stop it. */
3990 /* No further stops are expected from a dead lwp. */
3991 lwp
->stop_expected
= 0;
3994 /* Return true if LWP has exited already, and has a pending exit event
3995 to report to GDB. */
3998 lwp_is_marked_dead (struct lwp_info
*lwp
)
4000 return (lwp
->status_pending_p
4001 && (WIFEXITED (lwp
->status_pending
)
4002 || WIFSIGNALED (lwp
->status_pending
)));
4005 /* Wait for all children to stop for the SIGSTOPs we just queued. */
4008 wait_for_sigstop (void)
4010 struct thread_info
*saved_thread
;
4015 saved_thread
= current_thread
;
4016 if (saved_thread
!= NULL
)
4017 saved_tid
= saved_thread
->id
;
4019 saved_tid
= null_ptid
; /* avoid bogus unused warning */
4022 debug_printf ("wait_for_sigstop: pulling events\n");
4024 /* Passing NULL_PTID as filter indicates we want all events to be
4025 left pending. Eventually this returns when there are no
4026 unwaited-for children left. */
4027 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4029 gdb_assert (ret
== -1);
4031 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
4032 current_thread
= saved_thread
;
4036 debug_printf ("Previously current thread died.\n");
4038 /* We can't change the current inferior behind GDB's back,
4039 otherwise, a subsequent command may apply to the wrong
4041 current_thread
= NULL
;
4045 /* Returns true if THREAD is stopped in a jump pad, and we can't
4046 move it out, because we need to report the stop event to GDB. For
4047 example, if the user puts a breakpoint in the jump pad, it's
4048 because she wants to debug it. */
4051 stuck_in_jump_pad_callback (thread_info
*thread
)
4053 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4055 if (lwp
->suspended
!= 0)
4057 internal_error (__FILE__
, __LINE__
,
4058 "LWP %ld is suspended, suspended=%d\n",
4059 lwpid_of (thread
), lwp
->suspended
);
4061 gdb_assert (lwp
->stopped
);
4063 /* Allow debugging the jump pad, gdb_collect, etc.. */
4064 return (supports_fast_tracepoints ()
4065 && agent_loaded_p ()
4066 && (gdb_breakpoint_here (lwp
->stop_pc
)
4067 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
4068 || thread
->last_resume_kind
== resume_step
)
4069 && (linux_fast_tracepoint_collecting (lwp
, NULL
)
4070 != fast_tpoint_collect_result::not_collecting
));
4074 move_out_of_jump_pad_callback (thread_info
*thread
)
4076 struct thread_info
*saved_thread
;
4077 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4080 if (lwp
->suspended
!= 0)
4082 internal_error (__FILE__
, __LINE__
,
4083 "LWP %ld is suspended, suspended=%d\n",
4084 lwpid_of (thread
), lwp
->suspended
);
4086 gdb_assert (lwp
->stopped
);
4088 /* For gdb_breakpoint_here. */
4089 saved_thread
= current_thread
;
4090 current_thread
= thread
;
4092 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
4094 /* Allow debugging the jump pad, gdb_collect, etc. */
4095 if (!gdb_breakpoint_here (lwp
->stop_pc
)
4096 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
4097 && thread
->last_resume_kind
!= resume_step
4098 && maybe_move_out_of_jump_pad (lwp
, wstat
))
4101 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
4106 lwp
->status_pending_p
= 0;
4107 enqueue_one_deferred_signal (lwp
, wstat
);
4110 debug_printf ("Signal %d for LWP %ld deferred "
4112 WSTOPSIG (*wstat
), lwpid_of (thread
));
4115 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
4118 lwp_suspended_inc (lwp
);
4120 current_thread
= saved_thread
;
4124 lwp_running (thread_info
*thread
)
4126 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4128 if (lwp_is_marked_dead (lwp
))
4131 return !lwp
->stopped
;
4134 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4135 If SUSPEND, then also increase the suspend count of every LWP,
4139 stop_all_lwps (int suspend
, struct lwp_info
*except
)
4141 /* Should not be called recursively. */
4142 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
4147 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4148 suspend
? "stop-and-suspend" : "stop",
4150 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
4154 stopping_threads
= (suspend
4155 ? STOPPING_AND_SUSPENDING_THREADS
4156 : STOPPING_THREADS
);
4159 for_each_thread ([&] (thread_info
*thread
)
4161 suspend_and_send_sigstop (thread
, except
);
4164 for_each_thread ([&] (thread_info
*thread
)
4166 send_sigstop (thread
, except
);
4169 wait_for_sigstop ();
4170 stopping_threads
= NOT_STOPPING_THREADS
;
4174 debug_printf ("stop_all_lwps done, setting stopping_threads "
4175 "back to !stopping\n");
4180 /* Enqueue one signal in the chain of signals which need to be
4181 delivered to this process on next resume. */
4184 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4186 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4188 p_sig
->prev
= lwp
->pending_signals
;
4189 p_sig
->signal
= signal
;
4191 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4193 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4194 lwp
->pending_signals
= p_sig
;
4197 /* Install breakpoints for software single stepping. */
4200 install_software_single_step_breakpoints (struct lwp_info
*lwp
)
4202 struct thread_info
*thread
= get_lwp_thread (lwp
);
4203 struct regcache
*regcache
= get_thread_regcache (thread
, 1);
4204 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
4206 current_thread
= thread
;
4207 std::vector
<CORE_ADDR
> next_pcs
= the_low_target
.get_next_pcs (regcache
);
4209 for (CORE_ADDR pc
: next_pcs
)
4210 set_single_step_breakpoint (pc
, current_ptid
);
4212 do_cleanups (old_chain
);
4215 /* Single step via hardware or software single step.
4216 Return 1 if hardware single stepping, 0 if software single stepping
4217 or can't single step. */
4220 single_step (struct lwp_info
* lwp
)
4224 if (can_hardware_single_step ())
4228 else if (can_software_single_step ())
4230 install_software_single_step_breakpoints (lwp
);
4236 debug_printf ("stepping is not implemented on this target");
4242 /* The signal can be delivered to the inferior if we are not trying to
4243 finish a fast tracepoint collect. Since signal can be delivered in
4244 the step-over, the program may go to signal handler and trap again
4245 after return from the signal handler. We can live with the spurious
4249 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
4251 return (lwp
->collecting_fast_tracepoint
4252 == fast_tpoint_collect_result::not_collecting
);
4255 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4256 SIGNAL is nonzero, give it that signal. */
4259 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
4260 int step
, int signal
, siginfo_t
*info
)
4262 struct thread_info
*thread
= get_lwp_thread (lwp
);
4263 struct thread_info
*saved_thread
;
4265 struct process_info
*proc
= get_thread_process (thread
);
4267 /* Note that target description may not be initialised
4268 (proc->tdesc == NULL) at this point because the program hasn't
4269 stopped at the first instruction yet. It means GDBserver skips
4270 the extra traps from the wrapper program (see option --wrapper).
4271 Code in this function that requires register access should be
4272 guarded by proc->tdesc == NULL or something else. */
4274 if (lwp
->stopped
== 0)
4277 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4279 fast_tpoint_collect_result fast_tp_collecting
4280 = lwp
->collecting_fast_tracepoint
;
4282 gdb_assert (!stabilizing_threads
4283 || (fast_tp_collecting
4284 != fast_tpoint_collect_result::not_collecting
));
4286 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4287 user used the "jump" command, or "set $pc = foo"). */
4288 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4290 /* Collecting 'while-stepping' actions doesn't make sense
4292 release_while_stepping_state_list (thread
);
4295 /* If we have pending signals or status, and a new signal, enqueue the
4296 signal. Also enqueue the signal if it can't be delivered to the
4297 inferior right now. */
4299 && (lwp
->status_pending_p
4300 || lwp
->pending_signals
!= NULL
4301 || !lwp_signal_can_be_delivered (lwp
)))
4303 enqueue_pending_signal (lwp
, signal
, info
);
4305 /* Postpone any pending signal. It was enqueued above. */
4309 if (lwp
->status_pending_p
)
4312 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4313 " has pending status\n",
4314 lwpid_of (thread
), step
? "step" : "continue",
4315 lwp
->stop_expected
? "expected" : "not expected");
4319 saved_thread
= current_thread
;
4320 current_thread
= thread
;
4322 /* This bit needs some thinking about. If we get a signal that
4323 we must report while a single-step reinsert is still pending,
4324 we often end up resuming the thread. It might be better to
4325 (ew) allow a stack of pending events; then we could be sure that
4326 the reinsert happened right away and not lose any signals.
4328 Making this stack would also shrink the window in which breakpoints are
4329 uninserted (see comment in linux_wait_for_lwp) but not enough for
4330 complete correctness, so it won't solve that problem. It may be
4331 worthwhile just to solve this one, however. */
4332 if (lwp
->bp_reinsert
!= 0)
4335 debug_printf (" pending reinsert at 0x%s\n",
4336 paddress (lwp
->bp_reinsert
));
4338 if (can_hardware_single_step ())
4340 if (fast_tp_collecting
== fast_tpoint_collect_result::not_collecting
)
4343 warning ("BAD - reinserting but not stepping.");
4345 warning ("BAD - reinserting and suspended(%d).",
4350 step
= maybe_hw_step (thread
);
4353 if (fast_tp_collecting
== fast_tpoint_collect_result::before_insn
)
4356 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4357 " (exit-jump-pad-bkpt)\n",
4360 else if (fast_tp_collecting
== fast_tpoint_collect_result::at_insn
)
4363 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4364 " single-stepping\n",
4367 if (can_hardware_single_step ())
4371 internal_error (__FILE__
, __LINE__
,
4372 "moving out of jump pad single-stepping"
4373 " not implemented on this target");
4377 /* If we have while-stepping actions in this thread set it stepping.
4378 If we have a signal to deliver, it may or may not be set to
4379 SIG_IGN, we don't know. Assume so, and allow collecting
4380 while-stepping into a signal handler. A possible smart thing to
4381 do would be to set an internal breakpoint at the signal return
4382 address, continue, and carry on catching this while-stepping
4383 action only when that breakpoint is hit. A future
4385 if (thread
->while_stepping
!= NULL
)
4388 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4391 step
= single_step (lwp
);
4394 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4396 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4398 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4402 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4403 (long) lwp
->stop_pc
);
4407 /* If we have pending signals, consume one if it can be delivered to
4409 if (lwp
->pending_signals
!= NULL
&& lwp_signal_can_be_delivered (lwp
))
4411 struct pending_signals
**p_sig
;
4413 p_sig
= &lwp
->pending_signals
;
4414 while ((*p_sig
)->prev
!= NULL
)
4415 p_sig
= &(*p_sig
)->prev
;
4417 signal
= (*p_sig
)->signal
;
4418 if ((*p_sig
)->info
.si_signo
!= 0)
4419 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4427 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4428 lwpid_of (thread
), step
? "step" : "continue", signal
,
4429 lwp
->stop_expected
? "expected" : "not expected");
4431 if (the_low_target
.prepare_to_resume
!= NULL
)
4432 the_low_target
.prepare_to_resume (lwp
);
4434 regcache_invalidate_thread (thread
);
4436 lwp
->stepping
= step
;
4438 ptrace_request
= PTRACE_SINGLESTEP
;
4439 else if (gdb_catching_syscalls_p (lwp
))
4440 ptrace_request
= PTRACE_SYSCALL
;
4442 ptrace_request
= PTRACE_CONT
;
4443 ptrace (ptrace_request
,
4445 (PTRACE_TYPE_ARG3
) 0,
4446 /* Coerce to a uintptr_t first to avoid potential gcc warning
4447 of coercing an 8 byte integer to a 4 byte pointer. */
4448 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4450 current_thread
= saved_thread
;
4452 perror_with_name ("resuming thread");
4454 /* Successfully resumed. Clear state that no longer makes sense,
4455 and mark the LWP as running. Must not do this before resuming
4456 otherwise if that fails other code will be confused. E.g., we'd
4457 later try to stop the LWP and hang forever waiting for a stop
4458 status. Note that we must not throw after this is cleared,
4459 otherwise handle_zombie_lwp_error would get confused. */
4461 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4464 /* Called when we try to resume a stopped LWP and that errors out. If
4465 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4466 or about to become), discard the error, clear any pending status
4467 the LWP may have, and return true (we'll collect the exit status
4468 soon enough). Otherwise, return false. */
4471 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4473 struct thread_info
*thread
= get_lwp_thread (lp
);
4475 /* If we get an error after resuming the LWP successfully, we'd
4476 confuse !T state for the LWP being gone. */
4477 gdb_assert (lp
->stopped
);
4479 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4480 because even if ptrace failed with ESRCH, the tracee may be "not
4481 yet fully dead", but already refusing ptrace requests. In that
4482 case the tracee has 'R (Running)' state for a little bit
4483 (observed in Linux 3.18). See also the note on ESRCH in the
4484 ptrace(2) man page. Instead, check whether the LWP has any state
4485 other than ptrace-stopped. */
4487 /* Don't assume anything if /proc/PID/status can't be read. */
4488 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4490 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4491 lp
->status_pending_p
= 0;
4497 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4498 disappears while we try to resume it. */
4501 linux_resume_one_lwp (struct lwp_info
*lwp
,
4502 int step
, int signal
, siginfo_t
*info
)
4506 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4508 CATCH (ex
, RETURN_MASK_ERROR
)
4510 if (!check_ptrace_stopped_lwp_gone (lwp
))
4511 throw_exception (ex
);
4516 /* This function is called once per thread via for_each_thread.
4517 We look up which resume request applies to THREAD and mark it with a
4518 pointer to the appropriate resume request.
4520 This algorithm is O(threads * resume elements), but resume elements
4521 is small (and will remain small at least until GDB supports thread
4525 linux_set_resume_request (thread_info
*thread
, thread_resume
*resume
, size_t n
)
4527 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4529 for (int ndx
= 0; ndx
< n
; ndx
++)
4531 ptid_t ptid
= resume
[ndx
].thread
;
4532 if (ptid_equal (ptid
, minus_one_ptid
)
4533 || ptid
== thread
->id
4534 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4536 || (ptid_get_pid (ptid
) == pid_of (thread
)
4537 && (ptid_is_pid (ptid
)
4538 || ptid_get_lwp (ptid
) == -1)))
4540 if (resume
[ndx
].kind
== resume_stop
4541 && thread
->last_resume_kind
== resume_stop
)
4544 debug_printf ("already %s LWP %ld at GDB's request\n",
4545 (thread
->last_status
.kind
4546 == TARGET_WAITKIND_STOPPED
)
4554 /* Ignore (wildcard) resume requests for already-resumed
4556 if (resume
[ndx
].kind
!= resume_stop
4557 && thread
->last_resume_kind
!= resume_stop
)
4560 debug_printf ("already %s LWP %ld at GDB's request\n",
4561 (thread
->last_resume_kind
4569 /* Don't let wildcard resumes resume fork children that GDB
4570 does not yet know are new fork children. */
4571 if (lwp
->fork_relative
!= NULL
)
4573 struct lwp_info
*rel
= lwp
->fork_relative
;
4575 if (rel
->status_pending_p
4576 && (rel
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
4577 || rel
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
))
4580 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4586 /* If the thread has a pending event that has already been
4587 reported to GDBserver core, but GDB has not pulled the
4588 event out of the vStopped queue yet, likewise, ignore the
4589 (wildcard) resume request. */
4590 if (in_queued_stop_replies (thread
->id
))
4593 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4598 lwp
->resume
= &resume
[ndx
];
4599 thread
->last_resume_kind
= lwp
->resume
->kind
;
4601 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4602 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4604 /* If we had a deferred signal to report, dequeue one now.
4605 This can happen if LWP gets more than one signal while
4606 trying to get out of a jump pad. */
4608 && !lwp
->status_pending_p
4609 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4611 lwp
->status_pending_p
= 1;
4614 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4615 "leaving status pending.\n",
4616 WSTOPSIG (lwp
->status_pending
),
4624 /* No resume action for this thread. */
4628 /* find_thread callback for linux_resume. Return true if this lwp has an
4629 interesting status pending. */
4632 resume_status_pending_p (thread_info
*thread
)
4634 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4636 /* LWPs which will not be resumed are not interesting, because
4637 we might not wait for them next time through linux_wait. */
4638 if (lwp
->resume
== NULL
)
4641 return thread_still_has_status_pending_p (thread
);
4644 /* Return 1 if this lwp that GDB wants running is stopped at an
4645 internal breakpoint that we need to step over. It assumes that any
4646 required STOP_PC adjustment has already been propagated to the
4647 inferior's regcache. */
4650 need_step_over_p (thread_info
*thread
)
4652 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4653 struct thread_info
*saved_thread
;
4655 struct process_info
*proc
= get_thread_process (thread
);
4657 /* GDBserver is skipping the extra traps from the wrapper program,
4658 don't have to do step over. */
4659 if (proc
->tdesc
== NULL
)
4662 /* LWPs which will not be resumed are not interesting, because we
4663 might not wait for them next time through linux_wait. */
4668 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4673 if (thread
->last_resume_kind
== resume_stop
)
4676 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4682 gdb_assert (lwp
->suspended
>= 0);
4687 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4692 if (lwp
->status_pending_p
)
4695 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4701 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4705 /* If the PC has changed since we stopped, then don't do anything,
4706 and let the breakpoint/tracepoint be hit. This happens if, for
4707 instance, GDB handled the decr_pc_after_break subtraction itself,
4708 GDB is OOL stepping this thread, or the user has issued a "jump"
4709 command, or poked thread's registers herself. */
4710 if (pc
!= lwp
->stop_pc
)
4713 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4714 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4716 paddress (lwp
->stop_pc
), paddress (pc
));
4720 /* On software single step target, resume the inferior with signal
4721 rather than stepping over. */
4722 if (can_software_single_step ()
4723 && lwp
->pending_signals
!= NULL
4724 && lwp_signal_can_be_delivered (lwp
))
4727 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4734 saved_thread
= current_thread
;
4735 current_thread
= thread
;
4737 /* We can only step over breakpoints we know about. */
4738 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4740 /* Don't step over a breakpoint that GDB expects to hit
4741 though. If the condition is being evaluated on the target's side
4742 and it evaluate to false, step over this breakpoint as well. */
4743 if (gdb_breakpoint_here (pc
)
4744 && gdb_condition_true_at_breakpoint (pc
)
4745 && gdb_no_commands_at_breakpoint (pc
))
4748 debug_printf ("Need step over [LWP %ld]? yes, but found"
4749 " GDB breakpoint at 0x%s; skipping step over\n",
4750 lwpid_of (thread
), paddress (pc
));
4752 current_thread
= saved_thread
;
4758 debug_printf ("Need step over [LWP %ld]? yes, "
4759 "found breakpoint at 0x%s\n",
4760 lwpid_of (thread
), paddress (pc
));
4762 /* We've found an lwp that needs stepping over --- return 1 so
4763 that find_thread stops looking. */
4764 current_thread
= saved_thread
;
4770 current_thread
= saved_thread
;
4773 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4775 lwpid_of (thread
), paddress (pc
));
4780 /* Start a step-over operation on LWP. When LWP stopped at a
4781 breakpoint, to make progress, we need to remove the breakpoint out
4782 of the way. If we let other threads run while we do that, they may
4783 pass by the breakpoint location and miss hitting it. To avoid
4784 that, a step-over momentarily stops all threads while LWP is
4785 single-stepped by either hardware or software while the breakpoint
4786 is temporarily uninserted from the inferior. When the single-step
4787 finishes, we reinsert the breakpoint, and let all threads that are
4788 supposed to be running, run again. */
4791 start_step_over (struct lwp_info
*lwp
)
4793 struct thread_info
*thread
= get_lwp_thread (lwp
);
4794 struct thread_info
*saved_thread
;
4799 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4802 stop_all_lwps (1, lwp
);
4804 if (lwp
->suspended
!= 0)
4806 internal_error (__FILE__
, __LINE__
,
4807 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4812 debug_printf ("Done stopping all threads for step-over.\n");
4814 /* Note, we should always reach here with an already adjusted PC,
4815 either by GDB (if we're resuming due to GDB's request), or by our
4816 caller, if we just finished handling an internal breakpoint GDB
4817 shouldn't care about. */
4820 saved_thread
= current_thread
;
4821 current_thread
= thread
;
4823 lwp
->bp_reinsert
= pc
;
4824 uninsert_breakpoints_at (pc
);
4825 uninsert_fast_tracepoint_jumps_at (pc
);
4827 step
= single_step (lwp
);
4829 current_thread
= saved_thread
;
4831 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4833 /* Require next event from this LWP. */
4834 step_over_bkpt
= thread
->id
;
4838 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4839 start_step_over, if still there, and delete any single-step
4840 breakpoints we've set, on non hardware single-step targets. */
4843 finish_step_over (struct lwp_info
*lwp
)
4845 if (lwp
->bp_reinsert
!= 0)
4847 struct thread_info
*saved_thread
= current_thread
;
4850 debug_printf ("Finished step over.\n");
4852 current_thread
= get_lwp_thread (lwp
);
4854 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4855 may be no breakpoint to reinsert there by now. */
4856 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4857 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4859 lwp
->bp_reinsert
= 0;
4861 /* Delete any single-step breakpoints. No longer needed. We
4862 don't have to worry about other threads hitting this trap,
4863 and later not being able to explain it, because we were
4864 stepping over a breakpoint, and we hold all threads but
4865 LWP stopped while doing that. */
4866 if (!can_hardware_single_step ())
4868 gdb_assert (has_single_step_breakpoints (current_thread
));
4869 delete_single_step_breakpoints (current_thread
);
4872 step_over_bkpt
= null_ptid
;
4873 current_thread
= saved_thread
;
4880 /* If there's a step over in progress, wait until all threads stop
4881 (that is, until the stepping thread finishes its step), and
4882 unsuspend all lwps. The stepping thread ends with its status
4883 pending, which is processed later when we get back to processing
4887 complete_ongoing_step_over (void)
4889 if (!ptid_equal (step_over_bkpt
, null_ptid
))
4891 struct lwp_info
*lwp
;
4896 debug_printf ("detach: step over in progress, finish it first\n");
4898 /* Passing NULL_PTID as filter indicates we want all events to
4899 be left pending. Eventually this returns when there are no
4900 unwaited-for children left. */
4901 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4903 gdb_assert (ret
== -1);
4905 lwp
= find_lwp_pid (step_over_bkpt
);
4907 finish_step_over (lwp
);
4908 step_over_bkpt
= null_ptid
;
4909 unsuspend_all_lwps (lwp
);
4913 /* This function is called once per thread. We check the thread's resume
4914 request, which will tell us whether to resume, step, or leave the thread
4915 stopped; and what signal, if any, it should be sent.
4917 For threads which we aren't explicitly told otherwise, we preserve
4918 the stepping flag; this is used for stepping over gdbserver-placed
4921 If pending_flags was set in any thread, we queue any needed
4922 signals, since we won't actually resume. We already have a pending
4923 event to report, so we don't need to preserve any step requests;
4924 they should be re-issued if necessary. */
4927 linux_resume_one_thread (thread_info
*thread
, bool leave_all_stopped
)
4929 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4932 if (lwp
->resume
== NULL
)
4935 if (lwp
->resume
->kind
== resume_stop
)
4938 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4943 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4945 /* Stop the thread, and wait for the event asynchronously,
4946 through the event loop. */
4952 debug_printf ("already stopped LWP %ld\n",
4955 /* The LWP may have been stopped in an internal event that
4956 was not meant to be notified back to GDB (e.g., gdbserver
4957 breakpoint), so we should be reporting a stop event in
4960 /* If the thread already has a pending SIGSTOP, this is a
4961 no-op. Otherwise, something later will presumably resume
4962 the thread and this will cause it to cancel any pending
4963 operation, due to last_resume_kind == resume_stop. If
4964 the thread already has a pending status to report, we
4965 will still report it the next time we wait - see
4966 status_pending_p_callback. */
4968 /* If we already have a pending signal to report, then
4969 there's no need to queue a SIGSTOP, as this means we're
4970 midway through moving the LWP out of the jumppad, and we
4971 will report the pending signal as soon as that is
4973 if (lwp
->pending_signals_to_report
== NULL
)
4977 /* For stop requests, we're done. */
4979 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4983 /* If this thread which is about to be resumed has a pending status,
4984 then don't resume it - we can just report the pending status.
4985 Likewise if it is suspended, because e.g., another thread is
4986 stepping past a breakpoint. Make sure to queue any signals that
4987 would otherwise be sent. In all-stop mode, we do this decision
4988 based on if *any* thread has a pending status. If there's a
4989 thread that needs the step-over-breakpoint dance, then don't
4990 resume any other thread but that particular one. */
4991 leave_pending
= (lwp
->suspended
4992 || lwp
->status_pending_p
4993 || leave_all_stopped
);
4995 /* If we have a new signal, enqueue the signal. */
4996 if (lwp
->resume
->sig
!= 0)
4998 siginfo_t info
, *info_p
;
5000 /* If this is the same signal we were previously stopped by,
5001 make sure to queue its siginfo. */
5002 if (WIFSTOPPED (lwp
->last_status
)
5003 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
5004 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
),
5005 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
5010 enqueue_pending_signal (lwp
, lwp
->resume
->sig
, info_p
);
5016 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
5018 proceed_one_lwp (thread
, NULL
);
5023 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
5026 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
5031 linux_resume (struct thread_resume
*resume_info
, size_t n
)
5033 struct thread_info
*need_step_over
= NULL
;
5038 debug_printf ("linux_resume:\n");
5041 for_each_thread ([&] (thread_info
*thread
)
5043 linux_set_resume_request (thread
, resume_info
, n
);
5046 /* If there is a thread which would otherwise be resumed, which has
5047 a pending status, then don't resume any threads - we can just
5048 report the pending status. Make sure to queue any signals that
5049 would otherwise be sent. In non-stop mode, we'll apply this
5050 logic to each thread individually. We consume all pending events
5051 before considering to start a step-over (in all-stop). */
5052 bool any_pending
= false;
5054 any_pending
= find_thread (resume_status_pending_p
) != NULL
;
5056 /* If there is a thread which would otherwise be resumed, which is
5057 stopped at a breakpoint that needs stepping over, then don't
5058 resume any threads - have it step over the breakpoint with all
5059 other threads stopped, then resume all threads again. Make sure
5060 to queue any signals that would otherwise be delivered or
5062 if (!any_pending
&& supports_breakpoints ())
5063 need_step_over
= find_thread (need_step_over_p
);
5065 bool leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
5069 if (need_step_over
!= NULL
)
5070 debug_printf ("Not resuming all, need step over\n");
5071 else if (any_pending
)
5072 debug_printf ("Not resuming, all-stop and found "
5073 "an LWP with pending status\n");
5075 debug_printf ("Resuming, no pending status or step over needed\n");
5078 /* Even if we're leaving threads stopped, queue all signals we'd
5079 otherwise deliver. */
5080 for_each_thread ([&] (thread_info
*thread
)
5082 linux_resume_one_thread (thread
, leave_all_stopped
);
5086 start_step_over (get_thread_lwp (need_step_over
));
5090 debug_printf ("linux_resume done\n");
5094 /* We may have events that were pending that can/should be sent to
5095 the client now. Trigger a linux_wait call. */
5096 if (target_is_async_p ())
5100 /* This function is called once per thread. We check the thread's
5101 last resume request, which will tell us whether to resume, step, or
5102 leave the thread stopped. Any signal the client requested to be
5103 delivered has already been enqueued at this point.
5105 If any thread that GDB wants running is stopped at an internal
5106 breakpoint that needs stepping over, we start a step-over operation
5107 on that particular thread, and leave all others stopped. */
5110 proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
5112 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5119 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
5124 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
5128 if (thread
->last_resume_kind
== resume_stop
5129 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
5132 debug_printf (" client wants LWP to remain %ld stopped\n",
5137 if (lwp
->status_pending_p
)
5140 debug_printf (" LWP %ld has pending status, leaving stopped\n",
5145 gdb_assert (lwp
->suspended
>= 0);
5150 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
5154 if (thread
->last_resume_kind
== resume_stop
5155 && lwp
->pending_signals_to_report
== NULL
5156 && (lwp
->collecting_fast_tracepoint
5157 == fast_tpoint_collect_result::not_collecting
))
5159 /* We haven't reported this LWP as stopped yet (otherwise, the
5160 last_status.kind check above would catch it, and we wouldn't
5161 reach here. This LWP may have been momentarily paused by a
5162 stop_all_lwps call while handling for example, another LWP's
5163 step-over. In that case, the pending expected SIGSTOP signal
5164 that was queued at vCont;t handling time will have already
5165 been consumed by wait_for_sigstop, and so we need to requeue
5166 another one here. Note that if the LWP already has a SIGSTOP
5167 pending, this is a no-op. */
5170 debug_printf ("Client wants LWP %ld to stop. "
5171 "Making sure it has a SIGSTOP pending\n",
5177 if (thread
->last_resume_kind
== resume_step
)
5180 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5183 /* If resume_step is requested by GDB, install single-step
5184 breakpoints when the thread is about to be actually resumed if
5185 the single-step breakpoints weren't removed. */
5186 if (can_software_single_step ()
5187 && !has_single_step_breakpoints (thread
))
5188 install_software_single_step_breakpoints (lwp
);
5190 step
= maybe_hw_step (thread
);
5192 else if (lwp
->bp_reinsert
!= 0)
5195 debug_printf (" stepping LWP %ld, reinsert set\n",
5198 step
= maybe_hw_step (thread
);
5203 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
5207 unsuspend_and_proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
5209 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5214 lwp_suspended_decr (lwp
);
5216 proceed_one_lwp (thread
, except
);
5219 /* When we finish a step-over, set threads running again. If there's
5220 another thread that may need a step-over, now's the time to start
5221 it. Eventually, we'll move all threads past their breakpoints. */
5224 proceed_all_lwps (void)
5226 struct thread_info
*need_step_over
;
5228 /* If there is a thread which would otherwise be resumed, which is
5229 stopped at a breakpoint that needs stepping over, then don't
5230 resume any threads - have it step over the breakpoint with all
5231 other threads stopped, then resume all threads again. */
5233 if (supports_breakpoints ())
5235 need_step_over
= find_thread (need_step_over_p
);
5237 if (need_step_over
!= NULL
)
5240 debug_printf ("proceed_all_lwps: found "
5241 "thread %ld needing a step-over\n",
5242 lwpid_of (need_step_over
));
5244 start_step_over (get_thread_lwp (need_step_over
));
5250 debug_printf ("Proceeding, no step-over needed\n");
5252 for_each_thread ([] (thread_info
*thread
)
5254 proceed_one_lwp (thread
, NULL
);
5258 /* Stopped LWPs that the client wanted to be running, that don't have
5259 pending statuses, are set to run again, except for EXCEPT, if not
5260 NULL. This undoes a stop_all_lwps call. */
5263 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
5269 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5270 lwpid_of (get_lwp_thread (except
)));
5272 debug_printf ("unstopping all lwps\n");
5276 for_each_thread ([&] (thread_info
*thread
)
5278 unsuspend_and_proceed_one_lwp (thread
, except
);
5281 for_each_thread ([&] (thread_info
*thread
)
5283 proceed_one_lwp (thread
, except
);
5288 debug_printf ("unstop_all_lwps done\n");
5294 #ifdef HAVE_LINUX_REGSETS
5296 #define use_linux_regsets 1
5298 /* Returns true if REGSET has been disabled. */
5301 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5303 return (info
->disabled_regsets
!= NULL
5304 && info
->disabled_regsets
[regset
- info
->regsets
]);
5307 /* Disable REGSET. */
5310 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5314 dr_offset
= regset
- info
->regsets
;
5315 if (info
->disabled_regsets
== NULL
)
5316 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5317 info
->disabled_regsets
[dr_offset
] = 1;
5321 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5322 struct regcache
*regcache
)
5324 struct regset_info
*regset
;
5325 int saw_general_regs
= 0;
5329 pid
= lwpid_of (current_thread
);
5330 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5335 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5338 buf
= xmalloc (regset
->size
);
5340 nt_type
= regset
->nt_type
;
5344 iov
.iov_len
= regset
->size
;
5345 data
= (void *) &iov
;
5351 res
= ptrace (regset
->get_request
, pid
,
5352 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5354 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5360 /* If we get EIO on a regset, do not try it again for
5361 this process mode. */
5362 disable_regset (regsets_info
, regset
);
5364 else if (errno
== ENODATA
)
5366 /* ENODATA may be returned if the regset is currently
5367 not "active". This can happen in normal operation,
5368 so suppress the warning in this case. */
5370 else if (errno
== ESRCH
)
5372 /* At this point, ESRCH should mean the process is
5373 already gone, in which case we simply ignore attempts
5374 to read its registers. */
5379 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5386 if (regset
->type
== GENERAL_REGS
)
5387 saw_general_regs
= 1;
5388 regset
->store_function (regcache
, buf
);
5392 if (saw_general_regs
)
5399 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5400 struct regcache
*regcache
)
5402 struct regset_info
*regset
;
5403 int saw_general_regs
= 0;
5407 pid
= lwpid_of (current_thread
);
5408 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5413 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5414 || regset
->fill_function
== NULL
)
5417 buf
= xmalloc (regset
->size
);
5419 /* First fill the buffer with the current register set contents,
5420 in case there are any items in the kernel's regset that are
5421 not in gdbserver's regcache. */
5423 nt_type
= regset
->nt_type
;
5427 iov
.iov_len
= regset
->size
;
5428 data
= (void *) &iov
;
5434 res
= ptrace (regset
->get_request
, pid
,
5435 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5437 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5442 /* Then overlay our cached registers on that. */
5443 regset
->fill_function (regcache
, buf
);
5445 /* Only now do we write the register set. */
5447 res
= ptrace (regset
->set_request
, pid
,
5448 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5450 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5458 /* If we get EIO on a regset, do not try it again for
5459 this process mode. */
5460 disable_regset (regsets_info
, regset
);
5462 else if (errno
== ESRCH
)
5464 /* At this point, ESRCH should mean the process is
5465 already gone, in which case we simply ignore attempts
5466 to change its registers. See also the related
5467 comment in linux_resume_one_lwp. */
5473 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5476 else if (regset
->type
== GENERAL_REGS
)
5477 saw_general_regs
= 1;
5480 if (saw_general_regs
)
5486 #else /* !HAVE_LINUX_REGSETS */
5488 #define use_linux_regsets 0
5489 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5490 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5494 /* Return 1 if register REGNO is supported by one of the regset ptrace
5495 calls or 0 if it has to be transferred individually. */
5498 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5500 unsigned char mask
= 1 << (regno
% 8);
5501 size_t index
= regno
/ 8;
5503 return (use_linux_regsets
5504 && (regs_info
->regset_bitmap
== NULL
5505 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5508 #ifdef HAVE_LINUX_USRREGS
5511 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5515 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5516 error ("Invalid register number %d.", regnum
);
5518 addr
= usrregs
->regmap
[regnum
];
5523 /* Fetch one register. */
5525 fetch_register (const struct usrregs_info
*usrregs
,
5526 struct regcache
*regcache
, int regno
)
5533 if (regno
>= usrregs
->num_regs
)
5535 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5538 regaddr
= register_addr (usrregs
, regno
);
5542 size
= ((register_size (regcache
->tdesc
, regno
)
5543 + sizeof (PTRACE_XFER_TYPE
) - 1)
5544 & -sizeof (PTRACE_XFER_TYPE
));
5545 buf
= (char *) alloca (size
);
5547 pid
= lwpid_of (current_thread
);
5548 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5551 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5552 ptrace (PTRACE_PEEKUSER
, pid
,
5553 /* Coerce to a uintptr_t first to avoid potential gcc warning
5554 of coercing an 8 byte integer to a 4 byte pointer. */
5555 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5556 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5559 /* Mark register REGNO unavailable. */
5560 supply_register (regcache
, regno
, NULL
);
5565 if (the_low_target
.supply_ptrace_register
)
5566 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5568 supply_register (regcache
, regno
, buf
);
5571 /* Store one register. */
5573 store_register (const struct usrregs_info
*usrregs
,
5574 struct regcache
*regcache
, int regno
)
5581 if (regno
>= usrregs
->num_regs
)
5583 if ((*the_low_target
.cannot_store_register
) (regno
))
5586 regaddr
= register_addr (usrregs
, regno
);
5590 size
= ((register_size (regcache
->tdesc
, regno
)
5591 + sizeof (PTRACE_XFER_TYPE
) - 1)
5592 & -sizeof (PTRACE_XFER_TYPE
));
5593 buf
= (char *) alloca (size
);
5594 memset (buf
, 0, size
);
5596 if (the_low_target
.collect_ptrace_register
)
5597 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5599 collect_register (regcache
, regno
, buf
);
5601 pid
= lwpid_of (current_thread
);
5602 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5605 ptrace (PTRACE_POKEUSER
, pid
,
5606 /* Coerce to a uintptr_t first to avoid potential gcc warning
5607 about coercing an 8 byte integer to a 4 byte pointer. */
5608 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5609 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5612 /* At this point, ESRCH should mean the process is
5613 already gone, in which case we simply ignore attempts
5614 to change its registers. See also the related
5615 comment in linux_resume_one_lwp. */
5619 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5620 error ("writing register %d: %s", regno
, strerror (errno
));
5622 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5626 /* Fetch all registers, or just one, from the child process.
5627 If REGNO is -1, do this for all registers, skipping any that are
5628 assumed to have been retrieved by regsets_fetch_inferior_registers,
5629 unless ALL is non-zero.
5630 Otherwise, REGNO specifies which register (so we can save time). */
5632 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5633 struct regcache
*regcache
, int regno
, int all
)
5635 struct usrregs_info
*usr
= regs_info
->usrregs
;
5639 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5640 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5641 fetch_register (usr
, regcache
, regno
);
5644 fetch_register (usr
, regcache
, regno
);
5647 /* Store our register values back into the inferior.
5648 If REGNO is -1, do this for all registers, skipping any that are
5649 assumed to have been saved by regsets_store_inferior_registers,
5650 unless ALL is non-zero.
5651 Otherwise, REGNO specifies which register (so we can save time). */
5653 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5654 struct regcache
*regcache
, int regno
, int all
)
5656 struct usrregs_info
*usr
= regs_info
->usrregs
;
5660 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5661 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5662 store_register (usr
, regcache
, regno
);
5665 store_register (usr
, regcache
, regno
);
5668 #else /* !HAVE_LINUX_USRREGS */
5670 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5671 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5677 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5681 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5685 if (the_low_target
.fetch_register
!= NULL
5686 && regs_info
->usrregs
!= NULL
)
5687 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5688 (*the_low_target
.fetch_register
) (regcache
, regno
);
5690 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5691 if (regs_info
->usrregs
!= NULL
)
5692 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5696 if (the_low_target
.fetch_register
!= NULL
5697 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5700 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5702 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5704 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5705 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5710 linux_store_registers (struct regcache
*regcache
, int regno
)
5714 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5718 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5720 if (regs_info
->usrregs
!= NULL
)
5721 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5725 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5727 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5729 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5730 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5735 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5736 to debugger memory starting at MYADDR. */
5739 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5741 int pid
= lwpid_of (current_thread
);
5742 PTRACE_XFER_TYPE
*buffer
;
5750 /* Try using /proc. Don't bother for one word. */
5751 if (len
>= 3 * sizeof (long))
5755 /* We could keep this file open and cache it - possibly one per
5756 thread. That requires some juggling, but is even faster. */
5757 sprintf (filename
, "/proc/%d/mem", pid
);
5758 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5762 /* If pread64 is available, use it. It's faster if the kernel
5763 supports it (only one syscall), and it's 64-bit safe even on
5764 32-bit platforms (for instance, SPARC debugging a SPARC64
5767 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5770 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5771 bytes
= read (fd
, myaddr
, len
);
5778 /* Some data was read, we'll try to get the rest with ptrace. */
5788 /* Round starting address down to longword boundary. */
5789 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5790 /* Round ending address up; get number of longwords that makes. */
5791 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5792 / sizeof (PTRACE_XFER_TYPE
));
5793 /* Allocate buffer of that many longwords. */
5794 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5796 /* Read all the longwords */
5798 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5800 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5801 about coercing an 8 byte integer to a 4 byte pointer. */
5802 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5803 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5804 (PTRACE_TYPE_ARG4
) 0);
5810 /* Copy appropriate bytes out of the buffer. */
5813 i
*= sizeof (PTRACE_XFER_TYPE
);
5814 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5816 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5823 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5824 memory at MEMADDR. On failure (cannot write to the inferior)
5825 returns the value of errno. Always succeeds if LEN is zero. */
5828 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5831 /* Round starting address down to longword boundary. */
5832 CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5833 /* Round ending address up; get number of longwords that makes. */
5835 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5836 / sizeof (PTRACE_XFER_TYPE
);
5838 /* Allocate buffer of that many longwords. */
5839 PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5841 int pid
= lwpid_of (current_thread
);
5845 /* Zero length write always succeeds. */
5851 /* Dump up to four bytes. */
5852 char str
[4 * 2 + 1];
5854 int dump
= len
< 4 ? len
: 4;
5856 for (i
= 0; i
< dump
; i
++)
5858 sprintf (p
, "%02x", myaddr
[i
]);
5863 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5864 str
, (long) memaddr
, pid
);
5867 /* Fill start and end extra bytes of buffer with existing memory data. */
5870 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5871 about coercing an 8 byte integer to a 4 byte pointer. */
5872 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5873 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5874 (PTRACE_TYPE_ARG4
) 0);
5882 = ptrace (PTRACE_PEEKTEXT
, pid
,
5883 /* Coerce to a uintptr_t first to avoid potential gcc warning
5884 about coercing an 8 byte integer to a 4 byte pointer. */
5885 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5886 * sizeof (PTRACE_XFER_TYPE
)),
5887 (PTRACE_TYPE_ARG4
) 0);
5892 /* Copy data to be written over corresponding part of buffer. */
5894 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5897 /* Write the entire buffer. */
5899 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5902 ptrace (PTRACE_POKETEXT
, pid
,
5903 /* Coerce to a uintptr_t first to avoid potential gcc warning
5904 about coercing an 8 byte integer to a 4 byte pointer. */
5905 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5906 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5915 linux_look_up_symbols (void)
5917 #ifdef USE_THREAD_DB
5918 struct process_info
*proc
= current_process ();
5920 if (proc
->priv
->thread_db
!= NULL
)
5928 linux_request_interrupt (void)
5930 /* Send a SIGINT to the process group. This acts just like the user
5931 typed a ^C on the controlling terminal. */
5932 kill (-signal_pid
, SIGINT
);
5935 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5936 to debugger memory starting at MYADDR. */
5939 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5941 char filename
[PATH_MAX
];
5943 int pid
= lwpid_of (current_thread
);
5945 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5947 fd
= open (filename
, O_RDONLY
);
5951 if (offset
!= (CORE_ADDR
) 0
5952 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5955 n
= read (fd
, myaddr
, len
);
5962 /* These breakpoint and watchpoint related wrapper functions simply
5963 pass on the function call if the target has registered a
5964 corresponding function. */
5967 linux_supports_z_point_type (char z_type
)
5969 return (the_low_target
.supports_z_point_type
!= NULL
5970 && the_low_target
.supports_z_point_type (z_type
));
5974 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5975 int size
, struct raw_breakpoint
*bp
)
5977 if (type
== raw_bkpt_type_sw
)
5978 return insert_memory_breakpoint (bp
);
5979 else if (the_low_target
.insert_point
!= NULL
)
5980 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5982 /* Unsupported (see target.h). */
5987 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5988 int size
, struct raw_breakpoint
*bp
)
5990 if (type
== raw_bkpt_type_sw
)
5991 return remove_memory_breakpoint (bp
);
5992 else if (the_low_target
.remove_point
!= NULL
)
5993 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5995 /* Unsupported (see target.h). */
5999 /* Implement the to_stopped_by_sw_breakpoint target_ops
6003 linux_stopped_by_sw_breakpoint (void)
6005 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6007 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
6010 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
6014 linux_supports_stopped_by_sw_breakpoint (void)
6016 return USE_SIGTRAP_SIGINFO
;
6019 /* Implement the to_stopped_by_hw_breakpoint target_ops
6023 linux_stopped_by_hw_breakpoint (void)
6025 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6027 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
6030 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
6034 linux_supports_stopped_by_hw_breakpoint (void)
6036 return USE_SIGTRAP_SIGINFO
;
6039 /* Implement the supports_hardware_single_step target_ops method. */
6042 linux_supports_hardware_single_step (void)
6044 return can_hardware_single_step ();
6048 linux_supports_software_single_step (void)
6050 return can_software_single_step ();
6054 linux_stopped_by_watchpoint (void)
6056 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6058 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
6062 linux_stopped_data_address (void)
6064 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6066 return lwp
->stopped_data_address
;
6069 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6070 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6071 && defined(PT_TEXT_END_ADDR)
6073 /* This is only used for targets that define PT_TEXT_ADDR,
6074 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
6075 the target has different ways of acquiring this information, like
6078 /* Under uClinux, programs are loaded at non-zero offsets, which we need
6079 to tell gdb about. */
6082 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
6084 unsigned long text
, text_end
, data
;
6085 int pid
= lwpid_of (current_thread
);
6089 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
6090 (PTRACE_TYPE_ARG4
) 0);
6091 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
6092 (PTRACE_TYPE_ARG4
) 0);
6093 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
6094 (PTRACE_TYPE_ARG4
) 0);
6098 /* Both text and data offsets produced at compile-time (and so
6099 used by gdb) are relative to the beginning of the program,
6100 with the data segment immediately following the text segment.
6101 However, the actual runtime layout in memory may put the data
6102 somewhere else, so when we send gdb a data base-address, we
6103 use the real data base address and subtract the compile-time
6104 data base-address from it (which is just the length of the
6105 text segment). BSS immediately follows data in both
6108 *data_p
= data
- (text_end
- text
);
6117 linux_qxfer_osdata (const char *annex
,
6118 unsigned char *readbuf
, unsigned const char *writebuf
,
6119 CORE_ADDR offset
, int len
)
6121 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
6124 /* Convert a native/host siginfo object, into/from the siginfo in the
6125 layout of the inferiors' architecture. */
6128 siginfo_fixup (siginfo_t
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
6132 if (the_low_target
.siginfo_fixup
!= NULL
)
6133 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
6135 /* If there was no callback, or the callback didn't do anything,
6136 then just do a straight memcpy. */
6140 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
6142 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
6147 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
6148 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
6152 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
6154 if (current_thread
== NULL
)
6157 pid
= lwpid_of (current_thread
);
6160 debug_printf ("%s siginfo for lwp %d.\n",
6161 readbuf
!= NULL
? "Reading" : "Writing",
6164 if (offset
>= sizeof (siginfo
))
6167 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6170 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6171 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6172 inferior with a 64-bit GDBSERVER should look the same as debugging it
6173 with a 32-bit GDBSERVER, we need to convert it. */
6174 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
6176 if (offset
+ len
> sizeof (siginfo
))
6177 len
= sizeof (siginfo
) - offset
;
6179 if (readbuf
!= NULL
)
6180 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6183 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6185 /* Convert back to ptrace layout before flushing it out. */
6186 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6188 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6195 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6196 so we notice when children change state; as the handler for the
6197 sigsuspend in my_waitpid. */
6200 sigchld_handler (int signo
)
6202 int old_errno
= errno
;
6208 /* fprintf is not async-signal-safe, so call write
6210 if (write (2, "sigchld_handler\n",
6211 sizeof ("sigchld_handler\n") - 1) < 0)
6212 break; /* just ignore */
6216 if (target_is_async_p ())
6217 async_file_mark (); /* trigger a linux_wait */
6223 linux_supports_non_stop (void)
6229 linux_async (int enable
)
6231 int previous
= target_is_async_p ();
6234 debug_printf ("linux_async (%d), previous=%d\n",
6237 if (previous
!= enable
)
6240 sigemptyset (&mask
);
6241 sigaddset (&mask
, SIGCHLD
);
6243 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
6247 if (pipe (linux_event_pipe
) == -1)
6249 linux_event_pipe
[0] = -1;
6250 linux_event_pipe
[1] = -1;
6251 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6253 warning ("creating event pipe failed.");
6257 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6258 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6260 /* Register the event loop handler. */
6261 add_file_handler (linux_event_pipe
[0],
6262 handle_target_event
, NULL
);
6264 /* Always trigger a linux_wait. */
6269 delete_file_handler (linux_event_pipe
[0]);
6271 close (linux_event_pipe
[0]);
6272 close (linux_event_pipe
[1]);
6273 linux_event_pipe
[0] = -1;
6274 linux_event_pipe
[1] = -1;
6277 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6284 linux_start_non_stop (int nonstop
)
6286 /* Register or unregister from event-loop accordingly. */
6287 linux_async (nonstop
);
6289 if (target_is_async_p () != (nonstop
!= 0))
6296 linux_supports_multi_process (void)
6301 /* Check if fork events are supported. */
6304 linux_supports_fork_events (void)
6306 return linux_supports_tracefork ();
6309 /* Check if vfork events are supported. */
6312 linux_supports_vfork_events (void)
6314 return linux_supports_tracefork ();
6317 /* Check if exec events are supported. */
6320 linux_supports_exec_events (void)
6322 return linux_supports_traceexec ();
6325 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6326 ptrace flags for all inferiors. This is in case the new GDB connection
6327 doesn't support the same set of events that the previous one did. */
6330 linux_handle_new_gdb_connection (void)
6332 /* Request that all the lwps reset their ptrace options. */
6333 for_each_thread ([] (thread_info
*thread
)
6335 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6339 /* Stop the lwp so we can modify its ptrace options. */
6340 lwp
->must_set_ptrace_flags
= 1;
6341 linux_stop_lwp (lwp
);
6345 /* Already stopped; go ahead and set the ptrace options. */
6346 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6347 int options
= linux_low_ptrace_options (proc
->attached
);
6349 linux_enable_event_reporting (lwpid_of (thread
), options
);
6350 lwp
->must_set_ptrace_flags
= 0;
6356 linux_supports_disable_randomization (void)
6358 #ifdef HAVE_PERSONALITY
6366 linux_supports_agent (void)
6372 linux_supports_range_stepping (void)
6374 if (can_software_single_step ())
6376 if (*the_low_target
.supports_range_stepping
== NULL
)
6379 return (*the_low_target
.supports_range_stepping
) ();
6382 /* Enumerate spufs IDs for process PID. */
6384 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6390 struct dirent
*entry
;
6392 sprintf (path
, "/proc/%ld/fd", pid
);
6393 dir
= opendir (path
);
6398 while ((entry
= readdir (dir
)) != NULL
)
6404 fd
= atoi (entry
->d_name
);
6408 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6409 if (stat (path
, &st
) != 0)
6411 if (!S_ISDIR (st
.st_mode
))
6414 if (statfs (path
, &stfs
) != 0)
6416 if (stfs
.f_type
!= SPUFS_MAGIC
)
6419 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6421 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6431 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6432 object type, using the /proc file system. */
6434 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6435 unsigned const char *writebuf
,
6436 CORE_ADDR offset
, int len
)
6438 long pid
= lwpid_of (current_thread
);
6443 if (!writebuf
&& !readbuf
)
6451 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6454 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6455 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6460 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6467 ret
= write (fd
, writebuf
, (size_t) len
);
6469 ret
= read (fd
, readbuf
, (size_t) len
);
6475 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6476 struct target_loadseg
6478 /* Core address to which the segment is mapped. */
6480 /* VMA recorded in the program header. */
6482 /* Size of this segment in memory. */
6486 # if defined PT_GETDSBT
6487 struct target_loadmap
6489 /* Protocol version number, must be zero. */
6491 /* Pointer to the DSBT table, its size, and the DSBT index. */
6492 unsigned *dsbt_table
;
6493 unsigned dsbt_size
, dsbt_index
;
6494 /* Number of segments in this map. */
6496 /* The actual memory map. */
6497 struct target_loadseg segs
[/*nsegs*/];
6499 # define LINUX_LOADMAP PT_GETDSBT
6500 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6501 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6503 struct target_loadmap
6505 /* Protocol version number, must be zero. */
6507 /* Number of segments in this map. */
6509 /* The actual memory map. */
6510 struct target_loadseg segs
[/*nsegs*/];
6512 # define LINUX_LOADMAP PTRACE_GETFDPIC
6513 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6514 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6518 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6519 unsigned char *myaddr
, unsigned int len
)
6521 int pid
= lwpid_of (current_thread
);
6523 struct target_loadmap
*data
= NULL
;
6524 unsigned int actual_length
, copy_length
;
6526 if (strcmp (annex
, "exec") == 0)
6527 addr
= (int) LINUX_LOADMAP_EXEC
;
6528 else if (strcmp (annex
, "interp") == 0)
6529 addr
= (int) LINUX_LOADMAP_INTERP
;
6533 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6539 actual_length
= sizeof (struct target_loadmap
)
6540 + sizeof (struct target_loadseg
) * data
->nsegs
;
6542 if (offset
< 0 || offset
> actual_length
)
6545 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6546 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6550 # define linux_read_loadmap NULL
6551 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6554 linux_process_qsupported (char **features
, int count
)
6556 if (the_low_target
.process_qsupported
!= NULL
)
6557 the_low_target
.process_qsupported (features
, count
);
6561 linux_supports_catch_syscall (void)
6563 return (the_low_target
.get_syscall_trapinfo
!= NULL
6564 && linux_supports_tracesysgood ());
6568 linux_get_ipa_tdesc_idx (void)
6570 if (the_low_target
.get_ipa_tdesc_idx
== NULL
)
6573 return (*the_low_target
.get_ipa_tdesc_idx
) ();
6577 linux_supports_tracepoints (void)
6579 if (*the_low_target
.supports_tracepoints
== NULL
)
6582 return (*the_low_target
.supports_tracepoints
) ();
6586 linux_read_pc (struct regcache
*regcache
)
6588 if (the_low_target
.get_pc
== NULL
)
6591 return (*the_low_target
.get_pc
) (regcache
);
6595 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6597 gdb_assert (the_low_target
.set_pc
!= NULL
);
6599 (*the_low_target
.set_pc
) (regcache
, pc
);
6603 linux_thread_stopped (struct thread_info
*thread
)
6605 return get_thread_lwp (thread
)->stopped
;
6608 /* This exposes stop-all-threads functionality to other modules. */
6611 linux_pause_all (int freeze
)
6613 stop_all_lwps (freeze
, NULL
);
6616 /* This exposes unstop-all-threads functionality to other gdbserver
6620 linux_unpause_all (int unfreeze
)
6622 unstop_all_lwps (unfreeze
, NULL
);
6626 linux_prepare_to_access_memory (void)
6628 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6631 linux_pause_all (1);
6636 linux_done_accessing_memory (void)
6638 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6641 linux_unpause_all (1);
6645 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6646 CORE_ADDR collector
,
6649 CORE_ADDR
*jump_entry
,
6650 CORE_ADDR
*trampoline
,
6651 ULONGEST
*trampoline_size
,
6652 unsigned char *jjump_pad_insn
,
6653 ULONGEST
*jjump_pad_insn_size
,
6654 CORE_ADDR
*adjusted_insn_addr
,
6655 CORE_ADDR
*adjusted_insn_addr_end
,
6658 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6659 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6660 jump_entry
, trampoline
, trampoline_size
,
6661 jjump_pad_insn
, jjump_pad_insn_size
,
6662 adjusted_insn_addr
, adjusted_insn_addr_end
,
6666 static struct emit_ops
*
6667 linux_emit_ops (void)
6669 if (the_low_target
.emit_ops
!= NULL
)
6670 return (*the_low_target
.emit_ops
) ();
6676 linux_get_min_fast_tracepoint_insn_len (void)
6678 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6681 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6684 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6685 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6687 char filename
[PATH_MAX
];
6689 const int auxv_size
= is_elf64
6690 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6691 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6693 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6695 fd
= open (filename
, O_RDONLY
);
6701 while (read (fd
, buf
, auxv_size
) == auxv_size
6702 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6706 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6708 switch (aux
->a_type
)
6711 *phdr_memaddr
= aux
->a_un
.a_val
;
6714 *num_phdr
= aux
->a_un
.a_val
;
6720 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6722 switch (aux
->a_type
)
6725 *phdr_memaddr
= aux
->a_un
.a_val
;
6728 *num_phdr
= aux
->a_un
.a_val
;
6736 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6738 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6739 "phdr_memaddr = %ld, phdr_num = %d",
6740 (long) *phdr_memaddr
, *num_phdr
);
6747 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6750 get_dynamic (const int pid
, const int is_elf64
)
6752 CORE_ADDR phdr_memaddr
, relocation
;
6754 unsigned char *phdr_buf
;
6755 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6757 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6760 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6761 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6763 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6766 /* Compute relocation: it is expected to be 0 for "regular" executables,
6767 non-zero for PIE ones. */
6769 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6772 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6774 if (p
->p_type
== PT_PHDR
)
6775 relocation
= phdr_memaddr
- p
->p_vaddr
;
6779 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6781 if (p
->p_type
== PT_PHDR
)
6782 relocation
= phdr_memaddr
- p
->p_vaddr
;
6785 if (relocation
== -1)
6787 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6788 any real world executables, including PIE executables, have always
6789 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6790 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6791 or present DT_DEBUG anyway (fpc binaries are statically linked).
6793 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6795 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6800 for (i
= 0; i
< num_phdr
; i
++)
6804 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6806 if (p
->p_type
== PT_DYNAMIC
)
6807 return p
->p_vaddr
+ relocation
;
6811 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6813 if (p
->p_type
== PT_DYNAMIC
)
6814 return p
->p_vaddr
+ relocation
;
6821 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6822 can be 0 if the inferior does not yet have the library list initialized.
6823 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6824 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6827 get_r_debug (const int pid
, const int is_elf64
)
6829 CORE_ADDR dynamic_memaddr
;
6830 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6831 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6834 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6835 if (dynamic_memaddr
== 0)
6838 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6842 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6843 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6847 unsigned char buf
[sizeof (Elf64_Xword
)];
6851 #ifdef DT_MIPS_RLD_MAP
6852 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6854 if (linux_read_memory (dyn
->d_un
.d_val
,
6855 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6860 #endif /* DT_MIPS_RLD_MAP */
6861 #ifdef DT_MIPS_RLD_MAP_REL
6862 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6864 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6865 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6870 #endif /* DT_MIPS_RLD_MAP_REL */
6872 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6873 map
= dyn
->d_un
.d_val
;
6875 if (dyn
->d_tag
== DT_NULL
)
6880 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6881 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6885 unsigned char buf
[sizeof (Elf32_Word
)];
6889 #ifdef DT_MIPS_RLD_MAP
6890 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6892 if (linux_read_memory (dyn
->d_un
.d_val
,
6893 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6898 #endif /* DT_MIPS_RLD_MAP */
6899 #ifdef DT_MIPS_RLD_MAP_REL
6900 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6902 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6903 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6908 #endif /* DT_MIPS_RLD_MAP_REL */
6910 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6911 map
= dyn
->d_un
.d_val
;
6913 if (dyn
->d_tag
== DT_NULL
)
6917 dynamic_memaddr
+= dyn_size
;
6923 /* Read one pointer from MEMADDR in the inferior. */
6926 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6930 /* Go through a union so this works on either big or little endian
6931 hosts, when the inferior's pointer size is smaller than the size
6932 of CORE_ADDR. It is assumed the inferior's endianness is the
6933 same of the superior's. */
6936 CORE_ADDR core_addr
;
6941 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6944 if (ptr_size
== sizeof (CORE_ADDR
))
6945 *ptr
= addr
.core_addr
;
6946 else if (ptr_size
== sizeof (unsigned int))
6949 gdb_assert_not_reached ("unhandled pointer size");
6954 struct link_map_offsets
6956 /* Offset and size of r_debug.r_version. */
6957 int r_version_offset
;
6959 /* Offset and size of r_debug.r_map. */
6962 /* Offset to l_addr field in struct link_map. */
6965 /* Offset to l_name field in struct link_map. */
6968 /* Offset to l_ld field in struct link_map. */
6971 /* Offset to l_next field in struct link_map. */
6974 /* Offset to l_prev field in struct link_map. */
6978 /* Construct qXfer:libraries-svr4:read reply. */
6981 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6982 unsigned const char *writebuf
,
6983 CORE_ADDR offset
, int len
)
6986 unsigned document_len
;
6987 struct process_info_private
*const priv
= current_process ()->priv
;
6988 char filename
[PATH_MAX
];
6991 static const struct link_map_offsets lmo_32bit_offsets
=
6993 0, /* r_version offset. */
6994 4, /* r_debug.r_map offset. */
6995 0, /* l_addr offset in link_map. */
6996 4, /* l_name offset in link_map. */
6997 8, /* l_ld offset in link_map. */
6998 12, /* l_next offset in link_map. */
6999 16 /* l_prev offset in link_map. */
7002 static const struct link_map_offsets lmo_64bit_offsets
=
7004 0, /* r_version offset. */
7005 8, /* r_debug.r_map offset. */
7006 0, /* l_addr offset in link_map. */
7007 8, /* l_name offset in link_map. */
7008 16, /* l_ld offset in link_map. */
7009 24, /* l_next offset in link_map. */
7010 32 /* l_prev offset in link_map. */
7012 const struct link_map_offsets
*lmo
;
7013 unsigned int machine
;
7015 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
7016 int allocated
= 1024;
7018 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
7019 int header_done
= 0;
7021 if (writebuf
!= NULL
)
7023 if (readbuf
== NULL
)
7026 pid
= lwpid_of (current_thread
);
7027 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
7028 is_elf64
= elf_64_file_p (filename
, &machine
);
7029 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
7030 ptr_size
= is_elf64
? 8 : 4;
7032 while (annex
[0] != '\0')
7038 sep
= strchr (annex
, '=');
7043 if (len
== 5 && startswith (annex
, "start"))
7045 else if (len
== 4 && startswith (annex
, "prev"))
7049 annex
= strchr (sep
, ';');
7056 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
7063 if (priv
->r_debug
== 0)
7064 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
7066 /* We failed to find DT_DEBUG. Such situation will not change
7067 for this inferior - do not retry it. Report it to GDB as
7068 E01, see for the reasons at the GDB solib-svr4.c side. */
7069 if (priv
->r_debug
== (CORE_ADDR
) -1)
7072 if (priv
->r_debug
!= 0)
7074 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
7075 (unsigned char *) &r_version
,
7076 sizeof (r_version
)) != 0
7079 warning ("unexpected r_debug version %d", r_version
);
7081 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
7082 &lm_addr
, ptr_size
) != 0)
7084 warning ("unable to read r_map from 0x%lx",
7085 (long) priv
->r_debug
+ lmo
->r_map_offset
);
7090 document
= (char *) xmalloc (allocated
);
7091 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
7092 p
= document
+ strlen (document
);
7095 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
7096 &l_name
, ptr_size
) == 0
7097 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
7098 &l_addr
, ptr_size
) == 0
7099 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
7100 &l_ld
, ptr_size
) == 0
7101 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
7102 &l_prev
, ptr_size
) == 0
7103 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
7104 &l_next
, ptr_size
) == 0)
7106 unsigned char libname
[PATH_MAX
];
7108 if (lm_prev
!= l_prev
)
7110 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
7111 (long) lm_prev
, (long) l_prev
);
7115 /* Ignore the first entry even if it has valid name as the first entry
7116 corresponds to the main executable. The first entry should not be
7117 skipped if the dynamic loader was loaded late by a static executable
7118 (see solib-svr4.c parameter ignore_first). But in such case the main
7119 executable does not have PT_DYNAMIC present and this function already
7120 exited above due to failed get_r_debug. */
7123 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
7128 /* Not checking for error because reading may stop before
7129 we've got PATH_MAX worth of characters. */
7131 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
7132 libname
[sizeof (libname
) - 1] = '\0';
7133 if (libname
[0] != '\0')
7135 /* 6x the size for xml_escape_text below. */
7136 size_t len
= 6 * strlen ((char *) libname
);
7140 /* Terminate `<library-list-svr4'. */
7145 while (allocated
< p
- document
+ len
+ 200)
7147 /* Expand to guarantee sufficient storage. */
7148 uintptr_t document_len
= p
- document
;
7150 document
= (char *) xrealloc (document
, 2 * allocated
);
7152 p
= document
+ document_len
;
7155 std::string name
= xml_escape_text ((char *) libname
);
7156 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
7157 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
7158 name
.c_str (), (unsigned long) lm_addr
,
7159 (unsigned long) l_addr
, (unsigned long) l_ld
);
7169 /* Empty list; terminate `<library-list-svr4'. */
7173 strcpy (p
, "</library-list-svr4>");
7175 document_len
= strlen (document
);
7176 if (offset
< document_len
)
7177 document_len
-= offset
;
7180 if (len
> document_len
)
7183 memcpy (readbuf
, document
+ offset
, len
);
7189 #ifdef HAVE_LINUX_BTRACE
7191 /* See to_disable_btrace target method. */
7194 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
7196 enum btrace_error err
;
7198 err
= linux_disable_btrace (tinfo
);
7199 return (err
== BTRACE_ERR_NONE
? 0 : -1);
7202 /* Encode an Intel Processor Trace configuration. */
7205 linux_low_encode_pt_config (struct buffer
*buffer
,
7206 const struct btrace_data_pt_config
*config
)
7208 buffer_grow_str (buffer
, "<pt-config>\n");
7210 switch (config
->cpu
.vendor
)
7213 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7214 "model=\"%u\" stepping=\"%u\"/>\n",
7215 config
->cpu
.family
, config
->cpu
.model
,
7216 config
->cpu
.stepping
);
7223 buffer_grow_str (buffer
, "</pt-config>\n");
7226 /* Encode a raw buffer. */
7229 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
7235 /* We use hex encoding - see common/rsp-low.h. */
7236 buffer_grow_str (buffer
, "<raw>\n");
7242 elem
[0] = tohex ((*data
>> 4) & 0xf);
7243 elem
[1] = tohex (*data
++ & 0xf);
7245 buffer_grow (buffer
, elem
, 2);
7248 buffer_grow_str (buffer
, "</raw>\n");
7251 /* See to_read_btrace target method. */
7254 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
7255 enum btrace_read_type type
)
7257 struct btrace_data btrace
;
7258 struct btrace_block
*block
;
7259 enum btrace_error err
;
7262 btrace_data_init (&btrace
);
7264 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7265 if (err
!= BTRACE_ERR_NONE
)
7267 if (err
== BTRACE_ERR_OVERFLOW
)
7268 buffer_grow_str0 (buffer
, "E.Overflow.");
7270 buffer_grow_str0 (buffer
, "E.Generic Error.");
7275 switch (btrace
.format
)
7277 case BTRACE_FORMAT_NONE
:
7278 buffer_grow_str0 (buffer
, "E.No Trace.");
7281 case BTRACE_FORMAT_BTS
:
7282 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7283 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7286 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
7288 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7289 paddress (block
->begin
), paddress (block
->end
));
7291 buffer_grow_str0 (buffer
, "</btrace>\n");
7294 case BTRACE_FORMAT_PT
:
7295 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7296 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7297 buffer_grow_str (buffer
, "<pt>\n");
7299 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7301 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7302 btrace
.variant
.pt
.size
);
7304 buffer_grow_str (buffer
, "</pt>\n");
7305 buffer_grow_str0 (buffer
, "</btrace>\n");
7309 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7313 btrace_data_fini (&btrace
);
7317 btrace_data_fini (&btrace
);
7321 /* See to_btrace_conf target method. */
7324 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
7325 struct buffer
*buffer
)
7327 const struct btrace_config
*conf
;
7329 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7330 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7332 conf
= linux_btrace_conf (tinfo
);
7335 switch (conf
->format
)
7337 case BTRACE_FORMAT_NONE
:
7340 case BTRACE_FORMAT_BTS
:
7341 buffer_xml_printf (buffer
, "<bts");
7342 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7343 buffer_xml_printf (buffer
, " />\n");
7346 case BTRACE_FORMAT_PT
:
7347 buffer_xml_printf (buffer
, "<pt");
7348 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7349 buffer_xml_printf (buffer
, "/>\n");
7354 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7357 #endif /* HAVE_LINUX_BTRACE */
7359 /* See nat/linux-nat.h. */
7362 current_lwp_ptid (void)
7364 return ptid_of (current_thread
);
7367 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7370 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7372 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7373 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7375 return default_breakpoint_kind_from_pc (pcptr
);
7378 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7380 static const gdb_byte
*
7381 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7383 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7385 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7388 /* Implementation of the target_ops method
7389 "breakpoint_kind_from_current_state". */
7392 linux_breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
)
7394 if (the_low_target
.breakpoint_kind_from_current_state
!= NULL
)
7395 return (*the_low_target
.breakpoint_kind_from_current_state
) (pcptr
);
7397 return linux_breakpoint_kind_from_pc (pcptr
);
7400 /* Default implementation of linux_target_ops method "set_pc" for
7401 32-bit pc register which is literally named "pc". */
7404 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7406 uint32_t newpc
= pc
;
7408 supply_register_by_name (regcache
, "pc", &newpc
);
7411 /* Default implementation of linux_target_ops method "get_pc" for
7412 32-bit pc register which is literally named "pc". */
7415 linux_get_pc_32bit (struct regcache
*regcache
)
7419 collect_register_by_name (regcache
, "pc", &pc
);
7421 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7425 /* Default implementation of linux_target_ops method "set_pc" for
7426 64-bit pc register which is literally named "pc". */
7429 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7431 uint64_t newpc
= pc
;
7433 supply_register_by_name (regcache
, "pc", &newpc
);
7436 /* Default implementation of linux_target_ops method "get_pc" for
7437 64-bit pc register which is literally named "pc". */
7440 linux_get_pc_64bit (struct regcache
*regcache
)
7444 collect_register_by_name (regcache
, "pc", &pc
);
7446 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7451 static struct target_ops linux_target_ops
= {
7452 linux_create_inferior
,
7453 linux_post_create_inferior
,
7462 linux_fetch_registers
,
7463 linux_store_registers
,
7464 linux_prepare_to_access_memory
,
7465 linux_done_accessing_memory
,
7468 linux_look_up_symbols
,
7469 linux_request_interrupt
,
7471 linux_supports_z_point_type
,
7474 linux_stopped_by_sw_breakpoint
,
7475 linux_supports_stopped_by_sw_breakpoint
,
7476 linux_stopped_by_hw_breakpoint
,
7477 linux_supports_stopped_by_hw_breakpoint
,
7478 linux_supports_hardware_single_step
,
7479 linux_stopped_by_watchpoint
,
7480 linux_stopped_data_address
,
7481 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7482 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7483 && defined(PT_TEXT_END_ADDR)
7488 #ifdef USE_THREAD_DB
7489 thread_db_get_tls_address
,
7494 hostio_last_error_from_errno
,
7497 linux_supports_non_stop
,
7499 linux_start_non_stop
,
7500 linux_supports_multi_process
,
7501 linux_supports_fork_events
,
7502 linux_supports_vfork_events
,
7503 linux_supports_exec_events
,
7504 linux_handle_new_gdb_connection
,
7505 #ifdef USE_THREAD_DB
7506 thread_db_handle_monitor_command
,
7510 linux_common_core_of_thread
,
7512 linux_process_qsupported
,
7513 linux_supports_tracepoints
,
7516 linux_thread_stopped
,
7520 linux_stabilize_threads
,
7521 linux_install_fast_tracepoint_jump_pad
,
7523 linux_supports_disable_randomization
,
7524 linux_get_min_fast_tracepoint_insn_len
,
7525 linux_qxfer_libraries_svr4
,
7526 linux_supports_agent
,
7527 #ifdef HAVE_LINUX_BTRACE
7528 linux_supports_btrace
,
7529 linux_enable_btrace
,
7530 linux_low_disable_btrace
,
7531 linux_low_read_btrace
,
7532 linux_low_btrace_conf
,
7540 linux_supports_range_stepping
,
7541 linux_proc_pid_to_exec_file
,
7542 linux_mntns_open_cloexec
,
7544 linux_mntns_readlink
,
7545 linux_breakpoint_kind_from_pc
,
7546 linux_sw_breakpoint_from_kind
,
7547 linux_proc_tid_get_name
,
7548 linux_breakpoint_kind_from_current_state
,
7549 linux_supports_software_single_step
,
7550 linux_supports_catch_syscall
,
7551 linux_get_ipa_tdesc_idx
,
7553 thread_db_thread_handle
,
7559 #ifdef HAVE_LINUX_REGSETS
7561 initialize_regsets_info (struct regsets_info
*info
)
7563 for (info
->num_regsets
= 0;
7564 info
->regsets
[info
->num_regsets
].size
>= 0;
7565 info
->num_regsets
++)
7571 initialize_low (void)
7573 struct sigaction sigchld_action
;
7575 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7576 set_target_ops (&linux_target_ops
);
7578 linux_ptrace_init_warnings ();
7580 sigchld_action
.sa_handler
= sigchld_handler
;
7581 sigemptyset (&sigchld_action
.sa_mask
);
7582 sigchld_action
.sa_flags
= SA_RESTART
;
7583 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7585 initialize_low_arch ();
7587 linux_check_ptrace_features ();