1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2022 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"
22 #include "gdbsupport/agent.h"
24 #include "gdbsupport/rsp-low.h"
25 #include "gdbsupport/signals-state-save-restore.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
28 #include "gdbsupport/gdb_wait.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 "gdbsupport/filestuff.h"
47 #include "tracepoint.h"
49 #include "gdbsupport/common-inferior.h"
50 #include "nat/fork-inferior.h"
51 #include "gdbsupport/environ.h"
52 #include "gdbsupport/gdb-sigmask.h"
53 #include "gdbsupport/scoped_restore.h"
55 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
56 then ELFMAG0 will have been defined. If it didn't get included by
57 gdb_proc_service.h then including it will likely introduce a duplicate
58 definition of elf_fpregset_t. */
61 #include "nat/linux-namespaces.h"
71 /* Some targets did not define these ptrace constants from the start,
72 so gdbserver defines them locally here. In the future, these may
73 be removed after they are added to asm/ptrace.h. */
74 #if !(defined(PT_TEXT_ADDR) \
75 || defined(PT_DATA_ADDR) \
76 || defined(PT_TEXT_END_ADDR))
77 #if defined(__mcoldfire__)
78 /* These are still undefined in 3.10 kernels. */
79 #define PT_TEXT_ADDR 49*4
80 #define PT_DATA_ADDR 50*4
81 #define PT_TEXT_END_ADDR 51*4
82 /* These are still undefined in 3.10 kernels. */
83 #elif defined(__TMS320C6X__)
84 #define PT_TEXT_ADDR (0x10000*4)
85 #define PT_DATA_ADDR (0x10004*4)
86 #define PT_TEXT_END_ADDR (0x10008*4)
90 #if (defined(__UCLIBC__) \
91 && defined(HAS_NOMMU) \
92 && defined(PT_TEXT_ADDR) \
93 && defined(PT_DATA_ADDR) \
94 && defined(PT_TEXT_END_ADDR))
95 #define SUPPORTS_READ_OFFSETS
98 #ifdef HAVE_LINUX_BTRACE
99 # include "nat/linux-btrace.h"
100 # include "gdbsupport/btrace-common.h"
103 #ifndef HAVE_ELF32_AUXV_T
104 /* Copied from glibc's elf.h. */
107 uint32_t a_type
; /* Entry type */
110 uint32_t a_val
; /* Integer value */
111 /* We use to have pointer elements added here. We cannot do that,
112 though, since it does not work when using 32-bit definitions
113 on 64-bit platforms and vice versa. */
118 #ifndef HAVE_ELF64_AUXV_T
119 /* Copied from glibc's elf.h. */
122 uint64_t a_type
; /* Entry type */
125 uint64_t a_val
; /* Integer value */
126 /* We use to have pointer elements added here. We cannot do that,
127 though, since it does not work when using 32-bit definitions
128 on 64-bit platforms and vice versa. */
133 /* Does the current host support PTRACE_GETREGSET? */
134 int have_ptrace_getregset
= -1;
138 /* See nat/linux-nat.h. */
141 ptid_of_lwp (struct lwp_info
*lwp
)
143 return ptid_of (get_lwp_thread (lwp
));
146 /* See nat/linux-nat.h. */
149 lwp_set_arch_private_info (struct lwp_info
*lwp
,
150 struct arch_lwp_info
*info
)
152 lwp
->arch_private
= info
;
155 /* See nat/linux-nat.h. */
157 struct arch_lwp_info
*
158 lwp_arch_private_info (struct lwp_info
*lwp
)
160 return lwp
->arch_private
;
163 /* See nat/linux-nat.h. */
166 lwp_is_stopped (struct lwp_info
*lwp
)
171 /* See nat/linux-nat.h. */
173 enum target_stop_reason
174 lwp_stop_reason (struct lwp_info
*lwp
)
176 return lwp
->stop_reason
;
179 /* See nat/linux-nat.h. */
182 lwp_is_stepping (struct lwp_info
*lwp
)
184 return lwp
->stepping
;
187 /* A list of all unknown processes which receive stop signals. Some
188 other process will presumably claim each of these as forked
189 children momentarily. */
191 struct simple_pid_list
193 /* The process ID. */
196 /* The status as reported by waitpid. */
200 struct simple_pid_list
*next
;
202 static struct simple_pid_list
*stopped_pids
;
204 /* Trivial list manipulation functions to keep track of a list of new
205 stopped processes. */
208 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
210 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
213 new_pid
->status
= status
;
214 new_pid
->next
= *listp
;
219 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
221 struct simple_pid_list
**p
;
223 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
224 if ((*p
)->pid
== pid
)
226 struct simple_pid_list
*next
= (*p
)->next
;
228 *statusp
= (*p
)->status
;
236 enum stopping_threads_kind
238 /* Not stopping threads presently. */
239 NOT_STOPPING_THREADS
,
241 /* Stopping threads. */
244 /* Stopping and suspending threads. */
245 STOPPING_AND_SUSPENDING_THREADS
248 /* This is set while stop_all_lwps is in effect. */
249 static stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
251 /* FIXME make into a target method? */
252 int using_threads
= 1;
254 /* True if we're presently stabilizing threads (moving them out of
256 static int stabilizing_threads
;
258 static void unsuspend_all_lwps (struct lwp_info
*except
);
259 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
260 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
261 static int kill_lwp (unsigned long lwpid
, int signo
);
262 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
263 static int linux_low_ptrace_options (int attached
);
264 static int check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
);
266 /* When the event-loop is doing a step-over, this points at the thread
268 static ptid_t step_over_bkpt
;
271 linux_process_target::low_supports_breakpoints ()
277 linux_process_target::low_get_pc (regcache
*regcache
)
283 linux_process_target::low_set_pc (regcache
*regcache
, CORE_ADDR newpc
)
285 gdb_assert_not_reached ("linux target op low_set_pc is not implemented");
288 std::vector
<CORE_ADDR
>
289 linux_process_target::low_get_next_pcs (regcache
*regcache
)
291 gdb_assert_not_reached ("linux target op low_get_next_pcs is not "
296 linux_process_target::low_decr_pc_after_break ()
301 /* True if LWP is stopped in its stepping range. */
304 lwp_in_step_range (struct lwp_info
*lwp
)
306 CORE_ADDR pc
= lwp
->stop_pc
;
308 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
311 /* The read/write ends of the pipe registered as waitable file in the
313 static int linux_event_pipe
[2] = { -1, -1 };
315 /* True if we're currently in async mode. */
316 #define target_is_async_p() (linux_event_pipe[0] != -1)
318 static void send_sigstop (struct lwp_info
*lwp
);
320 /* Return non-zero if HEADER is a 64-bit ELF file. */
323 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
325 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
326 && header
->e_ident
[EI_MAG1
] == ELFMAG1
327 && header
->e_ident
[EI_MAG2
] == ELFMAG2
328 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
330 *machine
= header
->e_machine
;
331 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
338 /* Return non-zero if FILE is a 64-bit ELF file,
339 zero if the file is not a 64-bit ELF file,
340 and -1 if the file is not accessible or doesn't exist. */
343 elf_64_file_p (const char *file
, unsigned int *machine
)
348 fd
= open (file
, O_RDONLY
);
352 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
359 return elf_64_header_p (&header
, machine
);
362 /* Accepts an integer PID; Returns true if the executable PID is
363 running is a 64-bit ELF file.. */
366 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
370 sprintf (file
, "/proc/%d/exe", pid
);
371 return elf_64_file_p (file
, machine
);
375 linux_process_target::delete_lwp (lwp_info
*lwp
)
377 struct thread_info
*thr
= get_lwp_thread (lwp
);
379 threads_debug_printf ("deleting %ld", lwpid_of (thr
));
383 low_delete_thread (lwp
->arch_private
);
389 linux_process_target::low_delete_thread (arch_lwp_info
*info
)
391 /* Default implementation should be overridden if architecture-specific
392 info is being used. */
393 gdb_assert (info
== nullptr);
397 linux_process_target::add_linux_process (int pid
, int attached
)
399 struct process_info
*proc
;
401 proc
= add_process (pid
, attached
);
402 proc
->priv
= XCNEW (struct process_info_private
);
404 proc
->priv
->arch_private
= low_new_process ();
410 linux_process_target::low_new_process ()
416 linux_process_target::low_delete_process (arch_process_info
*info
)
418 /* Default implementation must be overridden if architecture-specific
420 gdb_assert (info
== nullptr);
424 linux_process_target::low_new_fork (process_info
*parent
, process_info
*child
)
430 linux_process_target::arch_setup_thread (thread_info
*thread
)
432 scoped_restore_current_thread restore_thread
;
433 switch_to_thread (thread
);
439 linux_process_target::handle_extended_wait (lwp_info
**orig_event_lwp
,
442 client_state
&cs
= get_client_state ();
443 struct lwp_info
*event_lwp
= *orig_event_lwp
;
444 int event
= linux_ptrace_get_extended_event (wstat
);
445 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
446 struct lwp_info
*new_lwp
;
448 gdb_assert (event_lwp
->waitstatus
.kind () == TARGET_WAITKIND_IGNORE
);
450 /* All extended events we currently use are mid-syscall. Only
451 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
452 you have to be using PTRACE_SEIZE to get that. */
453 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
455 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
456 || (event
== PTRACE_EVENT_CLONE
))
459 unsigned long new_pid
;
462 /* Get the pid of the new lwp. */
463 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
466 /* If we haven't already seen the new PID stop, wait for it now. */
467 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
469 /* The new child has a pending SIGSTOP. We can't affect it until it
470 hits the SIGSTOP, but we're already attached. */
472 ret
= my_waitpid (new_pid
, &status
, __WALL
);
475 perror_with_name ("waiting for new child");
476 else if (ret
!= new_pid
)
477 warning ("wait returned unexpected PID %d", ret
);
478 else if (!WIFSTOPPED (status
))
479 warning ("wait returned unexpected status 0x%x", status
);
482 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
484 struct process_info
*parent_proc
;
485 struct process_info
*child_proc
;
486 struct lwp_info
*child_lwp
;
487 struct thread_info
*child_thr
;
489 ptid
= ptid_t (new_pid
, new_pid
);
491 threads_debug_printf ("Got fork event from LWP %ld, "
493 ptid_of (event_thr
).lwp (),
496 /* Add the new process to the tables and clone the breakpoint
497 lists of the parent. We need to do this even if the new process
498 will be detached, since we will need the process object and the
499 breakpoints to remove any breakpoints from memory when we
500 detach, and the client side will access registers. */
501 child_proc
= add_linux_process (new_pid
, 0);
502 gdb_assert (child_proc
!= NULL
);
503 child_lwp
= add_lwp (ptid
);
504 gdb_assert (child_lwp
!= NULL
);
505 child_lwp
->stopped
= 1;
506 child_lwp
->must_set_ptrace_flags
= 1;
507 child_lwp
->status_pending_p
= 0;
508 child_thr
= get_lwp_thread (child_lwp
);
509 child_thr
->last_resume_kind
= resume_stop
;
510 child_thr
->last_status
.set_stopped (GDB_SIGNAL_0
);
512 /* If we're suspending all threads, leave this one suspended
513 too. If the fork/clone parent is stepping over a breakpoint,
514 all other threads have been suspended already. Leave the
515 child suspended too. */
516 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
517 || event_lwp
->bp_reinsert
!= 0)
519 threads_debug_printf ("leaving child suspended");
520 child_lwp
->suspended
= 1;
523 parent_proc
= get_thread_process (event_thr
);
524 child_proc
->attached
= parent_proc
->attached
;
526 if (event_lwp
->bp_reinsert
!= 0
527 && supports_software_single_step ()
528 && event
== PTRACE_EVENT_VFORK
)
530 /* If we leave single-step breakpoints there, child will
531 hit it, so uninsert single-step breakpoints from parent
532 (and child). Once vfork child is done, reinsert
533 them back to parent. */
534 uninsert_single_step_breakpoints (event_thr
);
537 clone_all_breakpoints (child_thr
, event_thr
);
539 target_desc_up tdesc
= allocate_target_description ();
540 copy_target_description (tdesc
.get (), parent_proc
->tdesc
);
541 child_proc
->tdesc
= tdesc
.release ();
543 /* Clone arch-specific process data. */
544 low_new_fork (parent_proc
, child_proc
);
546 /* Save fork info in the parent thread. */
547 if (event
== PTRACE_EVENT_FORK
)
548 event_lwp
->waitstatus
.set_forked (ptid
);
549 else if (event
== PTRACE_EVENT_VFORK
)
550 event_lwp
->waitstatus
.set_vforked (ptid
);
552 /* The status_pending field contains bits denoting the
553 extended event, so when the pending event is handled,
554 the handler will look at lwp->waitstatus. */
555 event_lwp
->status_pending_p
= 1;
556 event_lwp
->status_pending
= wstat
;
558 /* Link the threads until the parent event is passed on to
560 event_lwp
->fork_relative
= child_lwp
;
561 child_lwp
->fork_relative
= event_lwp
;
563 /* If the parent thread is doing step-over with single-step
564 breakpoints, the list of single-step breakpoints are cloned
565 from the parent's. Remove them from the child process.
566 In case of vfork, we'll reinsert them back once vforked
568 if (event_lwp
->bp_reinsert
!= 0
569 && supports_software_single_step ())
571 /* The child process is forked and stopped, so it is safe
572 to access its memory without stopping all other threads
573 from other processes. */
574 delete_single_step_breakpoints (child_thr
);
576 gdb_assert (has_single_step_breakpoints (event_thr
));
577 gdb_assert (!has_single_step_breakpoints (child_thr
));
580 /* Report the event. */
585 ("Got clone event from LWP %ld, new child is LWP %ld",
586 lwpid_of (event_thr
), new_pid
);
588 ptid
= ptid_t (pid_of (event_thr
), new_pid
);
589 new_lwp
= add_lwp (ptid
);
591 /* Either we're going to immediately resume the new thread
592 or leave it stopped. resume_one_lwp is a nop if it
593 thinks the thread is currently running, so set this first
594 before calling resume_one_lwp. */
595 new_lwp
->stopped
= 1;
597 /* If we're suspending all threads, leave this one suspended
598 too. If the fork/clone parent is stepping over a breakpoint,
599 all other threads have been suspended already. Leave the
600 child suspended too. */
601 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
602 || event_lwp
->bp_reinsert
!= 0)
603 new_lwp
->suspended
= 1;
605 /* Normally we will get the pending SIGSTOP. But in some cases
606 we might get another signal delivered to the group first.
607 If we do get another signal, be sure not to lose it. */
608 if (WSTOPSIG (status
) != SIGSTOP
)
610 new_lwp
->stop_expected
= 1;
611 new_lwp
->status_pending_p
= 1;
612 new_lwp
->status_pending
= status
;
614 else if (cs
.report_thread_events
)
616 new_lwp
->waitstatus
.set_thread_created ();
617 new_lwp
->status_pending_p
= 1;
618 new_lwp
->status_pending
= status
;
622 thread_db_notice_clone (event_thr
, ptid
);
625 /* Don't report the event. */
628 else if (event
== PTRACE_EVENT_VFORK_DONE
)
630 event_lwp
->waitstatus
.set_vfork_done ();
632 if (event_lwp
->bp_reinsert
!= 0 && supports_software_single_step ())
634 reinsert_single_step_breakpoints (event_thr
);
636 gdb_assert (has_single_step_breakpoints (event_thr
));
639 /* Report the event. */
642 else if (event
== PTRACE_EVENT_EXEC
&& cs
.report_exec_events
)
644 struct process_info
*proc
;
645 std::vector
<int> syscalls_to_catch
;
649 threads_debug_printf ("Got exec event from LWP %ld",
650 lwpid_of (event_thr
));
652 /* Get the event ptid. */
653 event_ptid
= ptid_of (event_thr
);
654 event_pid
= event_ptid
.pid ();
656 /* Save the syscall list from the execing process. */
657 proc
= get_thread_process (event_thr
);
658 syscalls_to_catch
= std::move (proc
->syscalls_to_catch
);
660 /* Delete the execing process and all its threads. */
662 switch_to_thread (nullptr);
664 /* Create a new process/lwp/thread. */
665 proc
= add_linux_process (event_pid
, 0);
666 event_lwp
= add_lwp (event_ptid
);
667 event_thr
= get_lwp_thread (event_lwp
);
668 gdb_assert (current_thread
== event_thr
);
669 arch_setup_thread (event_thr
);
671 /* Set the event status. */
672 event_lwp
->waitstatus
.set_execd
674 (linux_proc_pid_to_exec_file (lwpid_of (event_thr
))));
676 /* Mark the exec status as pending. */
677 event_lwp
->stopped
= 1;
678 event_lwp
->status_pending_p
= 1;
679 event_lwp
->status_pending
= wstat
;
680 event_thr
->last_resume_kind
= resume_continue
;
681 event_thr
->last_status
.set_ignore ();
683 /* Update syscall state in the new lwp, effectively mid-syscall too. */
684 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
686 /* Restore the list to catch. Don't rely on the client, which is free
687 to avoid sending a new list when the architecture doesn't change.
688 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
689 proc
->syscalls_to_catch
= std::move (syscalls_to_catch
);
691 /* Report the event. */
692 *orig_event_lwp
= event_lwp
;
696 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
700 linux_process_target::get_pc (lwp_info
*lwp
)
702 struct regcache
*regcache
;
705 if (!low_supports_breakpoints ())
708 scoped_restore_current_thread restore_thread
;
709 switch_to_thread (get_lwp_thread (lwp
));
711 regcache
= get_thread_regcache (current_thread
, 1);
712 pc
= low_get_pc (regcache
);
714 threads_debug_printf ("pc is 0x%lx", (long) pc
);
720 linux_process_target::get_syscall_trapinfo (lwp_info
*lwp
, int *sysno
)
722 struct regcache
*regcache
;
724 scoped_restore_current_thread restore_thread
;
725 switch_to_thread (get_lwp_thread (lwp
));
727 regcache
= get_thread_regcache (current_thread
, 1);
728 low_get_syscall_trapinfo (regcache
, sysno
);
730 threads_debug_printf ("get_syscall_trapinfo sysno %d", *sysno
);
734 linux_process_target::low_get_syscall_trapinfo (regcache
*regcache
, int *sysno
)
736 /* By default, report an unknown system call number. */
737 *sysno
= UNKNOWN_SYSCALL
;
741 linux_process_target::save_stop_reason (lwp_info
*lwp
)
744 CORE_ADDR sw_breakpoint_pc
;
745 #if USE_SIGTRAP_SIGINFO
749 if (!low_supports_breakpoints ())
753 sw_breakpoint_pc
= pc
- low_decr_pc_after_break ();
755 /* breakpoint_at reads from the current thread. */
756 scoped_restore_current_thread restore_thread
;
757 switch_to_thread (get_lwp_thread (lwp
));
759 #if USE_SIGTRAP_SIGINFO
760 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
761 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
763 if (siginfo
.si_signo
== SIGTRAP
)
765 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
766 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
768 /* The si_code is ambiguous on this arch -- check debug
770 if (!check_stopped_by_watchpoint (lwp
))
771 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
773 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
775 /* If we determine the LWP stopped for a SW breakpoint,
776 trust it. Particularly don't check watchpoint
777 registers, because at least on s390, we'd find
778 stopped-by-watchpoint as long as there's a watchpoint
780 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
782 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
784 /* This can indicate either a hardware breakpoint or
785 hardware watchpoint. Check debug registers. */
786 if (!check_stopped_by_watchpoint (lwp
))
787 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
789 else if (siginfo
.si_code
== TRAP_TRACE
)
791 /* We may have single stepped an instruction that
792 triggered a watchpoint. In that case, on some
793 architectures (such as x86), instead of TRAP_HWBKPT,
794 si_code indicates TRAP_TRACE, and we need to check
795 the debug registers separately. */
796 if (!check_stopped_by_watchpoint (lwp
))
797 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
802 /* We may have just stepped a breakpoint instruction. E.g., in
803 non-stop mode, GDB first tells the thread A to step a range, and
804 then the user inserts a breakpoint inside the range. In that
805 case we need to report the breakpoint PC. */
806 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
807 && low_breakpoint_at (sw_breakpoint_pc
))
808 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
810 if (hardware_breakpoint_inserted_here (pc
))
811 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
813 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
814 check_stopped_by_watchpoint (lwp
);
817 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
820 ("%s stopped by software breakpoint",
821 target_pid_to_str (ptid_of (get_lwp_thread (lwp
))).c_str ());
823 /* Back up the PC if necessary. */
824 if (pc
!= sw_breakpoint_pc
)
826 struct regcache
*regcache
827 = get_thread_regcache (current_thread
, 1);
828 low_set_pc (regcache
, sw_breakpoint_pc
);
831 /* Update this so we record the correct stop PC below. */
832 pc
= sw_breakpoint_pc
;
834 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
836 ("%s stopped by hardware breakpoint",
837 target_pid_to_str (ptid_of (get_lwp_thread (lwp
))).c_str ());
838 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
840 ("%s stopped by hardware watchpoint",
841 target_pid_to_str (ptid_of (get_lwp_thread (lwp
))).c_str ());
842 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
844 ("%s stopped by trace",
845 target_pid_to_str (ptid_of (get_lwp_thread (lwp
))).c_str ());
852 linux_process_target::add_lwp (ptid_t ptid
)
854 lwp_info
*lwp
= new lwp_info
;
856 lwp
->thread
= add_thread (ptid
, lwp
);
858 low_new_thread (lwp
);
864 linux_process_target::low_new_thread (lwp_info
*info
)
869 /* Callback to be used when calling fork_inferior, responsible for
870 actually initiating the tracing of the inferior. */
875 if (ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0,
876 (PTRACE_TYPE_ARG4
) 0) < 0)
877 trace_start_error_with_name ("ptrace");
879 if (setpgid (0, 0) < 0)
880 trace_start_error_with_name ("setpgid");
882 /* If GDBserver is connected to gdb via stdio, redirect the inferior's
883 stdout to stderr so that inferior i/o doesn't corrupt the connection.
884 Also, redirect stdin to /dev/null. */
885 if (remote_connection_is_stdio ())
888 trace_start_error_with_name ("close");
889 if (open ("/dev/null", O_RDONLY
) < 0)
890 trace_start_error_with_name ("open");
892 trace_start_error_with_name ("dup2");
893 if (write (2, "stdin/stdout redirected\n",
894 sizeof ("stdin/stdout redirected\n") - 1) < 0)
896 /* Errors ignored. */;
901 /* Start an inferior process and returns its pid.
902 PROGRAM is the name of the program to be started, and PROGRAM_ARGS
903 are its arguments. */
906 linux_process_target::create_inferior (const char *program
,
907 const std::vector
<char *> &program_args
)
909 client_state
&cs
= get_client_state ();
910 struct lwp_info
*new_lwp
;
915 maybe_disable_address_space_randomization restore_personality
916 (cs
.disable_randomization
);
917 std::string str_program_args
= construct_inferior_arguments (program_args
);
919 pid
= fork_inferior (program
,
920 str_program_args
.c_str (),
921 get_environ ()->envp (), linux_ptrace_fun
,
922 NULL
, NULL
, NULL
, NULL
);
925 add_linux_process (pid
, 0);
927 ptid
= ptid_t (pid
, pid
);
928 new_lwp
= add_lwp (ptid
);
929 new_lwp
->must_set_ptrace_flags
= 1;
931 post_fork_inferior (pid
, program
);
936 /* Implement the post_create_inferior target_ops method. */
939 linux_process_target::post_create_inferior ()
941 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
945 if (lwp
->must_set_ptrace_flags
)
947 struct process_info
*proc
= current_process ();
948 int options
= linux_low_ptrace_options (proc
->attached
);
950 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
951 lwp
->must_set_ptrace_flags
= 0;
956 linux_process_target::attach_lwp (ptid_t ptid
)
958 struct lwp_info
*new_lwp
;
959 int lwpid
= ptid
.lwp ();
961 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
965 new_lwp
= add_lwp (ptid
);
967 /* We need to wait for SIGSTOP before being able to make the next
968 ptrace call on this LWP. */
969 new_lwp
->must_set_ptrace_flags
= 1;
971 if (linux_proc_pid_is_stopped (lwpid
))
973 threads_debug_printf ("Attached to a stopped process");
975 /* The process is definitely stopped. It is in a job control
976 stop, unless the kernel predates the TASK_STOPPED /
977 TASK_TRACED distinction, in which case it might be in a
978 ptrace stop. Make sure it is in a ptrace stop; from there we
979 can kill it, signal it, et cetera.
981 First make sure there is a pending SIGSTOP. Since we are
982 already attached, the process can not transition from stopped
983 to running without a PTRACE_CONT; so we know this signal will
984 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
985 probably already in the queue (unless this kernel is old
986 enough to use TASK_STOPPED for ptrace stops); but since
987 SIGSTOP is not an RT signal, it can only be queued once. */
988 kill_lwp (lwpid
, SIGSTOP
);
990 /* Finally, resume the stopped process. This will deliver the
991 SIGSTOP (or a higher priority signal, just like normal
992 PTRACE_ATTACH), which we'll catch later on. */
993 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
996 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
999 There are several cases to consider here:
1001 1) gdbserver has already attached to the process and is being notified
1002 of a new thread that is being created.
1003 In this case we should ignore that SIGSTOP and resume the
1004 process. This is handled below by setting stop_expected = 1,
1005 and the fact that add_thread sets last_resume_kind ==
1008 2) This is the first thread (the process thread), and we're attaching
1009 to it via attach_inferior.
1010 In this case we want the process thread to stop.
1011 This is handled by having linux_attach set last_resume_kind ==
1012 resume_stop after we return.
1014 If the pid we are attaching to is also the tgid, we attach to and
1015 stop all the existing threads. Otherwise, we attach to pid and
1016 ignore any other threads in the same group as this pid.
1018 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1020 In this case we want the thread to stop.
1021 FIXME: This case is currently not properly handled.
1022 We should wait for the SIGSTOP but don't. Things work apparently
1023 because enough time passes between when we ptrace (ATTACH) and when
1024 gdb makes the next ptrace call on the thread.
1026 On the other hand, if we are currently trying to stop all threads, we
1027 should treat the new thread as if we had sent it a SIGSTOP. This works
1028 because we are guaranteed that the add_lwp call above added us to the
1029 end of the list, and so the new thread has not yet reached
1030 wait_for_sigstop (but will). */
1031 new_lwp
->stop_expected
= 1;
1036 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1037 already attached. Returns true if a new LWP is found, false
1041 attach_proc_task_lwp_callback (ptid_t ptid
)
1043 /* Is this a new thread? */
1044 if (find_thread_ptid (ptid
) == NULL
)
1046 int lwpid
= ptid
.lwp ();
1049 threads_debug_printf ("Found new lwp %d", lwpid
);
1051 err
= the_linux_target
->attach_lwp (ptid
);
1053 /* Be quiet if we simply raced with the thread exiting. EPERM
1054 is returned if the thread's task still exists, and is marked
1055 as exited or zombie, as well as other conditions, so in that
1056 case, confirm the status in /proc/PID/status. */
1058 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1059 threads_debug_printf
1060 ("Cannot attach to lwp %d: thread is gone (%d: %s)",
1061 lwpid
, err
, safe_strerror (err
));
1065 = linux_ptrace_attach_fail_reason_string (ptid
, err
);
1067 warning (_("Cannot attach to lwp %d: %s"), lwpid
, reason
.c_str ());
1075 static void async_file_mark (void);
1077 /* Attach to PID. If PID is the tgid, attach to it and all
1081 linux_process_target::attach (unsigned long pid
)
1083 struct process_info
*proc
;
1084 struct thread_info
*initial_thread
;
1085 ptid_t ptid
= ptid_t (pid
, pid
);
1088 proc
= add_linux_process (pid
, 1);
1090 /* Attach to PID. We will check for other threads
1092 err
= attach_lwp (ptid
);
1095 remove_process (proc
);
1097 std::string reason
= linux_ptrace_attach_fail_reason_string (ptid
, err
);
1098 error ("Cannot attach to process %ld: %s", pid
, reason
.c_str ());
1101 /* Don't ignore the initial SIGSTOP if we just attached to this
1102 process. It will be collected by wait shortly. */
1103 initial_thread
= find_thread_ptid (ptid_t (pid
, pid
));
1104 initial_thread
->last_resume_kind
= resume_stop
;
1106 /* We must attach to every LWP. If /proc is mounted, use that to
1107 find them now. On the one hand, the inferior may be using raw
1108 clone instead of using pthreads. On the other hand, even if it
1109 is using pthreads, GDB may not be connected yet (thread_db needs
1110 to do symbol lookups, through qSymbol). Also, thread_db walks
1111 structures in the inferior's address space to find the list of
1112 threads/LWPs, and those structures may well be corrupted. Note
1113 that once thread_db is loaded, we'll still use it to list threads
1114 and associate pthread info with each LWP. */
1115 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1117 /* GDB will shortly read the xml target description for this
1118 process, to figure out the process' architecture. But the target
1119 description is only filled in when the first process/thread in
1120 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1121 that now, otherwise, if GDB is fast enough, it could read the
1122 target description _before_ that initial stop. */
1125 struct lwp_info
*lwp
;
1127 ptid_t pid_ptid
= ptid_t (pid
);
1129 lwpid
= wait_for_event_filtered (pid_ptid
, pid_ptid
, &wstat
, __WALL
);
1130 gdb_assert (lwpid
> 0);
1132 lwp
= find_lwp_pid (ptid_t (lwpid
));
1134 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1136 lwp
->status_pending_p
= 1;
1137 lwp
->status_pending
= wstat
;
1140 initial_thread
->last_resume_kind
= resume_continue
;
1144 gdb_assert (proc
->tdesc
!= NULL
);
1151 last_thread_of_process_p (int pid
)
1153 bool seen_one
= false;
1155 thread_info
*thread
= find_thread (pid
, [&] (thread_info
*thr_arg
)
1159 /* This is the first thread of this process we see. */
1165 /* This is the second thread of this process we see. */
1170 return thread
== NULL
;
1176 linux_kill_one_lwp (struct lwp_info
*lwp
)
1178 struct thread_info
*thr
= get_lwp_thread (lwp
);
1179 int pid
= lwpid_of (thr
);
1181 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1182 there is no signal context, and ptrace(PTRACE_KILL) (or
1183 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1184 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1185 alternative is to kill with SIGKILL. We only need one SIGKILL
1186 per process, not one for each thread. But since we still support
1187 support debugging programs using raw clone without CLONE_THREAD,
1188 we send one for each thread. For years, we used PTRACE_KILL
1189 only, so we're being a bit paranoid about some old kernels where
1190 PTRACE_KILL might work better (dubious if there are any such, but
1191 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1192 second, and so we're fine everywhere. */
1195 kill_lwp (pid
, SIGKILL
);
1198 int save_errno
= errno
;
1200 threads_debug_printf ("kill_lwp (SIGKILL) %s, 0, 0 (%s)",
1201 target_pid_to_str (ptid_of (thr
)).c_str (),
1202 save_errno
? safe_strerror (save_errno
) : "OK");
1206 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1209 int save_errno
= errno
;
1211 threads_debug_printf ("PTRACE_KILL %s, 0, 0 (%s)",
1212 target_pid_to_str (ptid_of (thr
)).c_str (),
1213 save_errno
? safe_strerror (save_errno
) : "OK");
1217 /* Kill LWP and wait for it to die. */
1220 kill_wait_lwp (struct lwp_info
*lwp
)
1222 struct thread_info
*thr
= get_lwp_thread (lwp
);
1223 int pid
= ptid_of (thr
).pid ();
1224 int lwpid
= ptid_of (thr
).lwp ();
1228 threads_debug_printf ("killing lwp %d, for pid: %d", lwpid
, pid
);
1232 linux_kill_one_lwp (lwp
);
1234 /* Make sure it died. Notes:
1236 - The loop is most likely unnecessary.
1238 - We don't use wait_for_event as that could delete lwps
1239 while we're iterating over them. We're not interested in
1240 any pending status at this point, only in making sure all
1241 wait status on the kernel side are collected until the
1244 - We don't use __WALL here as the __WALL emulation relies on
1245 SIGCHLD, and killing a stopped process doesn't generate
1246 one, nor an exit status.
1248 res
= my_waitpid (lwpid
, &wstat
, 0);
1249 if (res
== -1 && errno
== ECHILD
)
1250 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1251 } while (res
> 0 && WIFSTOPPED (wstat
));
1253 /* Even if it was stopped, the child may have already disappeared.
1254 E.g., if it was killed by SIGKILL. */
1255 if (res
< 0 && errno
!= ECHILD
)
1256 perror_with_name ("kill_wait_lwp");
1259 /* Callback for `for_each_thread'. Kills an lwp of a given process,
1260 except the leader. */
1263 kill_one_lwp_callback (thread_info
*thread
, int pid
)
1265 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1267 /* We avoid killing the first thread here, because of a Linux kernel (at
1268 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1269 the children get a chance to be reaped, it will remain a zombie
1272 if (lwpid_of (thread
) == pid
)
1274 threads_debug_printf ("is last of process %s",
1275 target_pid_to_str (thread
->id
).c_str ());
1279 kill_wait_lwp (lwp
);
1283 linux_process_target::kill (process_info
*process
)
1285 int pid
= process
->pid
;
1287 /* If we're killing a running inferior, make sure it is stopped
1288 first, as PTRACE_KILL will not work otherwise. */
1289 stop_all_lwps (0, NULL
);
1291 for_each_thread (pid
, [&] (thread_info
*thread
)
1293 kill_one_lwp_callback (thread
, pid
);
1296 /* See the comment in linux_kill_one_lwp. We did not kill the first
1297 thread in the list, so do so now. */
1298 lwp_info
*lwp
= find_lwp_pid (ptid_t (pid
));
1301 threads_debug_printf ("cannot find lwp for pid: %d", pid
);
1303 kill_wait_lwp (lwp
);
1307 /* Since we presently can only stop all lwps of all processes, we
1308 need to unstop lwps of other processes. */
1309 unstop_all_lwps (0, NULL
);
1313 /* Get pending signal of THREAD, for detaching purposes. This is the
1314 signal the thread last stopped for, which we need to deliver to the
1315 thread when detaching, otherwise, it'd be suppressed/lost. */
1318 get_detach_signal (struct thread_info
*thread
)
1320 client_state
&cs
= get_client_state ();
1321 enum gdb_signal signo
= GDB_SIGNAL_0
;
1323 struct lwp_info
*lp
= get_thread_lwp (thread
);
1325 if (lp
->status_pending_p
)
1326 status
= lp
->status_pending
;
1329 /* If the thread had been suspended by gdbserver, and it stopped
1330 cleanly, then it'll have stopped with SIGSTOP. But we don't
1331 want to deliver that SIGSTOP. */
1332 if (thread
->last_status
.kind () != TARGET_WAITKIND_STOPPED
1333 || thread
->last_status
.sig () == GDB_SIGNAL_0
)
1336 /* Otherwise, we may need to deliver the signal we
1338 status
= lp
->last_status
;
1341 if (!WIFSTOPPED (status
))
1343 threads_debug_printf ("lwp %s hasn't stopped: no pending signal",
1344 target_pid_to_str (ptid_of (thread
)).c_str ());
1348 /* Extended wait statuses aren't real SIGTRAPs. */
1349 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1351 threads_debug_printf ("lwp %s had stopped with extended "
1352 "status: no pending signal",
1353 target_pid_to_str (ptid_of (thread
)).c_str ());
1357 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1359 if (cs
.program_signals_p
&& !cs
.program_signals
[signo
])
1361 threads_debug_printf ("lwp %s had signal %s, but it is in nopass state",
1362 target_pid_to_str (ptid_of (thread
)).c_str (),
1363 gdb_signal_to_string (signo
));
1366 else if (!cs
.program_signals_p
1367 /* If we have no way to know which signals GDB does not
1368 want to have passed to the program, assume
1369 SIGTRAP/SIGINT, which is GDB's default. */
1370 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1372 threads_debug_printf ("lwp %s had signal %s, "
1373 "but we don't know if we should pass it. "
1375 target_pid_to_str (ptid_of (thread
)).c_str (),
1376 gdb_signal_to_string (signo
));
1381 threads_debug_printf ("lwp %s has pending signal %s: delivering it",
1382 target_pid_to_str (ptid_of (thread
)).c_str (),
1383 gdb_signal_to_string (signo
));
1385 return WSTOPSIG (status
);
1390 linux_process_target::detach_one_lwp (lwp_info
*lwp
)
1392 struct thread_info
*thread
= get_lwp_thread (lwp
);
1396 /* If there is a pending SIGSTOP, get rid of it. */
1397 if (lwp
->stop_expected
)
1399 threads_debug_printf ("Sending SIGCONT to %s",
1400 target_pid_to_str (ptid_of (thread
)).c_str ());
1402 kill_lwp (lwpid_of (thread
), SIGCONT
);
1403 lwp
->stop_expected
= 0;
1406 /* Pass on any pending signal for this thread. */
1407 sig
= get_detach_signal (thread
);
1409 /* Preparing to resume may try to write registers, and fail if the
1410 lwp is zombie. If that happens, ignore the error. We'll handle
1411 it below, when detach fails with ESRCH. */
1414 /* Flush any pending changes to the process's registers. */
1415 regcache_invalidate_thread (thread
);
1417 /* Finally, let it resume. */
1418 low_prepare_to_resume (lwp
);
1420 catch (const gdb_exception_error
&ex
)
1422 if (!check_ptrace_stopped_lwp_gone (lwp
))
1426 lwpid
= lwpid_of (thread
);
1427 if (ptrace (PTRACE_DETACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0,
1428 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1430 int save_errno
= errno
;
1432 /* We know the thread exists, so ESRCH must mean the lwp is
1433 zombie. This can happen if one of the already-detached
1434 threads exits the whole thread group. In that case we're
1435 still attached, and must reap the lwp. */
1436 if (save_errno
== ESRCH
)
1440 ret
= my_waitpid (lwpid
, &status
, __WALL
);
1443 warning (_("Couldn't reap LWP %d while detaching: %s"),
1444 lwpid
, safe_strerror (errno
));
1446 else if (!WIFEXITED (status
) && !WIFSIGNALED (status
))
1448 warning (_("Reaping LWP %d while detaching "
1449 "returned unexpected status 0x%x"),
1455 error (_("Can't detach %s: %s"),
1456 target_pid_to_str (ptid_of (thread
)).c_str (),
1457 safe_strerror (save_errno
));
1461 threads_debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)",
1462 target_pid_to_str (ptid_of (thread
)).c_str (),
1469 linux_process_target::detach (process_info
*process
)
1471 struct lwp_info
*main_lwp
;
1473 /* As there's a step over already in progress, let it finish first,
1474 otherwise nesting a stabilize_threads operation on top gets real
1476 complete_ongoing_step_over ();
1478 /* Stop all threads before detaching. First, ptrace requires that
1479 the thread is stopped to successfully detach. Second, thread_db
1480 may need to uninstall thread event breakpoints from memory, which
1481 only works with a stopped process anyway. */
1482 stop_all_lwps (0, NULL
);
1484 #ifdef USE_THREAD_DB
1485 thread_db_detach (process
);
1488 /* Stabilize threads (move out of jump pads). */
1489 target_stabilize_threads ();
1491 /* Detach from the clone lwps first. If the thread group exits just
1492 while we're detaching, we must reap the clone lwps before we're
1493 able to reap the leader. */
1494 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1496 /* We don't actually detach from the thread group leader just yet.
1497 If the thread group exits, we must reap the zombie clone lwps
1498 before we're able to reap the leader. */
1499 if (thread
->id
.pid () == thread
->id
.lwp ())
1502 lwp_info
*lwp
= get_thread_lwp (thread
);
1503 detach_one_lwp (lwp
);
1506 main_lwp
= find_lwp_pid (ptid_t (process
->pid
));
1507 detach_one_lwp (main_lwp
);
1511 /* Since we presently can only stop all lwps of all processes, we
1512 need to unstop lwps of other processes. */
1513 unstop_all_lwps (0, NULL
);
1517 /* Remove all LWPs that belong to process PROC from the lwp list. */
1520 linux_process_target::mourn (process_info
*process
)
1522 struct process_info_private
*priv
;
1524 #ifdef USE_THREAD_DB
1525 thread_db_mourn (process
);
1528 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1530 delete_lwp (get_thread_lwp (thread
));
1533 /* Freeing all private data. */
1534 priv
= process
->priv
;
1535 low_delete_process (priv
->arch_private
);
1537 process
->priv
= NULL
;
1539 remove_process (process
);
1543 linux_process_target::join (int pid
)
1548 ret
= my_waitpid (pid
, &status
, 0);
1549 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1551 } while (ret
!= -1 || errno
!= ECHILD
);
1554 /* Return true if the given thread is still alive. */
1557 linux_process_target::thread_alive (ptid_t ptid
)
1559 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1561 /* We assume we always know if a thread exits. If a whole process
1562 exited but we still haven't been able to report it to GDB, we'll
1563 hold on to the last lwp of the dead process. */
1565 return !lwp_is_marked_dead (lwp
);
1571 linux_process_target::thread_still_has_status_pending (thread_info
*thread
)
1573 struct lwp_info
*lp
= get_thread_lwp (thread
);
1575 if (!lp
->status_pending_p
)
1578 if (thread
->last_resume_kind
!= resume_stop
1579 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1580 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1585 gdb_assert (lp
->last_status
!= 0);
1589 scoped_restore_current_thread restore_thread
;
1590 switch_to_thread (thread
);
1592 if (pc
!= lp
->stop_pc
)
1594 threads_debug_printf ("PC of %ld changed",
1599 #if !USE_SIGTRAP_SIGINFO
1600 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1601 && !low_breakpoint_at (pc
))
1603 threads_debug_printf ("previous SW breakpoint of %ld gone",
1607 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1608 && !hardware_breakpoint_inserted_here (pc
))
1610 threads_debug_printf ("previous HW breakpoint of %ld gone",
1618 threads_debug_printf ("discarding pending breakpoint status");
1619 lp
->status_pending_p
= 0;
1627 /* Returns true if LWP is resumed from the client's perspective. */
1630 lwp_resumed (struct lwp_info
*lwp
)
1632 struct thread_info
*thread
= get_lwp_thread (lwp
);
1634 if (thread
->last_resume_kind
!= resume_stop
)
1637 /* Did gdb send us a `vCont;t', but we haven't reported the
1638 corresponding stop to gdb yet? If so, the thread is still
1639 resumed/running from gdb's perspective. */
1640 if (thread
->last_resume_kind
== resume_stop
1641 && thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
)
1648 linux_process_target::status_pending_p_callback (thread_info
*thread
,
1651 struct lwp_info
*lp
= get_thread_lwp (thread
);
1653 /* Check if we're only interested in events from a specific process
1654 or a specific LWP. */
1655 if (!thread
->id
.matches (ptid
))
1658 if (!lwp_resumed (lp
))
1661 if (lp
->status_pending_p
1662 && !thread_still_has_status_pending (thread
))
1664 resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1668 return lp
->status_pending_p
;
1672 find_lwp_pid (ptid_t ptid
)
1674 thread_info
*thread
= find_thread ([&] (thread_info
*thr_arg
)
1676 int lwp
= ptid
.lwp () != 0 ? ptid
.lwp () : ptid
.pid ();
1677 return thr_arg
->id
.lwp () == lwp
;
1683 return get_thread_lwp (thread
);
1686 /* Return the number of known LWPs in the tgid given by PID. */
1693 for_each_thread (pid
, [&] (thread_info
*thread
)
1701 /* See nat/linux-nat.h. */
1704 iterate_over_lwps (ptid_t filter
,
1705 gdb::function_view
<iterate_over_lwps_ftype
> callback
)
1707 thread_info
*thread
= find_thread (filter
, [&] (thread_info
*thr_arg
)
1709 lwp_info
*lwp
= get_thread_lwp (thr_arg
);
1711 return callback (lwp
);
1717 return get_thread_lwp (thread
);
1721 linux_process_target::check_zombie_leaders ()
1723 for_each_process ([this] (process_info
*proc
) {
1724 pid_t leader_pid
= pid_of (proc
);
1725 struct lwp_info
*leader_lp
;
1727 leader_lp
= find_lwp_pid (ptid_t (leader_pid
));
1729 threads_debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1730 "num_lwps=%d, zombie=%d",
1731 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1732 linux_proc_pid_is_zombie (leader_pid
));
1734 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1735 /* Check if there are other threads in the group, as we may
1736 have raced with the inferior simply exiting. */
1737 && !last_thread_of_process_p (leader_pid
)
1738 && linux_proc_pid_is_zombie (leader_pid
))
1740 /* A leader zombie can mean one of two things:
1742 - It exited, and there's an exit status pending
1743 available, or only the leader exited (not the whole
1744 program). In the latter case, we can't waitpid the
1745 leader's exit status until all other threads are gone.
1747 - There are 3 or more threads in the group, and a thread
1748 other than the leader exec'd. On an exec, the Linux
1749 kernel destroys all other threads (except the execing
1750 one) in the thread group, and resets the execing thread's
1751 tid to the tgid. No exit notification is sent for the
1752 execing thread -- from the ptracer's perspective, it
1753 appears as though the execing thread just vanishes.
1754 Until we reap all other threads except the leader and the
1755 execing thread, the leader will be zombie, and the
1756 execing thread will be in `D (disc sleep)'. As soon as
1757 all other threads are reaped, the execing thread changes
1758 it's tid to the tgid, and the previous (zombie) leader
1759 vanishes, giving place to the "new" leader. We could try
1760 distinguishing the exit and exec cases, by waiting once
1761 more, and seeing if something comes out, but it doesn't
1762 sound useful. The previous leader _does_ go away, and
1763 we'll re-add the new one once we see the exec event
1764 (which is just the same as what would happen if the
1765 previous leader did exit voluntarily before some other
1768 threads_debug_printf ("Thread group leader %d zombie "
1769 "(it exited, or another thread execd).",
1772 delete_lwp (leader_lp
);
1777 /* Callback for `find_thread'. Returns the first LWP that is not
1781 not_stopped_callback (thread_info
*thread
, ptid_t filter
)
1783 if (!thread
->id
.matches (filter
))
1786 lwp_info
*lwp
= get_thread_lwp (thread
);
1788 return !lwp
->stopped
;
1791 /* Increment LWP's suspend count. */
1794 lwp_suspended_inc (struct lwp_info
*lwp
)
1798 if (lwp
->suspended
> 4)
1799 threads_debug_printf
1800 ("LWP %ld has a suspiciously high suspend count, suspended=%d",
1801 lwpid_of (get_lwp_thread (lwp
)), lwp
->suspended
);
1804 /* Decrement LWP's suspend count. */
1807 lwp_suspended_decr (struct lwp_info
*lwp
)
1811 if (lwp
->suspended
< 0)
1813 struct thread_info
*thread
= get_lwp_thread (lwp
);
1815 internal_error (__FILE__
, __LINE__
,
1816 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1821 /* This function should only be called if the LWP got a SIGTRAP.
1823 Handle any tracepoint steps or hits. Return true if a tracepoint
1824 event was handled, 0 otherwise. */
1827 handle_tracepoints (struct lwp_info
*lwp
)
1829 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1830 int tpoint_related_event
= 0;
1832 gdb_assert (lwp
->suspended
== 0);
1834 /* If this tracepoint hit causes a tracing stop, we'll immediately
1835 uninsert tracepoints. To do this, we temporarily pause all
1836 threads, unpatch away, and then unpause threads. We need to make
1837 sure the unpausing doesn't resume LWP too. */
1838 lwp_suspended_inc (lwp
);
1840 /* And we need to be sure that any all-threads-stopping doesn't try
1841 to move threads out of the jump pads, as it could deadlock the
1842 inferior (LWP could be in the jump pad, maybe even holding the
1845 /* Do any necessary step collect actions. */
1846 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1848 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1850 /* See if we just hit a tracepoint and do its main collect
1852 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1854 lwp_suspended_decr (lwp
);
1856 gdb_assert (lwp
->suspended
== 0);
1857 gdb_assert (!stabilizing_threads
1858 || (lwp
->collecting_fast_tracepoint
1859 != fast_tpoint_collect_result::not_collecting
));
1861 if (tpoint_related_event
)
1863 threads_debug_printf ("got a tracepoint event");
1870 fast_tpoint_collect_result
1871 linux_process_target::linux_fast_tracepoint_collecting
1872 (lwp_info
*lwp
, fast_tpoint_collect_status
*status
)
1874 CORE_ADDR thread_area
;
1875 struct thread_info
*thread
= get_lwp_thread (lwp
);
1877 /* Get the thread area address. This is used to recognize which
1878 thread is which when tracing with the in-process agent library.
1879 We don't read anything from the address, and treat it as opaque;
1880 it's the address itself that we assume is unique per-thread. */
1881 if (low_get_thread_area (lwpid_of (thread
), &thread_area
) == -1)
1882 return fast_tpoint_collect_result::not_collecting
;
1884 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1888 linux_process_target::low_get_thread_area (int lwpid
, CORE_ADDR
*addrp
)
1894 linux_process_target::maybe_move_out_of_jump_pad (lwp_info
*lwp
, int *wstat
)
1896 scoped_restore_current_thread restore_thread
;
1897 switch_to_thread (get_lwp_thread (lwp
));
1900 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1901 && supports_fast_tracepoints ()
1902 && agent_loaded_p ())
1904 struct fast_tpoint_collect_status status
;
1906 threads_debug_printf
1907 ("Checking whether LWP %ld needs to move out of the jump pad.",
1908 lwpid_of (current_thread
));
1910 fast_tpoint_collect_result r
1911 = linux_fast_tracepoint_collecting (lwp
, &status
);
1914 || (WSTOPSIG (*wstat
) != SIGILL
1915 && WSTOPSIG (*wstat
) != SIGFPE
1916 && WSTOPSIG (*wstat
) != SIGSEGV
1917 && WSTOPSIG (*wstat
) != SIGBUS
))
1919 lwp
->collecting_fast_tracepoint
= r
;
1921 if (r
!= fast_tpoint_collect_result::not_collecting
)
1923 if (r
== fast_tpoint_collect_result::before_insn
1924 && lwp
->exit_jump_pad_bkpt
== NULL
)
1926 /* Haven't executed the original instruction yet.
1927 Set breakpoint there, and wait till it's hit,
1928 then single-step until exiting the jump pad. */
1929 lwp
->exit_jump_pad_bkpt
1930 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1933 threads_debug_printf
1934 ("Checking whether LWP %ld needs to move out of the jump pad..."
1935 " it does", lwpid_of (current_thread
));
1942 /* If we get a synchronous signal while collecting, *and*
1943 while executing the (relocated) original instruction,
1944 reset the PC to point at the tpoint address, before
1945 reporting to GDB. Otherwise, it's an IPA lib bug: just
1946 report the signal to GDB, and pray for the best. */
1948 lwp
->collecting_fast_tracepoint
1949 = fast_tpoint_collect_result::not_collecting
;
1951 if (r
!= fast_tpoint_collect_result::not_collecting
1952 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1953 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1956 struct regcache
*regcache
;
1958 /* The si_addr on a few signals references the address
1959 of the faulting instruction. Adjust that as
1961 if ((WSTOPSIG (*wstat
) == SIGILL
1962 || WSTOPSIG (*wstat
) == SIGFPE
1963 || WSTOPSIG (*wstat
) == SIGBUS
1964 || WSTOPSIG (*wstat
) == SIGSEGV
)
1965 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
1966 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
1967 /* Final check just to make sure we don't clobber
1968 the siginfo of non-kernel-sent signals. */
1969 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1971 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1972 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
1973 (PTRACE_TYPE_ARG3
) 0, &info
);
1976 regcache
= get_thread_regcache (current_thread
, 1);
1977 low_set_pc (regcache
, status
.tpoint_addr
);
1978 lwp
->stop_pc
= status
.tpoint_addr
;
1980 /* Cancel any fast tracepoint lock this thread was
1982 force_unlock_trace_buffer ();
1985 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1987 threads_debug_printf
1988 ("Cancelling fast exit-jump-pad: removing bkpt."
1989 "stopping all threads momentarily.");
1991 stop_all_lwps (1, lwp
);
1993 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1994 lwp
->exit_jump_pad_bkpt
= NULL
;
1996 unstop_all_lwps (1, lwp
);
1998 gdb_assert (lwp
->suspended
>= 0);
2003 threads_debug_printf
2004 ("Checking whether LWP %ld needs to move out of the jump pad... no",
2005 lwpid_of (current_thread
));
2010 /* Enqueue one signal in the "signals to report later when out of the
2014 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2016 struct thread_info
*thread
= get_lwp_thread (lwp
);
2018 threads_debug_printf ("Deferring signal %d for LWP %ld.",
2019 WSTOPSIG (*wstat
), lwpid_of (thread
));
2023 for (const auto &sig
: lwp
->pending_signals_to_report
)
2024 threads_debug_printf (" Already queued %d", sig
.signal
);
2026 threads_debug_printf (" (no more currently queued signals)");
2029 /* Don't enqueue non-RT signals if they are already in the deferred
2030 queue. (SIGSTOP being the easiest signal to see ending up here
2032 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2034 for (const auto &sig
: lwp
->pending_signals_to_report
)
2036 if (sig
.signal
== WSTOPSIG (*wstat
))
2038 threads_debug_printf
2039 ("Not requeuing already queued non-RT signal %d for LWP %ld",
2040 sig
.signal
, lwpid_of (thread
));
2046 lwp
->pending_signals_to_report
.emplace_back (WSTOPSIG (*wstat
));
2048 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2049 &lwp
->pending_signals_to_report
.back ().info
);
2052 /* Dequeue one signal from the "signals to report later when out of
2053 the jump pad" list. */
2056 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2058 struct thread_info
*thread
= get_lwp_thread (lwp
);
2060 if (!lwp
->pending_signals_to_report
.empty ())
2062 const pending_signal
&p_sig
= lwp
->pending_signals_to_report
.front ();
2064 *wstat
= W_STOPCODE (p_sig
.signal
);
2065 if (p_sig
.info
.si_signo
!= 0)
2066 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2069 lwp
->pending_signals_to_report
.pop_front ();
2071 threads_debug_printf ("Reporting deferred signal %d for LWP %ld.",
2072 WSTOPSIG (*wstat
), lwpid_of (thread
));
2076 for (const auto &sig
: lwp
->pending_signals_to_report
)
2077 threads_debug_printf (" Still queued %d", sig
.signal
);
2079 threads_debug_printf (" (no more queued signals)");
2089 linux_process_target::check_stopped_by_watchpoint (lwp_info
*child
)
2091 scoped_restore_current_thread restore_thread
;
2092 switch_to_thread (get_lwp_thread (child
));
2094 if (low_stopped_by_watchpoint ())
2096 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2097 child
->stopped_data_address
= low_stopped_data_address ();
2100 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2104 linux_process_target::low_stopped_by_watchpoint ()
2110 linux_process_target::low_stopped_data_address ()
2115 /* Return the ptrace options that we want to try to enable. */
2118 linux_low_ptrace_options (int attached
)
2120 client_state
&cs
= get_client_state ();
2124 options
|= PTRACE_O_EXITKILL
;
2126 if (cs
.report_fork_events
)
2127 options
|= PTRACE_O_TRACEFORK
;
2129 if (cs
.report_vfork_events
)
2130 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2132 if (cs
.report_exec_events
)
2133 options
|= PTRACE_O_TRACEEXEC
;
2135 options
|= PTRACE_O_TRACESYSGOOD
;
2141 linux_process_target::filter_event (int lwpid
, int wstat
)
2143 client_state
&cs
= get_client_state ();
2144 struct lwp_info
*child
;
2145 struct thread_info
*thread
;
2146 int have_stop_pc
= 0;
2148 child
= find_lwp_pid (ptid_t (lwpid
));
2150 /* Check for stop events reported by a process we didn't already
2151 know about - anything not already in our LWP list.
2153 If we're expecting to receive stopped processes after
2154 fork, vfork, and clone events, then we'll just add the
2155 new one to our list and go back to waiting for the event
2156 to be reported - the stopped process might be returned
2157 from waitpid before or after the event is.
2159 But note the case of a non-leader thread exec'ing after the
2160 leader having exited, and gone from our lists (because
2161 check_zombie_leaders deleted it). The non-leader thread
2162 changes its tid to the tgid. */
2164 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2165 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2169 /* A multi-thread exec after we had seen the leader exiting. */
2170 threads_debug_printf ("Re-adding thread group leader LWP %d after exec.",
2173 child_ptid
= ptid_t (lwpid
, lwpid
);
2174 child
= add_lwp (child_ptid
);
2176 switch_to_thread (child
->thread
);
2179 /* If we didn't find a process, one of two things presumably happened:
2180 - A process we started and then detached from has exited. Ignore it.
2181 - A process we are controlling has forked and the new child's stop
2182 was reported to us by the kernel. Save its PID. */
2183 if (child
== NULL
&& WIFSTOPPED (wstat
))
2185 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2188 else if (child
== NULL
)
2191 thread
= get_lwp_thread (child
);
2195 child
->last_status
= wstat
;
2197 /* Check if the thread has exited. */
2198 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2200 threads_debug_printf ("%d exited", lwpid
);
2202 if (finish_step_over (child
))
2204 /* Unsuspend all other LWPs, and set them back running again. */
2205 unsuspend_all_lwps (child
);
2208 /* If there is at least one more LWP, then the exit signal was
2209 not the end of the debugged application and should be
2210 ignored, unless GDB wants to hear about thread exits. */
2211 if (cs
.report_thread_events
2212 || last_thread_of_process_p (pid_of (thread
)))
2214 /* Since events are serialized to GDB core, and we can't
2215 report this one right now. Leave the status pending for
2216 the next time we're able to report it. */
2217 mark_lwp_dead (child
, wstat
);
2227 gdb_assert (WIFSTOPPED (wstat
));
2229 if (WIFSTOPPED (wstat
))
2231 struct process_info
*proc
;
2233 /* Architecture-specific setup after inferior is running. */
2234 proc
= find_process_pid (pid_of (thread
));
2235 if (proc
->tdesc
== NULL
)
2239 /* This needs to happen after we have attached to the
2240 inferior and it is stopped for the first time, but
2241 before we access any inferior registers. */
2242 arch_setup_thread (thread
);
2246 /* The process is started, but GDBserver will do
2247 architecture-specific setup after the program stops at
2248 the first instruction. */
2249 child
->status_pending_p
= 1;
2250 child
->status_pending
= wstat
;
2256 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2258 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2259 int options
= linux_low_ptrace_options (proc
->attached
);
2261 linux_enable_event_reporting (lwpid
, options
);
2262 child
->must_set_ptrace_flags
= 0;
2265 /* Always update syscall_state, even if it will be filtered later. */
2266 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2268 child
->syscall_state
2269 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2270 ? TARGET_WAITKIND_SYSCALL_RETURN
2271 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2275 /* Almost all other ptrace-stops are known to be outside of system
2276 calls, with further exceptions in handle_extended_wait. */
2277 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2280 /* Be careful to not overwrite stop_pc until save_stop_reason is
2282 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2283 && linux_is_extended_waitstatus (wstat
))
2285 child
->stop_pc
= get_pc (child
);
2286 if (handle_extended_wait (&child
, wstat
))
2288 /* The event has been handled, so just return without
2294 if (linux_wstatus_maybe_breakpoint (wstat
))
2296 if (save_stop_reason (child
))
2301 child
->stop_pc
= get_pc (child
);
2303 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2304 && child
->stop_expected
)
2306 threads_debug_printf ("Expected stop.");
2308 child
->stop_expected
= 0;
2310 if (thread
->last_resume_kind
== resume_stop
)
2312 /* We want to report the stop to the core. Treat the
2313 SIGSTOP as a normal event. */
2314 threads_debug_printf ("resume_stop SIGSTOP caught for %s.",
2315 target_pid_to_str (ptid_of (thread
)).c_str ());
2317 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2319 /* Stopping threads. We don't want this SIGSTOP to end up
2321 threads_debug_printf ("SIGSTOP caught for %s while stopping threads.",
2322 target_pid_to_str (ptid_of (thread
)).c_str ());
2327 /* This is a delayed SIGSTOP. Filter out the event. */
2328 threads_debug_printf ("%s %s, 0, 0 (discard delayed SIGSTOP)",
2329 child
->stepping
? "step" : "continue",
2330 target_pid_to_str (ptid_of (thread
)).c_str ());
2332 resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2337 child
->status_pending_p
= 1;
2338 child
->status_pending
= wstat
;
2343 linux_process_target::maybe_hw_step (thread_info
*thread
)
2345 if (supports_hardware_single_step ())
2349 /* GDBserver must insert single-step breakpoint for software
2351 gdb_assert (has_single_step_breakpoints (thread
));
2357 linux_process_target::resume_stopped_resumed_lwps (thread_info
*thread
)
2359 struct lwp_info
*lp
= get_thread_lwp (thread
);
2363 && !lp
->status_pending_p
2364 && thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
)
2368 if (thread
->last_resume_kind
== resume_step
)
2369 step
= maybe_hw_step (thread
);
2371 threads_debug_printf ("resuming stopped-resumed LWP %s at %s: step=%d",
2372 target_pid_to_str (ptid_of (thread
)).c_str (),
2373 paddress (lp
->stop_pc
), step
);
2375 resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2380 linux_process_target::wait_for_event_filtered (ptid_t wait_ptid
,
2382 int *wstatp
, int options
)
2384 struct thread_info
*event_thread
;
2385 struct lwp_info
*event_child
, *requested_child
;
2386 sigset_t block_mask
, prev_mask
;
2389 /* N.B. event_thread points to the thread_info struct that contains
2390 event_child. Keep them in sync. */
2391 event_thread
= NULL
;
2393 requested_child
= NULL
;
2395 /* Check for a lwp with a pending status. */
2397 if (filter_ptid
== minus_one_ptid
|| filter_ptid
.is_pid ())
2399 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2401 return status_pending_p_callback (thread
, filter_ptid
);
2404 if (event_thread
!= NULL
)
2406 event_child
= get_thread_lwp (event_thread
);
2407 threads_debug_printf ("Got a pending child %ld", lwpid_of (event_thread
));
2410 else if (filter_ptid
!= null_ptid
)
2412 requested_child
= find_lwp_pid (filter_ptid
);
2414 if (stopping_threads
== NOT_STOPPING_THREADS
2415 && requested_child
->status_pending_p
2416 && (requested_child
->collecting_fast_tracepoint
2417 != fast_tpoint_collect_result::not_collecting
))
2419 enqueue_one_deferred_signal (requested_child
,
2420 &requested_child
->status_pending
);
2421 requested_child
->status_pending_p
= 0;
2422 requested_child
->status_pending
= 0;
2423 resume_one_lwp (requested_child
, 0, 0, NULL
);
2426 if (requested_child
->suspended
2427 && requested_child
->status_pending_p
)
2429 internal_error (__FILE__
, __LINE__
,
2430 "requesting an event out of a"
2431 " suspended child?");
2434 if (requested_child
->status_pending_p
)
2436 event_child
= requested_child
;
2437 event_thread
= get_lwp_thread (event_child
);
2441 if (event_child
!= NULL
)
2443 threads_debug_printf ("Got an event from pending child %ld (%04x)",
2444 lwpid_of (event_thread
),
2445 event_child
->status_pending
);
2447 *wstatp
= event_child
->status_pending
;
2448 event_child
->status_pending_p
= 0;
2449 event_child
->status_pending
= 0;
2450 switch_to_thread (event_thread
);
2451 return lwpid_of (event_thread
);
2454 /* But if we don't find a pending event, we'll have to wait.
2456 We only enter this loop if no process has a pending wait status.
2457 Thus any action taken in response to a wait status inside this
2458 loop is responding as soon as we detect the status, not after any
2461 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2462 all signals while here. */
2463 sigfillset (&block_mask
);
2464 gdb_sigmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2466 /* Always pull all events out of the kernel. We'll randomly select
2467 an event LWP out of all that have events, to prevent
2469 while (event_child
== NULL
)
2473 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2476 - If the thread group leader exits while other threads in the
2477 thread group still exist, waitpid(TGID, ...) hangs. That
2478 waitpid won't return an exit status until the other threads
2479 in the group are reaped.
2481 - When a non-leader thread execs, that thread just vanishes
2482 without reporting an exit (so we'd hang if we waited for it
2483 explicitly in that case). The exec event is reported to
2486 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2488 threads_debug_printf ("waitpid(-1, ...) returned %d, %s",
2489 ret
, errno
? safe_strerror (errno
) : "ERRNO-OK");
2493 threads_debug_printf ("waitpid %ld received %s",
2494 (long) ret
, status_to_str (*wstatp
).c_str ());
2496 /* Filter all events. IOW, leave all events pending. We'll
2497 randomly select an event LWP out of all that have events
2499 filter_event (ret
, *wstatp
);
2500 /* Retry until nothing comes out of waitpid. A single
2501 SIGCHLD can indicate more than one child stopped. */
2505 /* Now that we've pulled all events out of the kernel, resume
2506 LWPs that don't have an interesting event to report. */
2507 if (stopping_threads
== NOT_STOPPING_THREADS
)
2508 for_each_thread ([this] (thread_info
*thread
)
2510 resume_stopped_resumed_lwps (thread
);
2513 /* ... and find an LWP with a status to report to the core, if
2515 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2517 return status_pending_p_callback (thread
, filter_ptid
);
2520 if (event_thread
!= NULL
)
2522 event_child
= get_thread_lwp (event_thread
);
2523 *wstatp
= event_child
->status_pending
;
2524 event_child
->status_pending_p
= 0;
2525 event_child
->status_pending
= 0;
2529 /* Check for zombie thread group leaders. Those can't be reaped
2530 until all other threads in the thread group are. */
2531 check_zombie_leaders ();
2533 auto not_stopped
= [&] (thread_info
*thread
)
2535 return not_stopped_callback (thread
, wait_ptid
);
2538 /* If there are no resumed children left in the set of LWPs we
2539 want to wait for, bail. We can't just block in
2540 waitpid/sigsuspend, because lwps might have been left stopped
2541 in trace-stop state, and we'd be stuck forever waiting for
2542 their status to change (which would only happen if we resumed
2543 them). Even if WNOHANG is set, this return code is preferred
2544 over 0 (below), as it is more detailed. */
2545 if (find_thread (not_stopped
) == NULL
)
2547 threads_debug_printf ("exit (no unwaited-for LWP)");
2549 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2553 /* No interesting event to report to the caller. */
2554 if ((options
& WNOHANG
))
2556 threads_debug_printf ("WNOHANG set, no event found");
2558 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2562 /* Block until we get an event reported with SIGCHLD. */
2563 threads_debug_printf ("sigsuspend'ing");
2565 sigsuspend (&prev_mask
);
2566 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2570 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2572 switch_to_thread (event_thread
);
2574 return lwpid_of (event_thread
);
2578 linux_process_target::wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2580 return wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2583 /* Select one LWP out of those that have events pending. */
2586 select_event_lwp (struct lwp_info
**orig_lp
)
2588 struct thread_info
*event_thread
= NULL
;
2590 /* In all-stop, give preference to the LWP that is being
2591 single-stepped. There will be at most one, and it's the LWP that
2592 the core is most interested in. If we didn't do this, then we'd
2593 have to handle pending step SIGTRAPs somehow in case the core
2594 later continues the previously-stepped thread, otherwise we'd
2595 report the pending SIGTRAP, and the core, not having stepped the
2596 thread, wouldn't understand what the trap was for, and therefore
2597 would report it to the user as a random signal. */
2600 event_thread
= find_thread ([] (thread_info
*thread
)
2602 lwp_info
*lp
= get_thread_lwp (thread
);
2604 return (thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
2605 && thread
->last_resume_kind
== resume_step
2606 && lp
->status_pending_p
);
2609 if (event_thread
!= NULL
)
2610 threads_debug_printf
2611 ("Select single-step %s",
2612 target_pid_to_str (ptid_of (event_thread
)).c_str ());
2614 if (event_thread
== NULL
)
2616 /* No single-stepping LWP. Select one at random, out of those
2617 which have had events. */
2619 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2621 lwp_info
*lp
= get_thread_lwp (thread
);
2623 /* Only resumed LWPs that have an event pending. */
2624 return (thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
2625 && lp
->status_pending_p
);
2629 if (event_thread
!= NULL
)
2631 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2633 /* Switch the event LWP. */
2634 *orig_lp
= event_lp
;
2638 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2642 unsuspend_all_lwps (struct lwp_info
*except
)
2644 for_each_thread ([&] (thread_info
*thread
)
2646 lwp_info
*lwp
= get_thread_lwp (thread
);
2649 lwp_suspended_decr (lwp
);
2653 static bool lwp_running (thread_info
*thread
);
2655 /* Stabilize threads (move out of jump pads).
2657 If a thread is midway collecting a fast tracepoint, we need to
2658 finish the collection and move it out of the jump pad before
2659 reporting the signal.
2661 This avoids recursion while collecting (when a signal arrives
2662 midway, and the signal handler itself collects), which would trash
2663 the trace buffer. In case the user set a breakpoint in a signal
2664 handler, this avoids the backtrace showing the jump pad, etc..
2665 Most importantly, there are certain things we can't do safely if
2666 threads are stopped in a jump pad (or in its callee's). For
2669 - starting a new trace run. A thread still collecting the
2670 previous run, could trash the trace buffer when resumed. The trace
2671 buffer control structures would have been reset but the thread had
2672 no way to tell. The thread could even midway memcpy'ing to the
2673 buffer, which would mean that when resumed, it would clobber the
2674 trace buffer that had been set for a new run.
2676 - we can't rewrite/reuse the jump pads for new tracepoints
2677 safely. Say you do tstart while a thread is stopped midway while
2678 collecting. When the thread is later resumed, it finishes the
2679 collection, and returns to the jump pad, to execute the original
2680 instruction that was under the tracepoint jump at the time the
2681 older run had been started. If the jump pad had been rewritten
2682 since for something else in the new run, the thread would now
2683 execute the wrong / random instructions. */
2686 linux_process_target::stabilize_threads ()
2688 thread_info
*thread_stuck
= find_thread ([this] (thread_info
*thread
)
2690 return stuck_in_jump_pad (thread
);
2693 if (thread_stuck
!= NULL
)
2695 threads_debug_printf ("can't stabilize, LWP %ld is stuck in jump pad",
2696 lwpid_of (thread_stuck
));
2700 scoped_restore_current_thread restore_thread
;
2702 stabilizing_threads
= 1;
2705 for_each_thread ([this] (thread_info
*thread
)
2707 move_out_of_jump_pad (thread
);
2710 /* Loop until all are stopped out of the jump pads. */
2711 while (find_thread (lwp_running
) != NULL
)
2713 struct target_waitstatus ourstatus
;
2714 struct lwp_info
*lwp
;
2717 /* Note that we go through the full wait even loop. While
2718 moving threads out of jump pad, we need to be able to step
2719 over internal breakpoints and such. */
2720 wait_1 (minus_one_ptid
, &ourstatus
, 0);
2722 if (ourstatus
.kind () == TARGET_WAITKIND_STOPPED
)
2724 lwp
= get_thread_lwp (current_thread
);
2727 lwp_suspended_inc (lwp
);
2729 if (ourstatus
.sig () != GDB_SIGNAL_0
2730 || current_thread
->last_resume_kind
== resume_stop
)
2732 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.sig ()));
2733 enqueue_one_deferred_signal (lwp
, &wstat
);
2738 unsuspend_all_lwps (NULL
);
2740 stabilizing_threads
= 0;
2744 thread_stuck
= find_thread ([this] (thread_info
*thread
)
2746 return stuck_in_jump_pad (thread
);
2749 if (thread_stuck
!= NULL
)
2750 threads_debug_printf
2751 ("couldn't stabilize, LWP %ld got stuck in jump pad",
2752 lwpid_of (thread_stuck
));
2756 /* Convenience function that is called when the kernel reports an
2757 event that is not passed out to GDB. */
2760 ignore_event (struct target_waitstatus
*ourstatus
)
2762 /* If we got an event, there may still be others, as a single
2763 SIGCHLD can indicate more than one child stopped. This forces
2764 another target_wait call. */
2767 ourstatus
->set_ignore ();
2772 linux_process_target::filter_exit_event (lwp_info
*event_child
,
2773 target_waitstatus
*ourstatus
)
2775 client_state
&cs
= get_client_state ();
2776 struct thread_info
*thread
= get_lwp_thread (event_child
);
2777 ptid_t ptid
= ptid_of (thread
);
2779 if (!last_thread_of_process_p (pid_of (thread
)))
2781 if (cs
.report_thread_events
)
2782 ourstatus
->set_thread_exited (0);
2784 ourstatus
->set_ignore ();
2786 delete_lwp (event_child
);
2791 /* Returns 1 if GDB is interested in any event_child syscalls. */
2794 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
2796 struct thread_info
*thread
= get_lwp_thread (event_child
);
2797 struct process_info
*proc
= get_thread_process (thread
);
2799 return !proc
->syscalls_to_catch
.empty ();
2803 linux_process_target::gdb_catch_this_syscall (lwp_info
*event_child
)
2806 struct thread_info
*thread
= get_lwp_thread (event_child
);
2807 struct process_info
*proc
= get_thread_process (thread
);
2809 if (proc
->syscalls_to_catch
.empty ())
2812 if (proc
->syscalls_to_catch
[0] == ANY_SYSCALL
)
2815 get_syscall_trapinfo (event_child
, &sysno
);
2817 for (int iter
: proc
->syscalls_to_catch
)
2825 linux_process_target::wait_1 (ptid_t ptid
, target_waitstatus
*ourstatus
,
2826 target_wait_flags target_options
)
2828 THREADS_SCOPED_DEBUG_ENTER_EXIT
;
2830 client_state
&cs
= get_client_state ();
2832 struct lwp_info
*event_child
;
2835 int step_over_finished
;
2836 int bp_explains_trap
;
2837 int maybe_internal_trap
;
2843 threads_debug_printf ("[%s]", target_pid_to_str (ptid
).c_str ());
2845 /* Translate generic target options into linux options. */
2847 if (target_options
& TARGET_WNOHANG
)
2850 bp_explains_trap
= 0;
2853 ourstatus
->set_ignore ();
2855 auto status_pending_p_any
= [&] (thread_info
*thread
)
2857 return status_pending_p_callback (thread
, minus_one_ptid
);
2860 auto not_stopped
= [&] (thread_info
*thread
)
2862 return not_stopped_callback (thread
, minus_one_ptid
);
2865 /* Find a resumed LWP, if any. */
2866 if (find_thread (status_pending_p_any
) != NULL
)
2868 else if (find_thread (not_stopped
) != NULL
)
2873 if (step_over_bkpt
== null_ptid
)
2874 pid
= wait_for_event (ptid
, &w
, options
);
2877 threads_debug_printf ("step_over_bkpt set [%s], doing a blocking wait",
2878 target_pid_to_str (step_over_bkpt
).c_str ());
2879 pid
= wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2882 if (pid
== 0 || (pid
== -1 && !any_resumed
))
2884 gdb_assert (target_options
& TARGET_WNOHANG
);
2886 threads_debug_printf ("ret = null_ptid, TARGET_WAITKIND_IGNORE");
2888 ourstatus
->set_ignore ();
2893 threads_debug_printf ("ret = null_ptid, TARGET_WAITKIND_NO_RESUMED");
2895 ourstatus
->set_no_resumed ();
2899 event_child
= get_thread_lwp (current_thread
);
2901 /* wait_for_event only returns an exit status for the last
2902 child of a process. Report it. */
2903 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2907 ourstatus
->set_exited (WEXITSTATUS (w
));
2909 threads_debug_printf
2910 ("ret = %s, exited with retcode %d",
2911 target_pid_to_str (ptid_of (current_thread
)).c_str (),
2916 ourstatus
->set_signalled (gdb_signal_from_host (WTERMSIG (w
)));
2918 threads_debug_printf
2919 ("ret = %s, terminated with signal %d",
2920 target_pid_to_str (ptid_of (current_thread
)).c_str (),
2924 if (ourstatus
->kind () == TARGET_WAITKIND_EXITED
)
2925 return filter_exit_event (event_child
, ourstatus
);
2927 return ptid_of (current_thread
);
2930 /* If step-over executes a breakpoint instruction, in the case of a
2931 hardware single step it means a gdb/gdbserver breakpoint had been
2932 planted on top of a permanent breakpoint, in the case of a software
2933 single step it may just mean that gdbserver hit the reinsert breakpoint.
2934 The PC has been adjusted by save_stop_reason to point at
2935 the breakpoint address.
2936 So in the case of the hardware single step advance the PC manually
2937 past the breakpoint and in the case of software single step advance only
2938 if it's not the single_step_breakpoint we are hitting.
2939 This avoids that a program would keep trapping a permanent breakpoint
2941 if (step_over_bkpt
!= null_ptid
2942 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
2943 && (event_child
->stepping
2944 || !single_step_breakpoint_inserted_here (event_child
->stop_pc
)))
2946 int increment_pc
= 0;
2947 int breakpoint_kind
= 0;
2948 CORE_ADDR stop_pc
= event_child
->stop_pc
;
2950 breakpoint_kind
= breakpoint_kind_from_current_state (&stop_pc
);
2951 sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
2953 threads_debug_printf
2954 ("step-over for %s executed software breakpoint",
2955 target_pid_to_str (ptid_of (current_thread
)).c_str ());
2957 if (increment_pc
!= 0)
2959 struct regcache
*regcache
2960 = get_thread_regcache (current_thread
, 1);
2962 event_child
->stop_pc
+= increment_pc
;
2963 low_set_pc (regcache
, event_child
->stop_pc
);
2965 if (!low_breakpoint_at (event_child
->stop_pc
))
2966 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2970 /* If this event was not handled before, and is not a SIGTRAP, we
2971 report it. SIGILL and SIGSEGV are also treated as traps in case
2972 a breakpoint is inserted at the current PC. If this target does
2973 not support internal breakpoints at all, we also report the
2974 SIGTRAP without further processing; it's of no concern to us. */
2976 = (low_supports_breakpoints ()
2977 && (WSTOPSIG (w
) == SIGTRAP
2978 || ((WSTOPSIG (w
) == SIGILL
2979 || WSTOPSIG (w
) == SIGSEGV
)
2980 && low_breakpoint_at (event_child
->stop_pc
))));
2982 if (maybe_internal_trap
)
2984 /* Handle anything that requires bookkeeping before deciding to
2985 report the event or continue waiting. */
2987 /* First check if we can explain the SIGTRAP with an internal
2988 breakpoint, or if we should possibly report the event to GDB.
2989 Do this before anything that may remove or insert a
2991 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2993 /* We have a SIGTRAP, possibly a step-over dance has just
2994 finished. If so, tweak the state machine accordingly,
2995 reinsert breakpoints and delete any single-step
2997 step_over_finished
= finish_step_over (event_child
);
2999 /* Now invoke the callbacks of any internal breakpoints there. */
3000 check_breakpoints (event_child
->stop_pc
);
3002 /* Handle tracepoint data collecting. This may overflow the
3003 trace buffer, and cause a tracing stop, removing
3005 trace_event
= handle_tracepoints (event_child
);
3007 if (bp_explains_trap
)
3008 threads_debug_printf ("Hit a gdbserver breakpoint.");
3012 /* We have some other signal, possibly a step-over dance was in
3013 progress, and it should be cancelled too. */
3014 step_over_finished
= finish_step_over (event_child
);
3017 /* We have all the data we need. Either report the event to GDB, or
3018 resume threads and keep waiting for more. */
3020 /* If we're collecting a fast tracepoint, finish the collection and
3021 move out of the jump pad before delivering a signal. See
3022 linux_stabilize_threads. */
3025 && WSTOPSIG (w
) != SIGTRAP
3026 && supports_fast_tracepoints ()
3027 && agent_loaded_p ())
3029 threads_debug_printf ("Got signal %d for LWP %ld. Check if we need "
3030 "to defer or adjust it.",
3031 WSTOPSIG (w
), lwpid_of (current_thread
));
3033 /* Allow debugging the jump pad itself. */
3034 if (current_thread
->last_resume_kind
!= resume_step
3035 && maybe_move_out_of_jump_pad (event_child
, &w
))
3037 enqueue_one_deferred_signal (event_child
, &w
);
3039 threads_debug_printf ("Signal %d for LWP %ld deferred (in jump pad)",
3040 WSTOPSIG (w
), lwpid_of (current_thread
));
3042 resume_one_lwp (event_child
, 0, 0, NULL
);
3044 return ignore_event (ourstatus
);
3048 if (event_child
->collecting_fast_tracepoint
3049 != fast_tpoint_collect_result::not_collecting
)
3051 threads_debug_printf
3052 ("LWP %ld was trying to move out of the jump pad (%d). "
3053 "Check if we're already there.",
3054 lwpid_of (current_thread
),
3055 (int) event_child
->collecting_fast_tracepoint
);
3059 event_child
->collecting_fast_tracepoint
3060 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3062 if (event_child
->collecting_fast_tracepoint
3063 != fast_tpoint_collect_result::before_insn
)
3065 /* No longer need this breakpoint. */
3066 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3068 threads_debug_printf
3069 ("No longer need exit-jump-pad bkpt; removing it."
3070 "stopping all threads momentarily.");
3072 /* Other running threads could hit this breakpoint.
3073 We don't handle moribund locations like GDB does,
3074 instead we always pause all threads when removing
3075 breakpoints, so that any step-over or
3076 decr_pc_after_break adjustment is always taken
3077 care of while the breakpoint is still
3079 stop_all_lwps (1, event_child
);
3081 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3082 event_child
->exit_jump_pad_bkpt
= NULL
;
3084 unstop_all_lwps (1, event_child
);
3086 gdb_assert (event_child
->suspended
>= 0);
3090 if (event_child
->collecting_fast_tracepoint
3091 == fast_tpoint_collect_result::not_collecting
)
3093 threads_debug_printf
3094 ("fast tracepoint finished collecting successfully.");
3096 /* We may have a deferred signal to report. */
3097 if (dequeue_one_deferred_signal (event_child
, &w
))
3098 threads_debug_printf ("dequeued one signal.");
3101 threads_debug_printf ("no deferred signals.");
3103 if (stabilizing_threads
)
3105 ourstatus
->set_stopped (GDB_SIGNAL_0
);
3107 threads_debug_printf
3108 ("ret = %s, stopped while stabilizing threads",
3109 target_pid_to_str (ptid_of (current_thread
)).c_str ());
3111 return ptid_of (current_thread
);
3117 /* Check whether GDB would be interested in this event. */
3119 /* Check if GDB is interested in this syscall. */
3121 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3122 && !gdb_catch_this_syscall (event_child
))
3124 threads_debug_printf ("Ignored syscall for LWP %ld.",
3125 lwpid_of (current_thread
));
3127 resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
3129 return ignore_event (ourstatus
);
3132 /* If GDB is not interested in this signal, don't stop other
3133 threads, and don't report it to GDB. Just resume the inferior
3134 right away. We do this for threading-related signals as well as
3135 any that GDB specifically requested we ignore. But never ignore
3136 SIGSTOP if we sent it ourselves, and do not ignore signals when
3137 stepping - they may require special handling to skip the signal
3138 handler. Also never ignore signals that could be caused by a
3141 && current_thread
->last_resume_kind
!= resume_step
3143 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3144 (current_process ()->priv
->thread_db
!= NULL
3145 && (WSTOPSIG (w
) == __SIGRTMIN
3146 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3149 (cs
.pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3150 && !(WSTOPSIG (w
) == SIGSTOP
3151 && current_thread
->last_resume_kind
== resume_stop
)
3152 && !linux_wstatus_maybe_breakpoint (w
))))
3154 siginfo_t info
, *info_p
;
3156 threads_debug_printf ("Ignored signal %d for LWP %ld.",
3157 WSTOPSIG (w
), lwpid_of (current_thread
));
3159 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3160 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3165 if (step_over_finished
)
3167 /* We cancelled this thread's step-over above. We still
3168 need to unsuspend all other LWPs, and set them back
3169 running again while the signal handler runs. */
3170 unsuspend_all_lwps (event_child
);
3172 /* Enqueue the pending signal info so that proceed_all_lwps
3174 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3176 proceed_all_lwps ();
3180 resume_one_lwp (event_child
, event_child
->stepping
,
3181 WSTOPSIG (w
), info_p
);
3184 return ignore_event (ourstatus
);
3187 /* Note that all addresses are always "out of the step range" when
3188 there's no range to begin with. */
3189 in_step_range
= lwp_in_step_range (event_child
);
3191 /* If GDB wanted this thread to single step, and the thread is out
3192 of the step range, we always want to report the SIGTRAP, and let
3193 GDB handle it. Watchpoints should always be reported. So should
3194 signals we can't explain. A SIGTRAP we can't explain could be a
3195 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3196 do, we're be able to handle GDB breakpoints on top of internal
3197 breakpoints, by handling the internal breakpoint and still
3198 reporting the event to GDB. If we don't, we're out of luck, GDB
3199 won't see the breakpoint hit. If we see a single-step event but
3200 the thread should be continuing, don't pass the trap to gdb.
3201 That indicates that we had previously finished a single-step but
3202 left the single-step pending -- see
3203 complete_ongoing_step_over. */
3204 report_to_gdb
= (!maybe_internal_trap
3205 || (current_thread
->last_resume_kind
== resume_step
3207 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3209 && !bp_explains_trap
3211 && !step_over_finished
3212 && !(current_thread
->last_resume_kind
== resume_continue
3213 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3214 || (gdb_breakpoint_here (event_child
->stop_pc
)
3215 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3216 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3217 || event_child
->waitstatus
.kind () != TARGET_WAITKIND_IGNORE
);
3219 run_breakpoint_commands (event_child
->stop_pc
);
3221 /* We found no reason GDB would want us to stop. We either hit one
3222 of our own breakpoints, or finished an internal step GDB
3223 shouldn't know about. */
3226 if (bp_explains_trap
)
3227 threads_debug_printf ("Hit a gdbserver breakpoint.");
3229 if (step_over_finished
)
3230 threads_debug_printf ("Step-over finished.");
3233 threads_debug_printf ("Tracepoint event.");
3235 if (lwp_in_step_range (event_child
))
3236 threads_debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).",
3237 paddress (event_child
->stop_pc
),
3238 paddress (event_child
->step_range_start
),
3239 paddress (event_child
->step_range_end
));
3241 /* We're not reporting this breakpoint to GDB, so apply the
3242 decr_pc_after_break adjustment to the inferior's regcache
3245 if (low_supports_breakpoints ())
3247 struct regcache
*regcache
3248 = get_thread_regcache (current_thread
, 1);
3249 low_set_pc (regcache
, event_child
->stop_pc
);
3252 if (step_over_finished
)
3254 /* If we have finished stepping over a breakpoint, we've
3255 stopped and suspended all LWPs momentarily except the
3256 stepping one. This is where we resume them all again.
3257 We're going to keep waiting, so use proceed, which
3258 handles stepping over the next breakpoint. */
3259 unsuspend_all_lwps (event_child
);
3263 /* Remove the single-step breakpoints if any. Note that
3264 there isn't single-step breakpoint if we finished stepping
3266 if (supports_software_single_step ()
3267 && has_single_step_breakpoints (current_thread
))
3269 stop_all_lwps (0, event_child
);
3270 delete_single_step_breakpoints (current_thread
);
3271 unstop_all_lwps (0, event_child
);
3275 threads_debug_printf ("proceeding all threads.");
3277 proceed_all_lwps ();
3279 return ignore_event (ourstatus
);
3284 if (event_child
->waitstatus
.kind () != TARGET_WAITKIND_IGNORE
)
3285 threads_debug_printf ("LWP %ld: extended event with waitstatus %s",
3286 lwpid_of (get_lwp_thread (event_child
)),
3287 event_child
->waitstatus
.to_string ().c_str ());
3289 if (current_thread
->last_resume_kind
== resume_step
)
3291 if (event_child
->step_range_start
== event_child
->step_range_end
)
3292 threads_debug_printf
3293 ("GDB wanted to single-step, reporting event.");
3294 else if (!lwp_in_step_range (event_child
))
3295 threads_debug_printf ("Out of step range, reporting event.");
3298 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3299 threads_debug_printf ("Stopped by watchpoint.");
3300 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3301 threads_debug_printf ("Stopped by GDB breakpoint.");
3304 threads_debug_printf ("Hit a non-gdbserver trap event.");
3306 /* Alright, we're going to report a stop. */
3308 /* Remove single-step breakpoints. */
3309 if (supports_software_single_step ())
3311 /* Remove single-step breakpoints or not. It it is true, stop all
3312 lwps, so that other threads won't hit the breakpoint in the
3314 int remove_single_step_breakpoints_p
= 0;
3318 remove_single_step_breakpoints_p
3319 = has_single_step_breakpoints (current_thread
);
3323 /* In all-stop, a stop reply cancels all previous resume
3324 requests. Delete all single-step breakpoints. */
3326 find_thread ([&] (thread_info
*thread
) {
3327 if (has_single_step_breakpoints (thread
))
3329 remove_single_step_breakpoints_p
= 1;
3337 if (remove_single_step_breakpoints_p
)
3339 /* If we remove single-step breakpoints from memory, stop all lwps,
3340 so that other threads won't hit the breakpoint in the staled
3342 stop_all_lwps (0, event_child
);
3346 gdb_assert (has_single_step_breakpoints (current_thread
));
3347 delete_single_step_breakpoints (current_thread
);
3351 for_each_thread ([] (thread_info
*thread
){
3352 if (has_single_step_breakpoints (thread
))
3353 delete_single_step_breakpoints (thread
);
3357 unstop_all_lwps (0, event_child
);
3361 if (!stabilizing_threads
)
3363 /* In all-stop, stop all threads. */
3365 stop_all_lwps (0, NULL
);
3367 if (step_over_finished
)
3371 /* If we were doing a step-over, all other threads but
3372 the stepping one had been paused in start_step_over,
3373 with their suspend counts incremented. We don't want
3374 to do a full unstop/unpause, because we're in
3375 all-stop mode (so we want threads stopped), but we
3376 still need to unsuspend the other threads, to
3377 decrement their `suspended' count back. */
3378 unsuspend_all_lwps (event_child
);
3382 /* If we just finished a step-over, then all threads had
3383 been momentarily paused. In all-stop, that's fine,
3384 we want threads stopped by now anyway. In non-stop,
3385 we need to re-resume threads that GDB wanted to be
3387 unstop_all_lwps (1, event_child
);
3391 /* If we're not waiting for a specific LWP, choose an event LWP
3392 from among those that have had events. Giving equal priority
3393 to all LWPs that have had events helps prevent
3395 if (ptid
== minus_one_ptid
)
3397 event_child
->status_pending_p
= 1;
3398 event_child
->status_pending
= w
;
3400 select_event_lwp (&event_child
);
3402 /* current_thread and event_child must stay in sync. */
3403 switch_to_thread (get_lwp_thread (event_child
));
3405 event_child
->status_pending_p
= 0;
3406 w
= event_child
->status_pending
;
3410 /* Stabilize threads (move out of jump pads). */
3412 target_stabilize_threads ();
3416 /* If we just finished a step-over, then all threads had been
3417 momentarily paused. In all-stop, that's fine, we want
3418 threads stopped by now anyway. In non-stop, we need to
3419 re-resume threads that GDB wanted to be running. */
3420 if (step_over_finished
)
3421 unstop_all_lwps (1, event_child
);
3424 if (event_child
->waitstatus
.kind () != TARGET_WAITKIND_IGNORE
)
3426 /* If the reported event is an exit, fork, vfork or exec, let
3429 /* Break the unreported fork relationship chain. */
3430 if (event_child
->waitstatus
.kind () == TARGET_WAITKIND_FORKED
3431 || event_child
->waitstatus
.kind () == TARGET_WAITKIND_VFORKED
)
3433 event_child
->fork_relative
->fork_relative
= NULL
;
3434 event_child
->fork_relative
= NULL
;
3437 *ourstatus
= event_child
->waitstatus
;
3438 /* Clear the event lwp's waitstatus since we handled it already. */
3439 event_child
->waitstatus
.set_ignore ();
3443 /* The actual stop signal is overwritten below. */
3444 ourstatus
->set_stopped (GDB_SIGNAL_0
);
3447 /* Now that we've selected our final event LWP, un-adjust its PC if
3448 it was a software breakpoint, and the client doesn't know we can
3449 adjust the breakpoint ourselves. */
3450 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3451 && !cs
.swbreak_feature
)
3453 int decr_pc
= low_decr_pc_after_break ();
3457 struct regcache
*regcache
3458 = get_thread_regcache (current_thread
, 1);
3459 low_set_pc (regcache
, event_child
->stop_pc
+ decr_pc
);
3463 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3467 get_syscall_trapinfo (event_child
, &syscall_number
);
3468 if (event_child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
)
3469 ourstatus
->set_syscall_entry (syscall_number
);
3470 else if (event_child
->syscall_state
== TARGET_WAITKIND_SYSCALL_RETURN
)
3471 ourstatus
->set_syscall_return (syscall_number
);
3473 gdb_assert_not_reached ("unexpected syscall state");
3475 else if (current_thread
->last_resume_kind
== resume_stop
3476 && WSTOPSIG (w
) == SIGSTOP
)
3478 /* A thread that has been requested to stop by GDB with vCont;t,
3479 and it stopped cleanly, so report as SIG0. The use of
3480 SIGSTOP is an implementation detail. */
3481 ourstatus
->set_stopped (GDB_SIGNAL_0
);
3483 else if (current_thread
->last_resume_kind
== resume_stop
3484 && WSTOPSIG (w
) != SIGSTOP
)
3486 /* A thread that has been requested to stop by GDB with vCont;t,
3487 but, it stopped for other reasons. */
3488 ourstatus
->set_stopped (gdb_signal_from_host (WSTOPSIG (w
)));
3490 else if (ourstatus
->kind () == TARGET_WAITKIND_STOPPED
)
3491 ourstatus
->set_stopped (gdb_signal_from_host (WSTOPSIG (w
)));
3493 gdb_assert (step_over_bkpt
== null_ptid
);
3495 threads_debug_printf ("ret = %s, %d, %d",
3496 target_pid_to_str (ptid_of (current_thread
)).c_str (),
3497 ourstatus
->kind (), ourstatus
->sig ());
3499 if (ourstatus
->kind () == TARGET_WAITKIND_EXITED
)
3500 return filter_exit_event (event_child
, ourstatus
);
3502 return ptid_of (current_thread
);
3505 /* Get rid of any pending event in the pipe. */
3507 async_file_flush (void)
3513 ret
= read (linux_event_pipe
[0], &buf
, 1);
3514 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3517 /* Put something in the pipe, so the event loop wakes up. */
3519 async_file_mark (void)
3523 async_file_flush ();
3526 ret
= write (linux_event_pipe
[1], "+", 1);
3527 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3529 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3530 be awakened anyway. */
3534 linux_process_target::wait (ptid_t ptid
,
3535 target_waitstatus
*ourstatus
,
3536 target_wait_flags target_options
)
3540 /* Flush the async file first. */
3541 if (target_is_async_p ())
3542 async_file_flush ();
3546 event_ptid
= wait_1 (ptid
, ourstatus
, target_options
);
3548 while ((target_options
& TARGET_WNOHANG
) == 0
3549 && event_ptid
== null_ptid
3550 && ourstatus
->kind () == TARGET_WAITKIND_IGNORE
);
3552 /* If at least one stop was reported, there may be more. A single
3553 SIGCHLD can signal more than one child stop. */
3554 if (target_is_async_p ()
3555 && (target_options
& TARGET_WNOHANG
) != 0
3556 && event_ptid
!= null_ptid
)
3562 /* Send a signal to an LWP. */
3565 kill_lwp (unsigned long lwpid
, int signo
)
3570 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3571 if (errno
== ENOSYS
)
3573 /* If tkill fails, then we are not using nptl threads, a
3574 configuration we no longer support. */
3575 perror_with_name (("tkill"));
3581 linux_stop_lwp (struct lwp_info
*lwp
)
3587 send_sigstop (struct lwp_info
*lwp
)
3591 pid
= lwpid_of (get_lwp_thread (lwp
));
3593 /* If we already have a pending stop signal for this process, don't
3595 if (lwp
->stop_expected
)
3597 threads_debug_printf ("Have pending sigstop for lwp %d", pid
);
3602 threads_debug_printf ("Sending sigstop to lwp %d", pid
);
3604 lwp
->stop_expected
= 1;
3605 kill_lwp (pid
, SIGSTOP
);
3609 send_sigstop (thread_info
*thread
, lwp_info
*except
)
3611 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3613 /* Ignore EXCEPT. */
3623 /* Increment the suspend count of an LWP, and stop it, if not stopped
3626 suspend_and_send_sigstop (thread_info
*thread
, lwp_info
*except
)
3628 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3630 /* Ignore EXCEPT. */
3634 lwp_suspended_inc (lwp
);
3636 send_sigstop (thread
, except
);
3640 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3642 /* Store the exit status for later. */
3643 lwp
->status_pending_p
= 1;
3644 lwp
->status_pending
= wstat
;
3646 /* Store in waitstatus as well, as there's nothing else to process
3648 if (WIFEXITED (wstat
))
3649 lwp
->waitstatus
.set_exited (WEXITSTATUS (wstat
));
3650 else if (WIFSIGNALED (wstat
))
3651 lwp
->waitstatus
.set_signalled (gdb_signal_from_host (WTERMSIG (wstat
)));
3653 /* Prevent trying to stop it. */
3656 /* No further stops are expected from a dead lwp. */
3657 lwp
->stop_expected
= 0;
3660 /* Return true if LWP has exited already, and has a pending exit event
3661 to report to GDB. */
3664 lwp_is_marked_dead (struct lwp_info
*lwp
)
3666 return (lwp
->status_pending_p
3667 && (WIFEXITED (lwp
->status_pending
)
3668 || WIFSIGNALED (lwp
->status_pending
)));
3672 linux_process_target::wait_for_sigstop ()
3674 struct thread_info
*saved_thread
;
3679 saved_thread
= current_thread
;
3680 if (saved_thread
!= NULL
)
3681 saved_tid
= saved_thread
->id
;
3683 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3685 scoped_restore_current_thread restore_thread
;
3687 threads_debug_printf ("pulling events");
3689 /* Passing NULL_PTID as filter indicates we want all events to be
3690 left pending. Eventually this returns when there are no
3691 unwaited-for children left. */
3692 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
, __WALL
);
3693 gdb_assert (ret
== -1);
3695 if (saved_thread
== NULL
|| mythread_alive (saved_tid
))
3699 threads_debug_printf ("Previously current thread died.");
3701 /* We can't change the current inferior behind GDB's back,
3702 otherwise, a subsequent command may apply to the wrong
3704 restore_thread
.dont_restore ();
3705 switch_to_thread (nullptr);
3710 linux_process_target::stuck_in_jump_pad (thread_info
*thread
)
3712 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3714 if (lwp
->suspended
!= 0)
3716 internal_error (__FILE__
, __LINE__
,
3717 "LWP %ld is suspended, suspended=%d\n",
3718 lwpid_of (thread
), lwp
->suspended
);
3720 gdb_assert (lwp
->stopped
);
3722 /* Allow debugging the jump pad, gdb_collect, etc.. */
3723 return (supports_fast_tracepoints ()
3724 && agent_loaded_p ()
3725 && (gdb_breakpoint_here (lwp
->stop_pc
)
3726 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3727 || thread
->last_resume_kind
== resume_step
)
3728 && (linux_fast_tracepoint_collecting (lwp
, NULL
)
3729 != fast_tpoint_collect_result::not_collecting
));
3733 linux_process_target::move_out_of_jump_pad (thread_info
*thread
)
3735 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3738 if (lwp
->suspended
!= 0)
3740 internal_error (__FILE__
, __LINE__
,
3741 "LWP %ld is suspended, suspended=%d\n",
3742 lwpid_of (thread
), lwp
->suspended
);
3744 gdb_assert (lwp
->stopped
);
3746 /* For gdb_breakpoint_here. */
3747 scoped_restore_current_thread restore_thread
;
3748 switch_to_thread (thread
);
3750 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3752 /* Allow debugging the jump pad, gdb_collect, etc. */
3753 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3754 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3755 && thread
->last_resume_kind
!= resume_step
3756 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3758 threads_debug_printf ("LWP %ld needs stabilizing (in jump pad)",
3763 lwp
->status_pending_p
= 0;
3764 enqueue_one_deferred_signal (lwp
, wstat
);
3766 threads_debug_printf ("Signal %d for LWP %ld deferred (in jump pad",
3767 WSTOPSIG (*wstat
), lwpid_of (thread
));
3770 resume_one_lwp (lwp
, 0, 0, NULL
);
3773 lwp_suspended_inc (lwp
);
3777 lwp_running (thread_info
*thread
)
3779 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3781 if (lwp_is_marked_dead (lwp
))
3784 return !lwp
->stopped
;
3788 linux_process_target::stop_all_lwps (int suspend
, lwp_info
*except
)
3790 /* Should not be called recursively. */
3791 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3793 THREADS_SCOPED_DEBUG_ENTER_EXIT
;
3795 threads_debug_printf
3796 ("%s, except=%s", suspend
? "stop-and-suspend" : "stop",
3798 ? target_pid_to_str (ptid_of (get_lwp_thread (except
))).c_str ()
3801 stopping_threads
= (suspend
3802 ? STOPPING_AND_SUSPENDING_THREADS
3803 : STOPPING_THREADS
);
3806 for_each_thread ([&] (thread_info
*thread
)
3808 suspend_and_send_sigstop (thread
, except
);
3811 for_each_thread ([&] (thread_info
*thread
)
3813 send_sigstop (thread
, except
);
3816 wait_for_sigstop ();
3817 stopping_threads
= NOT_STOPPING_THREADS
;
3819 threads_debug_printf ("setting stopping_threads back to !stopping");
3822 /* Enqueue one signal in the chain of signals which need to be
3823 delivered to this process on next resume. */
3826 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
3828 lwp
->pending_signals
.emplace_back (signal
);
3829 if (info
== nullptr)
3830 memset (&lwp
->pending_signals
.back ().info
, 0, sizeof (siginfo_t
));
3832 lwp
->pending_signals
.back ().info
= *info
;
3836 linux_process_target::install_software_single_step_breakpoints (lwp_info
*lwp
)
3838 struct thread_info
*thread
= get_lwp_thread (lwp
);
3839 struct regcache
*regcache
= get_thread_regcache (thread
, 1);
3841 scoped_restore_current_thread restore_thread
;
3843 switch_to_thread (thread
);
3844 std::vector
<CORE_ADDR
> next_pcs
= low_get_next_pcs (regcache
);
3846 for (CORE_ADDR pc
: next_pcs
)
3847 set_single_step_breakpoint (pc
, current_ptid
);
3851 linux_process_target::single_step (lwp_info
* lwp
)
3855 if (supports_hardware_single_step ())
3859 else if (supports_software_single_step ())
3861 install_software_single_step_breakpoints (lwp
);
3865 threads_debug_printf ("stepping is not implemented on this target");
3870 /* The signal can be delivered to the inferior if we are not trying to
3871 finish a fast tracepoint collect. Since signal can be delivered in
3872 the step-over, the program may go to signal handler and trap again
3873 after return from the signal handler. We can live with the spurious
3877 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
3879 return (lwp
->collecting_fast_tracepoint
3880 == fast_tpoint_collect_result::not_collecting
);
3884 linux_process_target::resume_one_lwp_throw (lwp_info
*lwp
, int step
,
3885 int signal
, siginfo_t
*info
)
3887 struct thread_info
*thread
= get_lwp_thread (lwp
);
3889 struct process_info
*proc
= get_thread_process (thread
);
3891 /* Note that target description may not be initialised
3892 (proc->tdesc == NULL) at this point because the program hasn't
3893 stopped at the first instruction yet. It means GDBserver skips
3894 the extra traps from the wrapper program (see option --wrapper).
3895 Code in this function that requires register access should be
3896 guarded by proc->tdesc == NULL or something else. */
3898 if (lwp
->stopped
== 0)
3901 gdb_assert (lwp
->waitstatus
.kind () == TARGET_WAITKIND_IGNORE
);
3903 fast_tpoint_collect_result fast_tp_collecting
3904 = lwp
->collecting_fast_tracepoint
;
3906 gdb_assert (!stabilizing_threads
3907 || (fast_tp_collecting
3908 != fast_tpoint_collect_result::not_collecting
));
3910 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3911 user used the "jump" command, or "set $pc = foo"). */
3912 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
3914 /* Collecting 'while-stepping' actions doesn't make sense
3916 release_while_stepping_state_list (thread
);
3919 /* If we have pending signals or status, and a new signal, enqueue the
3920 signal. Also enqueue the signal if it can't be delivered to the
3921 inferior right now. */
3923 && (lwp
->status_pending_p
3924 || !lwp
->pending_signals
.empty ()
3925 || !lwp_signal_can_be_delivered (lwp
)))
3927 enqueue_pending_signal (lwp
, signal
, info
);
3929 /* Postpone any pending signal. It was enqueued above. */
3933 if (lwp
->status_pending_p
)
3935 threads_debug_printf
3936 ("Not resuming lwp %ld (%s, stop %s); has pending status",
3937 lwpid_of (thread
), step
? "step" : "continue",
3938 lwp
->stop_expected
? "expected" : "not expected");
3942 scoped_restore_current_thread restore_thread
;
3943 switch_to_thread (thread
);
3945 /* This bit needs some thinking about. If we get a signal that
3946 we must report while a single-step reinsert is still pending,
3947 we often end up resuming the thread. It might be better to
3948 (ew) allow a stack of pending events; then we could be sure that
3949 the reinsert happened right away and not lose any signals.
3951 Making this stack would also shrink the window in which breakpoints are
3952 uninserted (see comment in linux_wait_for_lwp) but not enough for
3953 complete correctness, so it won't solve that problem. It may be
3954 worthwhile just to solve this one, however. */
3955 if (lwp
->bp_reinsert
!= 0)
3957 threads_debug_printf (" pending reinsert at 0x%s",
3958 paddress (lwp
->bp_reinsert
));
3960 if (supports_hardware_single_step ())
3962 if (fast_tp_collecting
== fast_tpoint_collect_result::not_collecting
)
3965 warning ("BAD - reinserting but not stepping.");
3967 warning ("BAD - reinserting and suspended(%d).",
3972 step
= maybe_hw_step (thread
);
3975 if (fast_tp_collecting
== fast_tpoint_collect_result::before_insn
)
3976 threads_debug_printf
3977 ("lwp %ld wants to get out of fast tracepoint jump pad "
3978 "(exit-jump-pad-bkpt)", lwpid_of (thread
));
3980 else if (fast_tp_collecting
== fast_tpoint_collect_result::at_insn
)
3982 threads_debug_printf
3983 ("lwp %ld wants to get out of fast tracepoint jump pad single-stepping",
3986 if (supports_hardware_single_step ())
3990 internal_error (__FILE__
, __LINE__
,
3991 "moving out of jump pad single-stepping"
3992 " not implemented on this target");
3996 /* If we have while-stepping actions in this thread set it stepping.
3997 If we have a signal to deliver, it may or may not be set to
3998 SIG_IGN, we don't know. Assume so, and allow collecting
3999 while-stepping into a signal handler. A possible smart thing to
4000 do would be to set an internal breakpoint at the signal return
4001 address, continue, and carry on catching this while-stepping
4002 action only when that breakpoint is hit. A future
4004 if (thread
->while_stepping
!= NULL
)
4006 threads_debug_printf
4007 ("lwp %ld has a while-stepping action -> forcing step.",
4010 step
= single_step (lwp
);
4013 if (proc
->tdesc
!= NULL
&& low_supports_breakpoints ())
4015 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4017 lwp
->stop_pc
= low_get_pc (regcache
);
4019 threads_debug_printf (" %s from pc 0x%lx", step
? "step" : "continue",
4020 (long) lwp
->stop_pc
);
4023 /* If we have pending signals, consume one if it can be delivered to
4025 if (!lwp
->pending_signals
.empty () && lwp_signal_can_be_delivered (lwp
))
4027 const pending_signal
&p_sig
= lwp
->pending_signals
.front ();
4029 signal
= p_sig
.signal
;
4030 if (p_sig
.info
.si_signo
!= 0)
4031 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4034 lwp
->pending_signals
.pop_front ();
4037 threads_debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)",
4038 lwpid_of (thread
), step
? "step" : "continue", signal
,
4039 lwp
->stop_expected
? "expected" : "not expected");
4041 low_prepare_to_resume (lwp
);
4043 regcache_invalidate_thread (thread
);
4045 lwp
->stepping
= step
;
4047 ptrace_request
= PTRACE_SINGLESTEP
;
4048 else if (gdb_catching_syscalls_p (lwp
))
4049 ptrace_request
= PTRACE_SYSCALL
;
4051 ptrace_request
= PTRACE_CONT
;
4052 ptrace (ptrace_request
,
4054 (PTRACE_TYPE_ARG3
) 0,
4055 /* Coerce to a uintptr_t first to avoid potential gcc warning
4056 of coercing an 8 byte integer to a 4 byte pointer. */
4057 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4060 perror_with_name ("resuming thread");
4062 /* Successfully resumed. Clear state that no longer makes sense,
4063 and mark the LWP as running. Must not do this before resuming
4064 otherwise if that fails other code will be confused. E.g., we'd
4065 later try to stop the LWP and hang forever waiting for a stop
4066 status. Note that we must not throw after this is cleared,
4067 otherwise handle_zombie_lwp_error would get confused. */
4069 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4073 linux_process_target::low_prepare_to_resume (lwp_info
*lwp
)
4078 /* Called when we try to resume a stopped LWP and that errors out. If
4079 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4080 or about to become), discard the error, clear any pending status
4081 the LWP may have, and return true (we'll collect the exit status
4082 soon enough). Otherwise, return false. */
4085 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4087 struct thread_info
*thread
= get_lwp_thread (lp
);
4089 /* If we get an error after resuming the LWP successfully, we'd
4090 confuse !T state for the LWP being gone. */
4091 gdb_assert (lp
->stopped
);
4093 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4094 because even if ptrace failed with ESRCH, the tracee may be "not
4095 yet fully dead", but already refusing ptrace requests. In that
4096 case the tracee has 'R (Running)' state for a little bit
4097 (observed in Linux 3.18). See also the note on ESRCH in the
4098 ptrace(2) man page. Instead, check whether the LWP has any state
4099 other than ptrace-stopped. */
4101 /* Don't assume anything if /proc/PID/status can't be read. */
4102 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4104 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4105 lp
->status_pending_p
= 0;
4112 linux_process_target::resume_one_lwp (lwp_info
*lwp
, int step
, int signal
,
4117 resume_one_lwp_throw (lwp
, step
, signal
, info
);
4119 catch (const gdb_exception_error
&ex
)
4121 if (!check_ptrace_stopped_lwp_gone (lwp
))
4126 /* This function is called once per thread via for_each_thread.
4127 We look up which resume request applies to THREAD and mark it with a
4128 pointer to the appropriate resume request.
4130 This algorithm is O(threads * resume elements), but resume elements
4131 is small (and will remain small at least until GDB supports thread
4135 linux_set_resume_request (thread_info
*thread
, thread_resume
*resume
, size_t n
)
4137 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4139 for (int ndx
= 0; ndx
< n
; ndx
++)
4141 ptid_t ptid
= resume
[ndx
].thread
;
4142 if (ptid
== minus_one_ptid
4143 || ptid
== thread
->id
4144 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4146 || (ptid
.pid () == pid_of (thread
)
4148 || ptid
.lwp () == -1)))
4150 if (resume
[ndx
].kind
== resume_stop
4151 && thread
->last_resume_kind
== resume_stop
)
4153 threads_debug_printf
4154 ("already %s LWP %ld at GDB's request",
4155 (thread
->last_status
.kind () == TARGET_WAITKIND_STOPPED
4156 ? "stopped" : "stopping"),
4162 /* Ignore (wildcard) resume requests for already-resumed
4164 if (resume
[ndx
].kind
!= resume_stop
4165 && thread
->last_resume_kind
!= resume_stop
)
4167 threads_debug_printf
4168 ("already %s LWP %ld at GDB's request",
4169 (thread
->last_resume_kind
== resume_step
4170 ? "stepping" : "continuing"),
4175 /* Don't let wildcard resumes resume fork children that GDB
4176 does not yet know are new fork children. */
4177 if (lwp
->fork_relative
!= NULL
)
4179 struct lwp_info
*rel
= lwp
->fork_relative
;
4181 if (rel
->status_pending_p
4182 && (rel
->waitstatus
.kind () == TARGET_WAITKIND_FORKED
4183 || rel
->waitstatus
.kind () == TARGET_WAITKIND_VFORKED
))
4185 threads_debug_printf
4186 ("not resuming LWP %ld: has queued stop reply",
4192 /* If the thread has a pending event that has already been
4193 reported to GDBserver core, but GDB has not pulled the
4194 event out of the vStopped queue yet, likewise, ignore the
4195 (wildcard) resume request. */
4196 if (in_queued_stop_replies (thread
->id
))
4198 threads_debug_printf
4199 ("not resuming LWP %ld: has queued stop reply",
4204 lwp
->resume
= &resume
[ndx
];
4205 thread
->last_resume_kind
= lwp
->resume
->kind
;
4207 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4208 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4210 /* If we had a deferred signal to report, dequeue one now.
4211 This can happen if LWP gets more than one signal while
4212 trying to get out of a jump pad. */
4214 && !lwp
->status_pending_p
4215 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4217 lwp
->status_pending_p
= 1;
4219 threads_debug_printf
4220 ("Dequeueing deferred signal %d for LWP %ld, "
4221 "leaving status pending.",
4222 WSTOPSIG (lwp
->status_pending
),
4230 /* No resume action for this thread. */
4235 linux_process_target::resume_status_pending (thread_info
*thread
)
4237 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4239 /* LWPs which will not be resumed are not interesting, because
4240 we might not wait for them next time through linux_wait. */
4241 if (lwp
->resume
== NULL
)
4244 return thread_still_has_status_pending (thread
);
4248 linux_process_target::thread_needs_step_over (thread_info
*thread
)
4250 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4252 struct process_info
*proc
= get_thread_process (thread
);
4254 /* GDBserver is skipping the extra traps from the wrapper program,
4255 don't have to do step over. */
4256 if (proc
->tdesc
== NULL
)
4259 /* LWPs which will not be resumed are not interesting, because we
4260 might not wait for them next time through linux_wait. */
4264 threads_debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped",
4269 if (thread
->last_resume_kind
== resume_stop
)
4271 threads_debug_printf
4272 ("Need step over [LWP %ld]? Ignoring, should remain stopped",
4277 gdb_assert (lwp
->suspended
>= 0);
4281 threads_debug_printf ("Need step over [LWP %ld]? Ignoring, suspended",
4286 if (lwp
->status_pending_p
)
4288 threads_debug_printf
4289 ("Need step over [LWP %ld]? Ignoring, has pending status.",
4294 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4298 /* If the PC has changed since we stopped, then don't do anything,
4299 and let the breakpoint/tracepoint be hit. This happens if, for
4300 instance, GDB handled the decr_pc_after_break subtraction itself,
4301 GDB is OOL stepping this thread, or the user has issued a "jump"
4302 command, or poked thread's registers herself. */
4303 if (pc
!= lwp
->stop_pc
)
4305 threads_debug_printf
4306 ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4307 "Old stop_pc was 0x%s, PC is now 0x%s", lwpid_of (thread
),
4308 paddress (lwp
->stop_pc
), paddress (pc
));
4312 /* On software single step target, resume the inferior with signal
4313 rather than stepping over. */
4314 if (supports_software_single_step ()
4315 && !lwp
->pending_signals
.empty ()
4316 && lwp_signal_can_be_delivered (lwp
))
4318 threads_debug_printf
4319 ("Need step over [LWP %ld]? Ignoring, has pending signals.",
4325 scoped_restore_current_thread restore_thread
;
4326 switch_to_thread (thread
);
4328 /* We can only step over breakpoints we know about. */
4329 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4331 /* Don't step over a breakpoint that GDB expects to hit
4332 though. If the condition is being evaluated on the target's side
4333 and it evaluate to false, step over this breakpoint as well. */
4334 if (gdb_breakpoint_here (pc
)
4335 && gdb_condition_true_at_breakpoint (pc
)
4336 && gdb_no_commands_at_breakpoint (pc
))
4338 threads_debug_printf ("Need step over [LWP %ld]? yes, but found"
4339 " GDB breakpoint at 0x%s; skipping step over",
4340 lwpid_of (thread
), paddress (pc
));
4346 threads_debug_printf ("Need step over [LWP %ld]? yes, "
4347 "found breakpoint at 0x%s",
4348 lwpid_of (thread
), paddress (pc
));
4350 /* We've found an lwp that needs stepping over --- return 1 so
4351 that find_thread stops looking. */
4356 threads_debug_printf
4357 ("Need step over [LWP %ld]? No, no breakpoint found at 0x%s",
4358 lwpid_of (thread
), paddress (pc
));
4364 linux_process_target::start_step_over (lwp_info
*lwp
)
4366 struct thread_info
*thread
= get_lwp_thread (lwp
);
4369 threads_debug_printf ("Starting step-over on LWP %ld. Stopping all threads",
4372 stop_all_lwps (1, lwp
);
4374 if (lwp
->suspended
!= 0)
4376 internal_error (__FILE__
, __LINE__
,
4377 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4381 threads_debug_printf ("Done stopping all threads for step-over.");
4383 /* Note, we should always reach here with an already adjusted PC,
4384 either by GDB (if we're resuming due to GDB's request), or by our
4385 caller, if we just finished handling an internal breakpoint GDB
4386 shouldn't care about. */
4391 scoped_restore_current_thread restore_thread
;
4392 switch_to_thread (thread
);
4394 lwp
->bp_reinsert
= pc
;
4395 uninsert_breakpoints_at (pc
);
4396 uninsert_fast_tracepoint_jumps_at (pc
);
4398 step
= single_step (lwp
);
4401 resume_one_lwp (lwp
, step
, 0, NULL
);
4403 /* Require next event from this LWP. */
4404 step_over_bkpt
= thread
->id
;
4408 linux_process_target::finish_step_over (lwp_info
*lwp
)
4410 if (lwp
->bp_reinsert
!= 0)
4412 scoped_restore_current_thread restore_thread
;
4414 threads_debug_printf ("Finished step over.");
4416 switch_to_thread (get_lwp_thread (lwp
));
4418 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4419 may be no breakpoint to reinsert there by now. */
4420 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4421 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4423 lwp
->bp_reinsert
= 0;
4425 /* Delete any single-step breakpoints. No longer needed. We
4426 don't have to worry about other threads hitting this trap,
4427 and later not being able to explain it, because we were
4428 stepping over a breakpoint, and we hold all threads but
4429 LWP stopped while doing that. */
4430 if (!supports_hardware_single_step ())
4432 gdb_assert (has_single_step_breakpoints (current_thread
));
4433 delete_single_step_breakpoints (current_thread
);
4436 step_over_bkpt
= null_ptid
;
4444 linux_process_target::complete_ongoing_step_over ()
4446 if (step_over_bkpt
!= null_ptid
)
4448 struct lwp_info
*lwp
;
4452 threads_debug_printf ("detach: step over in progress, finish it first");
4454 /* Passing NULL_PTID as filter indicates we want all events to
4455 be left pending. Eventually this returns when there are no
4456 unwaited-for children left. */
4457 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
,
4459 gdb_assert (ret
== -1);
4461 lwp
= find_lwp_pid (step_over_bkpt
);
4464 finish_step_over (lwp
);
4466 /* If we got our step SIGTRAP, don't leave it pending,
4467 otherwise we would report it to GDB as a spurious
4469 gdb_assert (lwp
->status_pending_p
);
4470 if (WIFSTOPPED (lwp
->status_pending
)
4471 && WSTOPSIG (lwp
->status_pending
) == SIGTRAP
)
4473 thread_info
*thread
= get_lwp_thread (lwp
);
4474 if (thread
->last_resume_kind
!= resume_step
)
4476 threads_debug_printf ("detach: discard step-over SIGTRAP");
4478 lwp
->status_pending_p
= 0;
4479 lwp
->status_pending
= 0;
4480 resume_one_lwp (lwp
, lwp
->stepping
, 0, NULL
);
4483 threads_debug_printf
4484 ("detach: resume_step, not discarding step-over SIGTRAP");
4487 step_over_bkpt
= null_ptid
;
4488 unsuspend_all_lwps (lwp
);
4493 linux_process_target::resume_one_thread (thread_info
*thread
,
4494 bool leave_all_stopped
)
4496 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4499 if (lwp
->resume
== NULL
)
4502 if (lwp
->resume
->kind
== resume_stop
)
4504 threads_debug_printf ("resume_stop request for LWP %ld",
4509 threads_debug_printf ("stopping LWP %ld", lwpid_of (thread
));
4511 /* Stop the thread, and wait for the event asynchronously,
4512 through the event loop. */
4517 threads_debug_printf ("already stopped LWP %ld", lwpid_of (thread
));
4519 /* The LWP may have been stopped in an internal event that
4520 was not meant to be notified back to GDB (e.g., gdbserver
4521 breakpoint), so we should be reporting a stop event in
4524 /* If the thread already has a pending SIGSTOP, this is a
4525 no-op. Otherwise, something later will presumably resume
4526 the thread and this will cause it to cancel any pending
4527 operation, due to last_resume_kind == resume_stop. If
4528 the thread already has a pending status to report, we
4529 will still report it the next time we wait - see
4530 status_pending_p_callback. */
4532 /* If we already have a pending signal to report, then
4533 there's no need to queue a SIGSTOP, as this means we're
4534 midway through moving the LWP out of the jumppad, and we
4535 will report the pending signal as soon as that is
4537 if (lwp
->pending_signals_to_report
.empty ())
4541 /* For stop requests, we're done. */
4543 thread
->last_status
.set_ignore ();
4547 /* If this thread which is about to be resumed has a pending status,
4548 then don't resume it - we can just report the pending status.
4549 Likewise if it is suspended, because e.g., another thread is
4550 stepping past a breakpoint. Make sure to queue any signals that
4551 would otherwise be sent. In all-stop mode, we do this decision
4552 based on if *any* thread has a pending status. If there's a
4553 thread that needs the step-over-breakpoint dance, then don't
4554 resume any other thread but that particular one. */
4555 leave_pending
= (lwp
->suspended
4556 || lwp
->status_pending_p
4557 || leave_all_stopped
);
4559 /* If we have a new signal, enqueue the signal. */
4560 if (lwp
->resume
->sig
!= 0)
4562 siginfo_t info
, *info_p
;
4564 /* If this is the same signal we were previously stopped by,
4565 make sure to queue its siginfo. */
4566 if (WIFSTOPPED (lwp
->last_status
)
4567 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
4568 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
),
4569 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
4574 enqueue_pending_signal (lwp
, lwp
->resume
->sig
, info_p
);
4579 threads_debug_printf ("resuming LWP %ld", lwpid_of (thread
));
4581 proceed_one_lwp (thread
, NULL
);
4584 threads_debug_printf ("leaving LWP %ld stopped", lwpid_of (thread
));
4586 thread
->last_status
.set_ignore ();
4591 linux_process_target::resume (thread_resume
*resume_info
, size_t n
)
4593 struct thread_info
*need_step_over
= NULL
;
4595 THREADS_SCOPED_DEBUG_ENTER_EXIT
;
4597 for_each_thread ([&] (thread_info
*thread
)
4599 linux_set_resume_request (thread
, resume_info
, n
);
4602 /* If there is a thread which would otherwise be resumed, which has
4603 a pending status, then don't resume any threads - we can just
4604 report the pending status. Make sure to queue any signals that
4605 would otherwise be sent. In non-stop mode, we'll apply this
4606 logic to each thread individually. We consume all pending events
4607 before considering to start a step-over (in all-stop). */
4608 bool any_pending
= false;
4610 any_pending
= find_thread ([this] (thread_info
*thread
)
4612 return resume_status_pending (thread
);
4615 /* If there is a thread which would otherwise be resumed, which is
4616 stopped at a breakpoint that needs stepping over, then don't
4617 resume any threads - have it step over the breakpoint with all
4618 other threads stopped, then resume all threads again. Make sure
4619 to queue any signals that would otherwise be delivered or
4621 if (!any_pending
&& low_supports_breakpoints ())
4622 need_step_over
= find_thread ([this] (thread_info
*thread
)
4624 return thread_needs_step_over (thread
);
4627 bool leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4629 if (need_step_over
!= NULL
)
4630 threads_debug_printf ("Not resuming all, need step over");
4631 else if (any_pending
)
4632 threads_debug_printf ("Not resuming, all-stop and found "
4633 "an LWP with pending status");
4635 threads_debug_printf ("Resuming, no pending status or step over needed");
4637 /* Even if we're leaving threads stopped, queue all signals we'd
4638 otherwise deliver. */
4639 for_each_thread ([&] (thread_info
*thread
)
4641 resume_one_thread (thread
, leave_all_stopped
);
4645 start_step_over (get_thread_lwp (need_step_over
));
4647 /* We may have events that were pending that can/should be sent to
4648 the client now. Trigger a linux_wait call. */
4649 if (target_is_async_p ())
4654 linux_process_target::proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
4656 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4662 threads_debug_printf ("lwp %ld", lwpid_of (thread
));
4666 threads_debug_printf (" LWP %ld already running", lwpid_of (thread
));
4670 if (thread
->last_resume_kind
== resume_stop
4671 && thread
->last_status
.kind () != TARGET_WAITKIND_IGNORE
)
4673 threads_debug_printf (" client wants LWP to remain %ld stopped",
4678 if (lwp
->status_pending_p
)
4680 threads_debug_printf (" LWP %ld has pending status, leaving stopped",
4685 gdb_assert (lwp
->suspended
>= 0);
4689 threads_debug_printf (" LWP %ld is suspended", lwpid_of (thread
));
4693 if (thread
->last_resume_kind
== resume_stop
4694 && lwp
->pending_signals_to_report
.empty ()
4695 && (lwp
->collecting_fast_tracepoint
4696 == fast_tpoint_collect_result::not_collecting
))
4698 /* We haven't reported this LWP as stopped yet (otherwise, the
4699 last_status.kind check above would catch it, and we wouldn't
4700 reach here. This LWP may have been momentarily paused by a
4701 stop_all_lwps call while handling for example, another LWP's
4702 step-over. In that case, the pending expected SIGSTOP signal
4703 that was queued at vCont;t handling time will have already
4704 been consumed by wait_for_sigstop, and so we need to requeue
4705 another one here. Note that if the LWP already has a SIGSTOP
4706 pending, this is a no-op. */
4708 threads_debug_printf
4709 ("Client wants LWP %ld to stop. Making sure it has a SIGSTOP pending",
4715 if (thread
->last_resume_kind
== resume_step
)
4717 threads_debug_printf (" stepping LWP %ld, client wants it stepping",
4720 /* If resume_step is requested by GDB, install single-step
4721 breakpoints when the thread is about to be actually resumed if
4722 the single-step breakpoints weren't removed. */
4723 if (supports_software_single_step ()
4724 && !has_single_step_breakpoints (thread
))
4725 install_software_single_step_breakpoints (lwp
);
4727 step
= maybe_hw_step (thread
);
4729 else if (lwp
->bp_reinsert
!= 0)
4731 threads_debug_printf (" stepping LWP %ld, reinsert set",
4734 step
= maybe_hw_step (thread
);
4739 resume_one_lwp (lwp
, step
, 0, NULL
);
4743 linux_process_target::unsuspend_and_proceed_one_lwp (thread_info
*thread
,
4746 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4751 lwp_suspended_decr (lwp
);
4753 proceed_one_lwp (thread
, except
);
4757 linux_process_target::proceed_all_lwps ()
4759 struct thread_info
*need_step_over
;
4761 /* If there is a thread which would otherwise be resumed, which is
4762 stopped at a breakpoint that needs stepping over, then don't
4763 resume any threads - have it step over the breakpoint with all
4764 other threads stopped, then resume all threads again. */
4766 if (low_supports_breakpoints ())
4768 need_step_over
= find_thread ([this] (thread_info
*thread
)
4770 return thread_needs_step_over (thread
);
4773 if (need_step_over
!= NULL
)
4775 threads_debug_printf ("found thread %ld needing a step-over",
4776 lwpid_of (need_step_over
));
4778 start_step_over (get_thread_lwp (need_step_over
));
4783 threads_debug_printf ("Proceeding, no step-over needed");
4785 for_each_thread ([this] (thread_info
*thread
)
4787 proceed_one_lwp (thread
, NULL
);
4792 linux_process_target::unstop_all_lwps (int unsuspend
, lwp_info
*except
)
4794 THREADS_SCOPED_DEBUG_ENTER_EXIT
;
4797 threads_debug_printf ("except=(LWP %ld)",
4798 lwpid_of (get_lwp_thread (except
)));
4800 threads_debug_printf ("except=nullptr");
4803 for_each_thread ([&] (thread_info
*thread
)
4805 unsuspend_and_proceed_one_lwp (thread
, except
);
4808 for_each_thread ([&] (thread_info
*thread
)
4810 proceed_one_lwp (thread
, except
);
4815 #ifdef HAVE_LINUX_REGSETS
4817 #define use_linux_regsets 1
4819 /* Returns true if REGSET has been disabled. */
4822 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
4824 return (info
->disabled_regsets
!= NULL
4825 && info
->disabled_regsets
[regset
- info
->regsets
]);
4828 /* Disable REGSET. */
4831 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
4835 dr_offset
= regset
- info
->regsets
;
4836 if (info
->disabled_regsets
== NULL
)
4837 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
4838 info
->disabled_regsets
[dr_offset
] = 1;
4842 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
4843 struct regcache
*regcache
)
4845 struct regset_info
*regset
;
4846 int saw_general_regs
= 0;
4850 pid
= lwpid_of (current_thread
);
4851 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4856 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4859 buf
= xmalloc (regset
->size
);
4861 nt_type
= regset
->nt_type
;
4865 iov
.iov_len
= regset
->size
;
4866 data
= (void *) &iov
;
4872 res
= ptrace (regset
->get_request
, pid
,
4873 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4875 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4880 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
4882 /* If we get EIO on a regset, or an EINVAL and the regset is
4883 optional, do not try it again for this process mode. */
4884 disable_regset (regsets_info
, regset
);
4886 else if (errno
== ENODATA
)
4888 /* ENODATA may be returned if the regset is currently
4889 not "active". This can happen in normal operation,
4890 so suppress the warning in this case. */
4892 else if (errno
== ESRCH
)
4894 /* At this point, ESRCH should mean the process is
4895 already gone, in which case we simply ignore attempts
4896 to read its registers. */
4901 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4908 if (regset
->type
== GENERAL_REGS
)
4909 saw_general_regs
= 1;
4910 regset
->store_function (regcache
, buf
);
4914 if (saw_general_regs
)
4921 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
4922 struct regcache
*regcache
)
4924 struct regset_info
*regset
;
4925 int saw_general_regs
= 0;
4929 pid
= lwpid_of (current_thread
);
4930 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4935 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
4936 || regset
->fill_function
== NULL
)
4939 buf
= xmalloc (regset
->size
);
4941 /* First fill the buffer with the current register set contents,
4942 in case there are any items in the kernel's regset that are
4943 not in gdbserver's regcache. */
4945 nt_type
= regset
->nt_type
;
4949 iov
.iov_len
= regset
->size
;
4950 data
= (void *) &iov
;
4956 res
= ptrace (regset
->get_request
, pid
,
4957 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4959 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4964 /* Then overlay our cached registers on that. */
4965 regset
->fill_function (regcache
, buf
);
4967 /* Only now do we write the register set. */
4969 res
= ptrace (regset
->set_request
, pid
,
4970 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4972 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4979 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
4981 /* If we get EIO on a regset, or an EINVAL and the regset is
4982 optional, do not try it again for this process mode. */
4983 disable_regset (regsets_info
, regset
);
4985 else if (errno
== ESRCH
)
4987 /* At this point, ESRCH should mean the process is
4988 already gone, in which case we simply ignore attempts
4989 to change its registers. See also the related
4990 comment in resume_one_lwp. */
4996 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4999 else if (regset
->type
== GENERAL_REGS
)
5000 saw_general_regs
= 1;
5003 if (saw_general_regs
)
5009 #else /* !HAVE_LINUX_REGSETS */
5011 #define use_linux_regsets 0
5012 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5013 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5017 /* Return 1 if register REGNO is supported by one of the regset ptrace
5018 calls or 0 if it has to be transferred individually. */
5021 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5023 unsigned char mask
= 1 << (regno
% 8);
5024 size_t index
= regno
/ 8;
5026 return (use_linux_regsets
5027 && (regs_info
->regset_bitmap
== NULL
5028 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5031 #ifdef HAVE_LINUX_USRREGS
5034 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5038 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5039 error ("Invalid register number %d.", regnum
);
5041 addr
= usrregs
->regmap
[regnum
];
5048 linux_process_target::fetch_register (const usrregs_info
*usrregs
,
5049 regcache
*regcache
, int regno
)
5056 if (regno
>= usrregs
->num_regs
)
5058 if (low_cannot_fetch_register (regno
))
5061 regaddr
= register_addr (usrregs
, regno
);
5065 size
= ((register_size (regcache
->tdesc
, regno
)
5066 + sizeof (PTRACE_XFER_TYPE
) - 1)
5067 & -sizeof (PTRACE_XFER_TYPE
));
5068 buf
= (char *) alloca (size
);
5070 pid
= lwpid_of (current_thread
);
5071 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5074 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5075 ptrace (PTRACE_PEEKUSER
, pid
,
5076 /* Coerce to a uintptr_t first to avoid potential gcc warning
5077 of coercing an 8 byte integer to a 4 byte pointer. */
5078 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5079 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5082 /* Mark register REGNO unavailable. */
5083 supply_register (regcache
, regno
, NULL
);
5088 low_supply_ptrace_register (regcache
, regno
, buf
);
5092 linux_process_target::store_register (const usrregs_info
*usrregs
,
5093 regcache
*regcache
, int regno
)
5100 if (regno
>= usrregs
->num_regs
)
5102 if (low_cannot_store_register (regno
))
5105 regaddr
= register_addr (usrregs
, regno
);
5109 size
= ((register_size (regcache
->tdesc
, regno
)
5110 + sizeof (PTRACE_XFER_TYPE
) - 1)
5111 & -sizeof (PTRACE_XFER_TYPE
));
5112 buf
= (char *) alloca (size
);
5113 memset (buf
, 0, size
);
5115 low_collect_ptrace_register (regcache
, regno
, buf
);
5117 pid
= lwpid_of (current_thread
);
5118 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5121 ptrace (PTRACE_POKEUSER
, pid
,
5122 /* Coerce to a uintptr_t first to avoid potential gcc warning
5123 about coercing an 8 byte integer to a 4 byte pointer. */
5124 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5125 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5128 /* At this point, ESRCH should mean the process is
5129 already gone, in which case we simply ignore attempts
5130 to change its registers. See also the related
5131 comment in resume_one_lwp. */
5136 if (!low_cannot_store_register (regno
))
5137 error ("writing register %d: %s", regno
, safe_strerror (errno
));
5139 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5142 #endif /* HAVE_LINUX_USRREGS */
5145 linux_process_target::low_collect_ptrace_register (regcache
*regcache
,
5146 int regno
, char *buf
)
5148 collect_register (regcache
, regno
, buf
);
5152 linux_process_target::low_supply_ptrace_register (regcache
*regcache
,
5153 int regno
, const char *buf
)
5155 supply_register (regcache
, regno
, buf
);
5159 linux_process_target::usr_fetch_inferior_registers (const regs_info
*regs_info
,
5163 #ifdef HAVE_LINUX_USRREGS
5164 struct usrregs_info
*usr
= regs_info
->usrregs
;
5168 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5169 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5170 fetch_register (usr
, regcache
, regno
);
5173 fetch_register (usr
, regcache
, regno
);
5178 linux_process_target::usr_store_inferior_registers (const regs_info
*regs_info
,
5182 #ifdef HAVE_LINUX_USRREGS
5183 struct usrregs_info
*usr
= regs_info
->usrregs
;
5187 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5188 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5189 store_register (usr
, regcache
, regno
);
5192 store_register (usr
, regcache
, regno
);
5197 linux_process_target::fetch_registers (regcache
*regcache
, int regno
)
5201 const regs_info
*regs_info
= get_regs_info ();
5205 if (regs_info
->usrregs
!= NULL
)
5206 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5207 low_fetch_register (regcache
, regno
);
5209 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5210 if (regs_info
->usrregs
!= NULL
)
5211 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5215 if (low_fetch_register (regcache
, regno
))
5218 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5220 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5222 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5223 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5228 linux_process_target::store_registers (regcache
*regcache
, int regno
)
5232 const regs_info
*regs_info
= get_regs_info ();
5236 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5238 if (regs_info
->usrregs
!= NULL
)
5239 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5243 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5245 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5247 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5248 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5253 linux_process_target::low_fetch_register (regcache
*regcache
, int regno
)
5258 /* A wrapper for the read_memory target op. */
5261 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5263 return the_target
->read_memory (memaddr
, myaddr
, len
);
5266 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5267 to debugger memory starting at MYADDR. */
5270 linux_process_target::read_memory (CORE_ADDR memaddr
,
5271 unsigned char *myaddr
, int len
)
5273 int pid
= lwpid_of (current_thread
);
5274 PTRACE_XFER_TYPE
*buffer
;
5282 /* Try using /proc. Don't bother for one word. */
5283 if (len
>= 3 * sizeof (long))
5287 /* We could keep this file open and cache it - possibly one per
5288 thread. That requires some juggling, but is even faster. */
5289 sprintf (filename
, "/proc/%d/mem", pid
);
5290 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5294 /* If pread64 is available, use it. It's faster if the kernel
5295 supports it (only one syscall), and it's 64-bit safe even on
5296 32-bit platforms (for instance, SPARC debugging a SPARC64
5299 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5302 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5303 bytes
= read (fd
, myaddr
, len
);
5310 /* Some data was read, we'll try to get the rest with ptrace. */
5320 /* Round starting address down to longword boundary. */
5321 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5322 /* Round ending address up; get number of longwords that makes. */
5323 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5324 / sizeof (PTRACE_XFER_TYPE
));
5325 /* Allocate buffer of that many longwords. */
5326 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5328 /* Read all the longwords */
5330 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5332 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5333 about coercing an 8 byte integer to a 4 byte pointer. */
5334 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5335 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5336 (PTRACE_TYPE_ARG4
) 0);
5342 /* Copy appropriate bytes out of the buffer. */
5345 i
*= sizeof (PTRACE_XFER_TYPE
);
5346 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5348 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5355 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5356 memory at MEMADDR. On failure (cannot write to the inferior)
5357 returns the value of errno. Always succeeds if LEN is zero. */
5360 linux_process_target::write_memory (CORE_ADDR memaddr
,
5361 const unsigned char *myaddr
, int len
)
5364 /* Round starting address down to longword boundary. */
5365 CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5366 /* Round ending address up; get number of longwords that makes. */
5368 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5369 / sizeof (PTRACE_XFER_TYPE
);
5371 /* Allocate buffer of that many longwords. */
5372 PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5374 int pid
= lwpid_of (current_thread
);
5378 /* Zero length write always succeeds. */
5384 /* Dump up to four bytes. */
5385 char str
[4 * 2 + 1];
5387 int dump
= len
< 4 ? len
: 4;
5389 for (i
= 0; i
< dump
; i
++)
5391 sprintf (p
, "%02x", myaddr
[i
]);
5396 threads_debug_printf ("Writing %s to 0x%08lx in process %d",
5397 str
, (long) memaddr
, pid
);
5400 /* Fill start and end extra bytes of buffer with existing memory data. */
5403 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5404 about coercing an 8 byte integer to a 4 byte pointer. */
5405 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5406 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5407 (PTRACE_TYPE_ARG4
) 0);
5415 = ptrace (PTRACE_PEEKTEXT
, pid
,
5416 /* Coerce to a uintptr_t first to avoid potential gcc warning
5417 about coercing an 8 byte integer to a 4 byte pointer. */
5418 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5419 * sizeof (PTRACE_XFER_TYPE
)),
5420 (PTRACE_TYPE_ARG4
) 0);
5425 /* Copy data to be written over corresponding part of buffer. */
5427 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5430 /* Write the entire buffer. */
5432 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5435 ptrace (PTRACE_POKETEXT
, pid
,
5436 /* Coerce to a uintptr_t first to avoid potential gcc warning
5437 about coercing an 8 byte integer to a 4 byte pointer. */
5438 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5439 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5448 linux_process_target::look_up_symbols ()
5450 #ifdef USE_THREAD_DB
5451 struct process_info
*proc
= current_process ();
5453 if (proc
->priv
->thread_db
!= NULL
)
5461 linux_process_target::request_interrupt ()
5463 /* Send a SIGINT to the process group. This acts just like the user
5464 typed a ^C on the controlling terminal. */
5465 ::kill (-signal_pid
, SIGINT
);
5469 linux_process_target::supports_read_auxv ()
5474 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5475 to debugger memory starting at MYADDR. */
5478 linux_process_target::read_auxv (CORE_ADDR offset
, unsigned char *myaddr
,
5481 char filename
[PATH_MAX
];
5483 int pid
= lwpid_of (current_thread
);
5485 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5487 fd
= open (filename
, O_RDONLY
);
5491 if (offset
!= (CORE_ADDR
) 0
5492 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5495 n
= read (fd
, myaddr
, len
);
5503 linux_process_target::insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5504 int size
, raw_breakpoint
*bp
)
5506 if (type
== raw_bkpt_type_sw
)
5507 return insert_memory_breakpoint (bp
);
5509 return low_insert_point (type
, addr
, size
, bp
);
5513 linux_process_target::low_insert_point (raw_bkpt_type type
, CORE_ADDR addr
,
5514 int size
, raw_breakpoint
*bp
)
5516 /* Unsupported (see target.h). */
5521 linux_process_target::remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5522 int size
, raw_breakpoint
*bp
)
5524 if (type
== raw_bkpt_type_sw
)
5525 return remove_memory_breakpoint (bp
);
5527 return low_remove_point (type
, addr
, size
, bp
);
5531 linux_process_target::low_remove_point (raw_bkpt_type type
, CORE_ADDR addr
,
5532 int size
, raw_breakpoint
*bp
)
5534 /* Unsupported (see target.h). */
5538 /* Implement the stopped_by_sw_breakpoint target_ops
5542 linux_process_target::stopped_by_sw_breakpoint ()
5544 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5546 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5549 /* Implement the supports_stopped_by_sw_breakpoint target_ops
5553 linux_process_target::supports_stopped_by_sw_breakpoint ()
5555 return USE_SIGTRAP_SIGINFO
;
5558 /* Implement the stopped_by_hw_breakpoint target_ops
5562 linux_process_target::stopped_by_hw_breakpoint ()
5564 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5566 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5569 /* Implement the supports_stopped_by_hw_breakpoint target_ops
5573 linux_process_target::supports_stopped_by_hw_breakpoint ()
5575 return USE_SIGTRAP_SIGINFO
;
5578 /* Implement the supports_hardware_single_step target_ops method. */
5581 linux_process_target::supports_hardware_single_step ()
5587 linux_process_target::stopped_by_watchpoint ()
5589 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5591 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5595 linux_process_target::stopped_data_address ()
5597 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5599 return lwp
->stopped_data_address
;
5602 /* This is only used for targets that define PT_TEXT_ADDR,
5603 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5604 the target has different ways of acquiring this information, like
5608 linux_process_target::supports_read_offsets ()
5610 #ifdef SUPPORTS_READ_OFFSETS
5617 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5618 to tell gdb about. */
5621 linux_process_target::read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5623 #ifdef SUPPORTS_READ_OFFSETS
5624 unsigned long text
, text_end
, data
;
5625 int pid
= lwpid_of (current_thread
);
5629 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5630 (PTRACE_TYPE_ARG4
) 0);
5631 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5632 (PTRACE_TYPE_ARG4
) 0);
5633 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5634 (PTRACE_TYPE_ARG4
) 0);
5638 /* Both text and data offsets produced at compile-time (and so
5639 used by gdb) are relative to the beginning of the program,
5640 with the data segment immediately following the text segment.
5641 However, the actual runtime layout in memory may put the data
5642 somewhere else, so when we send gdb a data base-address, we
5643 use the real data base address and subtract the compile-time
5644 data base-address from it (which is just the length of the
5645 text segment). BSS immediately follows data in both
5648 *data_p
= data
- (text_end
- text
);
5654 gdb_assert_not_reached ("target op read_offsets not supported");
5659 linux_process_target::supports_get_tls_address ()
5661 #ifdef USE_THREAD_DB
5669 linux_process_target::get_tls_address (thread_info
*thread
,
5671 CORE_ADDR load_module
,
5674 #ifdef USE_THREAD_DB
5675 return thread_db_get_tls_address (thread
, offset
, load_module
, address
);
5682 linux_process_target::supports_qxfer_osdata ()
5688 linux_process_target::qxfer_osdata (const char *annex
,
5689 unsigned char *readbuf
,
5690 unsigned const char *writebuf
,
5691 CORE_ADDR offset
, int len
)
5693 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5697 linux_process_target::siginfo_fixup (siginfo_t
*siginfo
,
5698 gdb_byte
*inf_siginfo
, int direction
)
5700 bool done
= low_siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5702 /* If there was no callback, or the callback didn't do anything,
5703 then just do a straight memcpy. */
5707 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5709 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5714 linux_process_target::low_siginfo_fixup (siginfo_t
*native
, gdb_byte
*inf
,
5721 linux_process_target::supports_qxfer_siginfo ()
5727 linux_process_target::qxfer_siginfo (const char *annex
,
5728 unsigned char *readbuf
,
5729 unsigned const char *writebuf
,
5730 CORE_ADDR offset
, int len
)
5734 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
5736 if (current_thread
== NULL
)
5739 pid
= lwpid_of (current_thread
);
5741 threads_debug_printf ("%s siginfo for lwp %d.",
5742 readbuf
!= NULL
? "Reading" : "Writing",
5745 if (offset
>= sizeof (siginfo
))
5748 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5751 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5752 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5753 inferior with a 64-bit GDBSERVER should look the same as debugging it
5754 with a 32-bit GDBSERVER, we need to convert it. */
5755 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
5757 if (offset
+ len
> sizeof (siginfo
))
5758 len
= sizeof (siginfo
) - offset
;
5760 if (readbuf
!= NULL
)
5761 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
5764 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
5766 /* Convert back to ptrace layout before flushing it out. */
5767 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
5769 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5776 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5777 so we notice when children change state; as the handler for the
5778 sigsuspend in my_waitpid. */
5781 sigchld_handler (int signo
)
5783 int old_errno
= errno
;
5789 /* Use the async signal safe debug function. */
5790 if (debug_write ("sigchld_handler\n",
5791 sizeof ("sigchld_handler\n") - 1) < 0)
5792 break; /* just ignore */
5796 if (target_is_async_p ())
5797 async_file_mark (); /* trigger a linux_wait */
5803 linux_process_target::supports_non_stop ()
5809 linux_process_target::async (bool enable
)
5811 bool previous
= target_is_async_p ();
5813 threads_debug_printf ("async (%d), previous=%d",
5816 if (previous
!= enable
)
5819 sigemptyset (&mask
);
5820 sigaddset (&mask
, SIGCHLD
);
5822 gdb_sigmask (SIG_BLOCK
, &mask
, NULL
);
5826 if (pipe (linux_event_pipe
) == -1)
5828 linux_event_pipe
[0] = -1;
5829 linux_event_pipe
[1] = -1;
5830 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
5832 warning ("creating event pipe failed.");
5836 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5837 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5839 /* Register the event loop handler. */
5840 add_file_handler (linux_event_pipe
[0],
5841 handle_target_event
, NULL
,
5844 /* Always trigger a linux_wait. */
5849 delete_file_handler (linux_event_pipe
[0]);
5851 close (linux_event_pipe
[0]);
5852 close (linux_event_pipe
[1]);
5853 linux_event_pipe
[0] = -1;
5854 linux_event_pipe
[1] = -1;
5857 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
5864 linux_process_target::start_non_stop (bool nonstop
)
5866 /* Register or unregister from event-loop accordingly. */
5867 target_async (nonstop
);
5869 if (target_is_async_p () != (nonstop
!= false))
5876 linux_process_target::supports_multi_process ()
5881 /* Check if fork events are supported. */
5884 linux_process_target::supports_fork_events ()
5889 /* Check if vfork events are supported. */
5892 linux_process_target::supports_vfork_events ()
5897 /* Check if exec events are supported. */
5900 linux_process_target::supports_exec_events ()
5905 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
5906 ptrace flags for all inferiors. This is in case the new GDB connection
5907 doesn't support the same set of events that the previous one did. */
5910 linux_process_target::handle_new_gdb_connection ()
5912 /* Request that all the lwps reset their ptrace options. */
5913 for_each_thread ([] (thread_info
*thread
)
5915 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5919 /* Stop the lwp so we can modify its ptrace options. */
5920 lwp
->must_set_ptrace_flags
= 1;
5921 linux_stop_lwp (lwp
);
5925 /* Already stopped; go ahead and set the ptrace options. */
5926 struct process_info
*proc
= find_process_pid (pid_of (thread
));
5927 int options
= linux_low_ptrace_options (proc
->attached
);
5929 linux_enable_event_reporting (lwpid_of (thread
), options
);
5930 lwp
->must_set_ptrace_flags
= 0;
5936 linux_process_target::handle_monitor_command (char *mon
)
5938 #ifdef USE_THREAD_DB
5939 return thread_db_handle_monitor_command (mon
);
5946 linux_process_target::core_of_thread (ptid_t ptid
)
5948 return linux_common_core_of_thread (ptid
);
5952 linux_process_target::supports_disable_randomization ()
5958 linux_process_target::supports_agent ()
5964 linux_process_target::supports_range_stepping ()
5966 if (supports_software_single_step ())
5969 return low_supports_range_stepping ();
5973 linux_process_target::low_supports_range_stepping ()
5979 linux_process_target::supports_pid_to_exec_file ()
5985 linux_process_target::pid_to_exec_file (int pid
)
5987 return linux_proc_pid_to_exec_file (pid
);
5991 linux_process_target::supports_multifs ()
5997 linux_process_target::multifs_open (int pid
, const char *filename
,
5998 int flags
, mode_t mode
)
6000 return linux_mntns_open_cloexec (pid
, filename
, flags
, mode
);
6004 linux_process_target::multifs_unlink (int pid
, const char *filename
)
6006 return linux_mntns_unlink (pid
, filename
);
6010 linux_process_target::multifs_readlink (int pid
, const char *filename
,
6011 char *buf
, size_t bufsiz
)
6013 return linux_mntns_readlink (pid
, filename
, buf
, bufsiz
);
6016 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6017 struct target_loadseg
6019 /* Core address to which the segment is mapped. */
6021 /* VMA recorded in the program header. */
6023 /* Size of this segment in memory. */
6027 # if defined PT_GETDSBT
6028 struct target_loadmap
6030 /* Protocol version number, must be zero. */
6032 /* Pointer to the DSBT table, its size, and the DSBT index. */
6033 unsigned *dsbt_table
;
6034 unsigned dsbt_size
, dsbt_index
;
6035 /* Number of segments in this map. */
6037 /* The actual memory map. */
6038 struct target_loadseg segs
[/*nsegs*/];
6040 # define LINUX_LOADMAP PT_GETDSBT
6041 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6042 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6044 struct target_loadmap
6046 /* Protocol version number, must be zero. */
6048 /* Number of segments in this map. */
6050 /* The actual memory map. */
6051 struct target_loadseg segs
[/*nsegs*/];
6053 # define LINUX_LOADMAP PTRACE_GETFDPIC
6054 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6055 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6059 linux_process_target::supports_read_loadmap ()
6065 linux_process_target::read_loadmap (const char *annex
, CORE_ADDR offset
,
6066 unsigned char *myaddr
, unsigned int len
)
6068 int pid
= lwpid_of (current_thread
);
6070 struct target_loadmap
*data
= NULL
;
6071 unsigned int actual_length
, copy_length
;
6073 if (strcmp (annex
, "exec") == 0)
6074 addr
= (int) LINUX_LOADMAP_EXEC
;
6075 else if (strcmp (annex
, "interp") == 0)
6076 addr
= (int) LINUX_LOADMAP_INTERP
;
6080 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6086 actual_length
= sizeof (struct target_loadmap
)
6087 + sizeof (struct target_loadseg
) * data
->nsegs
;
6089 if (offset
< 0 || offset
> actual_length
)
6092 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6093 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6096 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6099 linux_process_target::supports_catch_syscall ()
6101 return low_supports_catch_syscall ();
6105 linux_process_target::low_supports_catch_syscall ()
6111 linux_process_target::read_pc (regcache
*regcache
)
6113 if (!low_supports_breakpoints ())
6116 return low_get_pc (regcache
);
6120 linux_process_target::write_pc (regcache
*regcache
, CORE_ADDR pc
)
6122 gdb_assert (low_supports_breakpoints ());
6124 low_set_pc (regcache
, pc
);
6128 linux_process_target::supports_thread_stopped ()
6134 linux_process_target::thread_stopped (thread_info
*thread
)
6136 return get_thread_lwp (thread
)->stopped
;
6139 /* This exposes stop-all-threads functionality to other modules. */
6142 linux_process_target::pause_all (bool freeze
)
6144 stop_all_lwps (freeze
, NULL
);
6147 /* This exposes unstop-all-threads functionality to other gdbserver
6151 linux_process_target::unpause_all (bool unfreeze
)
6153 unstop_all_lwps (unfreeze
, NULL
);
6157 linux_process_target::prepare_to_access_memory ()
6159 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6162 target_pause_all (true);
6167 linux_process_target::done_accessing_memory ()
6169 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6172 target_unpause_all (true);
6175 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6178 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6179 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6181 char filename
[PATH_MAX
];
6183 const int auxv_size
= is_elf64
6184 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6185 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6187 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6189 fd
= open (filename
, O_RDONLY
);
6195 while (read (fd
, buf
, auxv_size
) == auxv_size
6196 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6200 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6202 switch (aux
->a_type
)
6205 *phdr_memaddr
= aux
->a_un
.a_val
;
6208 *num_phdr
= aux
->a_un
.a_val
;
6214 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6216 switch (aux
->a_type
)
6219 *phdr_memaddr
= aux
->a_un
.a_val
;
6222 *num_phdr
= aux
->a_un
.a_val
;
6230 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6232 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6233 "phdr_memaddr = %ld, phdr_num = %d",
6234 (long) *phdr_memaddr
, *num_phdr
);
6241 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6244 get_dynamic (const int pid
, const int is_elf64
)
6246 CORE_ADDR phdr_memaddr
, relocation
;
6248 unsigned char *phdr_buf
;
6249 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6251 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6254 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6255 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6257 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6260 /* Compute relocation: it is expected to be 0 for "regular" executables,
6261 non-zero for PIE ones. */
6263 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6266 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6268 if (p
->p_type
== PT_PHDR
)
6269 relocation
= phdr_memaddr
- p
->p_vaddr
;
6273 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6275 if (p
->p_type
== PT_PHDR
)
6276 relocation
= phdr_memaddr
- p
->p_vaddr
;
6279 if (relocation
== -1)
6281 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6282 any real world executables, including PIE executables, have always
6283 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6284 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6285 or present DT_DEBUG anyway (fpc binaries are statically linked).
6287 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6289 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6294 for (i
= 0; i
< num_phdr
; i
++)
6298 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6300 if (p
->p_type
== PT_DYNAMIC
)
6301 return p
->p_vaddr
+ relocation
;
6305 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6307 if (p
->p_type
== PT_DYNAMIC
)
6308 return p
->p_vaddr
+ relocation
;
6315 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6316 can be 0 if the inferior does not yet have the library list initialized.
6317 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6318 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6321 get_r_debug (const int pid
, const int is_elf64
)
6323 CORE_ADDR dynamic_memaddr
;
6324 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6325 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6328 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6329 if (dynamic_memaddr
== 0)
6332 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6336 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6337 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6341 unsigned char buf
[sizeof (Elf64_Xword
)];
6345 #ifdef DT_MIPS_RLD_MAP
6346 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6348 if (linux_read_memory (dyn
->d_un
.d_val
,
6349 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6354 #endif /* DT_MIPS_RLD_MAP */
6355 #ifdef DT_MIPS_RLD_MAP_REL
6356 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6358 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6359 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6364 #endif /* DT_MIPS_RLD_MAP_REL */
6366 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6367 map
= dyn
->d_un
.d_val
;
6369 if (dyn
->d_tag
== DT_NULL
)
6374 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6375 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6379 unsigned char buf
[sizeof (Elf32_Word
)];
6383 #ifdef DT_MIPS_RLD_MAP
6384 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6386 if (linux_read_memory (dyn
->d_un
.d_val
,
6387 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6392 #endif /* DT_MIPS_RLD_MAP */
6393 #ifdef DT_MIPS_RLD_MAP_REL
6394 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6396 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6397 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6402 #endif /* DT_MIPS_RLD_MAP_REL */
6404 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6405 map
= dyn
->d_un
.d_val
;
6407 if (dyn
->d_tag
== DT_NULL
)
6411 dynamic_memaddr
+= dyn_size
;
6417 /* Read one pointer from MEMADDR in the inferior. */
6420 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6424 /* Go through a union so this works on either big or little endian
6425 hosts, when the inferior's pointer size is smaller than the size
6426 of CORE_ADDR. It is assumed the inferior's endianness is the
6427 same of the superior's. */
6430 CORE_ADDR core_addr
;
6435 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6438 if (ptr_size
== sizeof (CORE_ADDR
))
6439 *ptr
= addr
.core_addr
;
6440 else if (ptr_size
== sizeof (unsigned int))
6443 gdb_assert_not_reached ("unhandled pointer size");
6449 linux_process_target::supports_qxfer_libraries_svr4 ()
6454 struct link_map_offsets
6456 /* Offset and size of r_debug.r_version. */
6457 int r_version_offset
;
6459 /* Offset and size of r_debug.r_map. */
6462 /* Offset to l_addr field in struct link_map. */
6465 /* Offset to l_name field in struct link_map. */
6468 /* Offset to l_ld field in struct link_map. */
6471 /* Offset to l_next field in struct link_map. */
6474 /* Offset to l_prev field in struct link_map. */
6478 /* Construct qXfer:libraries-svr4:read reply. */
6481 linux_process_target::qxfer_libraries_svr4 (const char *annex
,
6482 unsigned char *readbuf
,
6483 unsigned const char *writebuf
,
6484 CORE_ADDR offset
, int len
)
6486 struct process_info_private
*const priv
= current_process ()->priv
;
6487 char filename
[PATH_MAX
];
6490 static const struct link_map_offsets lmo_32bit_offsets
=
6492 0, /* r_version offset. */
6493 4, /* r_debug.r_map offset. */
6494 0, /* l_addr offset in link_map. */
6495 4, /* l_name offset in link_map. */
6496 8, /* l_ld offset in link_map. */
6497 12, /* l_next offset in link_map. */
6498 16 /* l_prev offset in link_map. */
6501 static const struct link_map_offsets lmo_64bit_offsets
=
6503 0, /* r_version offset. */
6504 8, /* r_debug.r_map offset. */
6505 0, /* l_addr offset in link_map. */
6506 8, /* l_name offset in link_map. */
6507 16, /* l_ld offset in link_map. */
6508 24, /* l_next offset in link_map. */
6509 32 /* l_prev offset in link_map. */
6511 const struct link_map_offsets
*lmo
;
6512 unsigned int machine
;
6514 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6515 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6516 int header_done
= 0;
6518 if (writebuf
!= NULL
)
6520 if (readbuf
== NULL
)
6523 pid
= lwpid_of (current_thread
);
6524 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6525 is_elf64
= elf_64_file_p (filename
, &machine
);
6526 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6527 ptr_size
= is_elf64
? 8 : 4;
6529 while (annex
[0] != '\0')
6535 sep
= strchr (annex
, '=');
6539 name_len
= sep
- annex
;
6540 if (name_len
== 5 && startswith (annex
, "start"))
6542 else if (name_len
== 4 && startswith (annex
, "prev"))
6546 annex
= strchr (sep
, ';');
6553 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6560 if (priv
->r_debug
== 0)
6561 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6563 /* We failed to find DT_DEBUG. Such situation will not change
6564 for this inferior - do not retry it. Report it to GDB as
6565 E01, see for the reasons at the GDB solib-svr4.c side. */
6566 if (priv
->r_debug
== (CORE_ADDR
) -1)
6569 if (priv
->r_debug
!= 0)
6571 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6572 (unsigned char *) &r_version
,
6573 sizeof (r_version
)) != 0
6576 warning ("unexpected r_debug version %d", r_version
);
6578 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6579 &lm_addr
, ptr_size
) != 0)
6581 warning ("unable to read r_map from 0x%lx",
6582 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6587 std::string document
= "<library-list-svr4 version=\"1.0\"";
6590 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6591 &l_name
, ptr_size
) == 0
6592 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6593 &l_addr
, ptr_size
) == 0
6594 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6595 &l_ld
, ptr_size
) == 0
6596 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6597 &l_prev
, ptr_size
) == 0
6598 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6599 &l_next
, ptr_size
) == 0)
6601 unsigned char libname
[PATH_MAX
];
6603 if (lm_prev
!= l_prev
)
6605 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6606 (long) lm_prev
, (long) l_prev
);
6610 /* Ignore the first entry even if it has valid name as the first entry
6611 corresponds to the main executable. The first entry should not be
6612 skipped if the dynamic loader was loaded late by a static executable
6613 (see solib-svr4.c parameter ignore_first). But in such case the main
6614 executable does not have PT_DYNAMIC present and this function already
6615 exited above due to failed get_r_debug. */
6617 string_appendf (document
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6620 /* Not checking for error because reading may stop before
6621 we've got PATH_MAX worth of characters. */
6623 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6624 libname
[sizeof (libname
) - 1] = '\0';
6625 if (libname
[0] != '\0')
6629 /* Terminate `<library-list-svr4'. */
6634 string_appendf (document
, "<library name=\"");
6635 xml_escape_text_append (&document
, (char *) libname
);
6636 string_appendf (document
, "\" lm=\"0x%lx\" "
6637 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6638 (unsigned long) lm_addr
, (unsigned long) l_addr
,
6639 (unsigned long) l_ld
);
6649 /* Empty list; terminate `<library-list-svr4'. */
6653 document
+= "</library-list-svr4>";
6655 int document_len
= document
.length ();
6656 if (offset
< document_len
)
6657 document_len
-= offset
;
6660 if (len
> document_len
)
6663 memcpy (readbuf
, document
.data () + offset
, len
);
6668 #ifdef HAVE_LINUX_BTRACE
6670 btrace_target_info
*
6671 linux_process_target::enable_btrace (thread_info
*tp
,
6672 const btrace_config
*conf
)
6674 return linux_enable_btrace (tp
->id
, conf
);
6677 /* See to_disable_btrace target method. */
6680 linux_process_target::disable_btrace (btrace_target_info
*tinfo
)
6682 enum btrace_error err
;
6684 err
= linux_disable_btrace (tinfo
);
6685 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6688 /* Encode an Intel Processor Trace configuration. */
6691 linux_low_encode_pt_config (struct buffer
*buffer
,
6692 const struct btrace_data_pt_config
*config
)
6694 buffer_grow_str (buffer
, "<pt-config>\n");
6696 switch (config
->cpu
.vendor
)
6699 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
6700 "model=\"%u\" stepping=\"%u\"/>\n",
6701 config
->cpu
.family
, config
->cpu
.model
,
6702 config
->cpu
.stepping
);
6709 buffer_grow_str (buffer
, "</pt-config>\n");
6712 /* Encode a raw buffer. */
6715 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
6721 /* We use hex encoding - see gdbsupport/rsp-low.h. */
6722 buffer_grow_str (buffer
, "<raw>\n");
6728 elem
[0] = tohex ((*data
>> 4) & 0xf);
6729 elem
[1] = tohex (*data
++ & 0xf);
6731 buffer_grow (buffer
, elem
, 2);
6734 buffer_grow_str (buffer
, "</raw>\n");
6737 /* See to_read_btrace target method. */
6740 linux_process_target::read_btrace (btrace_target_info
*tinfo
,
6742 enum btrace_read_type type
)
6744 struct btrace_data btrace
;
6745 enum btrace_error err
;
6747 err
= linux_read_btrace (&btrace
, tinfo
, type
);
6748 if (err
!= BTRACE_ERR_NONE
)
6750 if (err
== BTRACE_ERR_OVERFLOW
)
6751 buffer_grow_str0 (buffer
, "E.Overflow.");
6753 buffer_grow_str0 (buffer
, "E.Generic Error.");
6758 switch (btrace
.format
)
6760 case BTRACE_FORMAT_NONE
:
6761 buffer_grow_str0 (buffer
, "E.No Trace.");
6764 case BTRACE_FORMAT_BTS
:
6765 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6766 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6768 for (const btrace_block
&block
: *btrace
.variant
.bts
.blocks
)
6769 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
6770 paddress (block
.begin
), paddress (block
.end
));
6772 buffer_grow_str0 (buffer
, "</btrace>\n");
6775 case BTRACE_FORMAT_PT
:
6776 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6777 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6778 buffer_grow_str (buffer
, "<pt>\n");
6780 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
6782 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
6783 btrace
.variant
.pt
.size
);
6785 buffer_grow_str (buffer
, "</pt>\n");
6786 buffer_grow_str0 (buffer
, "</btrace>\n");
6790 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
6797 /* See to_btrace_conf target method. */
6800 linux_process_target::read_btrace_conf (const btrace_target_info
*tinfo
,
6803 const struct btrace_config
*conf
;
6805 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
6806 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
6808 conf
= linux_btrace_conf (tinfo
);
6811 switch (conf
->format
)
6813 case BTRACE_FORMAT_NONE
:
6816 case BTRACE_FORMAT_BTS
:
6817 buffer_xml_printf (buffer
, "<bts");
6818 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
6819 buffer_xml_printf (buffer
, " />\n");
6822 case BTRACE_FORMAT_PT
:
6823 buffer_xml_printf (buffer
, "<pt");
6824 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
6825 buffer_xml_printf (buffer
, "/>\n");
6830 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
6833 #endif /* HAVE_LINUX_BTRACE */
6835 /* See nat/linux-nat.h. */
6838 current_lwp_ptid (void)
6840 return ptid_of (current_thread
);
6844 linux_process_target::thread_name (ptid_t thread
)
6846 return linux_proc_tid_get_name (thread
);
6851 linux_process_target::thread_handle (ptid_t ptid
, gdb_byte
**handle
,
6854 return thread_db_thread_handle (ptid
, handle
, handle_len
);
6859 linux_process_target::thread_pending_parent (thread_info
*thread
)
6861 lwp_info
*parent
= get_thread_lwp (thread
)->pending_parent ();
6863 if (parent
== nullptr)
6866 return get_lwp_thread (parent
);
6870 linux_process_target::thread_pending_child (thread_info
*thread
)
6872 lwp_info
*child
= get_thread_lwp (thread
)->pending_child ();
6874 if (child
== nullptr)
6877 return get_lwp_thread (child
);
6880 /* Default implementation of linux_target_ops method "set_pc" for
6881 32-bit pc register which is literally named "pc". */
6884 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
6886 uint32_t newpc
= pc
;
6888 supply_register_by_name (regcache
, "pc", &newpc
);
6891 /* Default implementation of linux_target_ops method "get_pc" for
6892 32-bit pc register which is literally named "pc". */
6895 linux_get_pc_32bit (struct regcache
*regcache
)
6899 collect_register_by_name (regcache
, "pc", &pc
);
6900 threads_debug_printf ("stop pc is 0x%" PRIx32
, pc
);
6904 /* Default implementation of linux_target_ops method "set_pc" for
6905 64-bit pc register which is literally named "pc". */
6908 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
6910 uint64_t newpc
= pc
;
6912 supply_register_by_name (regcache
, "pc", &newpc
);
6915 /* Default implementation of linux_target_ops method "get_pc" for
6916 64-bit pc register which is literally named "pc". */
6919 linux_get_pc_64bit (struct regcache
*regcache
)
6923 collect_register_by_name (regcache
, "pc", &pc
);
6924 threads_debug_printf ("stop pc is 0x%" PRIx64
, pc
);
6928 /* See linux-low.h. */
6931 linux_get_auxv (int wordsize
, CORE_ADDR match
, CORE_ADDR
*valp
)
6933 gdb_byte
*data
= (gdb_byte
*) alloca (2 * wordsize
);
6936 gdb_assert (wordsize
== 4 || wordsize
== 8);
6938 while (the_target
->read_auxv (offset
, data
, 2 * wordsize
) == 2 * wordsize
)
6942 uint32_t *data_p
= (uint32_t *) data
;
6943 if (data_p
[0] == match
)
6951 uint64_t *data_p
= (uint64_t *) data
;
6952 if (data_p
[0] == match
)
6959 offset
+= 2 * wordsize
;
6965 /* See linux-low.h. */
6968 linux_get_hwcap (int wordsize
)
6970 CORE_ADDR hwcap
= 0;
6971 linux_get_auxv (wordsize
, AT_HWCAP
, &hwcap
);
6975 /* See linux-low.h. */
6978 linux_get_hwcap2 (int wordsize
)
6980 CORE_ADDR hwcap2
= 0;
6981 linux_get_auxv (wordsize
, AT_HWCAP2
, &hwcap2
);
6985 #ifdef HAVE_LINUX_REGSETS
6987 initialize_regsets_info (struct regsets_info
*info
)
6989 for (info
->num_regsets
= 0;
6990 info
->regsets
[info
->num_regsets
].size
>= 0;
6991 info
->num_regsets
++)
6997 initialize_low (void)
6999 struct sigaction sigchld_action
;
7001 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7002 set_target_ops (the_linux_target
);
7004 linux_ptrace_init_warnings ();
7005 linux_proc_init_warnings ();
7007 sigchld_action
.sa_handler
= sigchld_handler
;
7008 sigemptyset (&sigchld_action
.sa_mask
);
7009 sigchld_action
.sa_flags
= SA_RESTART
;
7010 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7012 initialize_low_arch ();
7014 linux_check_ptrace_features ();