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/event-loop.h"
25 #include "gdbsupport/event-pipe.h"
26 #include "gdbsupport/rsp-low.h"
27 #include "gdbsupport/signals-state-save-restore.h"
28 #include "nat/linux-nat.h"
29 #include "nat/linux-waitpid.h"
30 #include "gdbsupport/gdb_wait.h"
31 #include "nat/gdb_ptrace.h"
32 #include "nat/linux-ptrace.h"
33 #include "nat/linux-procfs.h"
34 #include "nat/linux-personality.h"
36 #include <sys/ioctl.h>
39 #include <sys/syscall.h>
43 #include <sys/types.h>
48 #include "gdbsupport/filestuff.h"
49 #include "tracepoint.h"
51 #include "gdbsupport/common-inferior.h"
52 #include "nat/fork-inferior.h"
53 #include "gdbsupport/environ.h"
54 #include "gdbsupport/gdb-sigmask.h"
55 #include "gdbsupport/scoped_restore.h"
57 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
58 then ELFMAG0 will have been defined. If it didn't get included by
59 gdb_proc_service.h then including it will likely introduce a duplicate
60 definition of elf_fpregset_t. */
63 #include "nat/linux-namespaces.h"
73 /* Some targets did not define these ptrace constants from the start,
74 so gdbserver defines them locally here. In the future, these may
75 be removed after they are added to asm/ptrace.h. */
76 #if !(defined(PT_TEXT_ADDR) \
77 || defined(PT_DATA_ADDR) \
78 || defined(PT_TEXT_END_ADDR))
79 #if defined(__mcoldfire__)
80 /* These are still undefined in 3.10 kernels. */
81 #define PT_TEXT_ADDR 49*4
82 #define PT_DATA_ADDR 50*4
83 #define PT_TEXT_END_ADDR 51*4
84 /* These are still undefined in 3.10 kernels. */
85 #elif defined(__TMS320C6X__)
86 #define PT_TEXT_ADDR (0x10000*4)
87 #define PT_DATA_ADDR (0x10004*4)
88 #define PT_TEXT_END_ADDR (0x10008*4)
92 #if (defined(__UCLIBC__) \
93 && defined(HAS_NOMMU) \
94 && defined(PT_TEXT_ADDR) \
95 && defined(PT_DATA_ADDR) \
96 && defined(PT_TEXT_END_ADDR))
97 #define SUPPORTS_READ_OFFSETS
100 #ifdef HAVE_LINUX_BTRACE
101 # include "nat/linux-btrace.h"
102 # include "gdbsupport/btrace-common.h"
105 #ifndef HAVE_ELF32_AUXV_T
106 /* Copied from glibc's elf.h. */
109 uint32_t a_type
; /* Entry type */
112 uint32_t a_val
; /* Integer value */
113 /* We use to have pointer elements added here. We cannot do that,
114 though, since it does not work when using 32-bit definitions
115 on 64-bit platforms and vice versa. */
120 #ifndef HAVE_ELF64_AUXV_T
121 /* Copied from glibc's elf.h. */
124 uint64_t a_type
; /* Entry type */
127 uint64_t a_val
; /* Integer value */
128 /* We use to have pointer elements added here. We cannot do that,
129 though, since it does not work when using 32-bit definitions
130 on 64-bit platforms and vice versa. */
135 /* Does the current host support PTRACE_GETREGSET? */
136 int have_ptrace_getregset
= -1;
138 /* Return TRUE if THREAD is the leader thread of the process. */
141 is_leader (thread_info
*thread
)
143 ptid_t ptid
= ptid_of (thread
);
144 return ptid
.pid () == ptid
.lwp ();
149 /* See nat/linux-nat.h. */
152 ptid_of_lwp (struct lwp_info
*lwp
)
154 return ptid_of (get_lwp_thread (lwp
));
157 /* See nat/linux-nat.h. */
160 lwp_set_arch_private_info (struct lwp_info
*lwp
,
161 struct arch_lwp_info
*info
)
163 lwp
->arch_private
= info
;
166 /* See nat/linux-nat.h. */
168 struct arch_lwp_info
*
169 lwp_arch_private_info (struct lwp_info
*lwp
)
171 return lwp
->arch_private
;
174 /* See nat/linux-nat.h. */
177 lwp_is_stopped (struct lwp_info
*lwp
)
182 /* See nat/linux-nat.h. */
184 enum target_stop_reason
185 lwp_stop_reason (struct lwp_info
*lwp
)
187 return lwp
->stop_reason
;
190 /* See nat/linux-nat.h. */
193 lwp_is_stepping (struct lwp_info
*lwp
)
195 return lwp
->stepping
;
198 /* A list of all unknown processes which receive stop signals. Some
199 other process will presumably claim each of these as forked
200 children momentarily. */
202 struct simple_pid_list
204 /* The process ID. */
207 /* The status as reported by waitpid. */
211 struct simple_pid_list
*next
;
213 static struct simple_pid_list
*stopped_pids
;
215 /* Trivial list manipulation functions to keep track of a list of new
216 stopped processes. */
219 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
221 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
224 new_pid
->status
= status
;
225 new_pid
->next
= *listp
;
230 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
232 struct simple_pid_list
**p
;
234 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
235 if ((*p
)->pid
== pid
)
237 struct simple_pid_list
*next
= (*p
)->next
;
239 *statusp
= (*p
)->status
;
247 enum stopping_threads_kind
249 /* Not stopping threads presently. */
250 NOT_STOPPING_THREADS
,
252 /* Stopping threads. */
255 /* Stopping and suspending threads. */
256 STOPPING_AND_SUSPENDING_THREADS
259 /* This is set while stop_all_lwps is in effect. */
260 static stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
262 /* FIXME make into a target method? */
263 int using_threads
= 1;
265 /* True if we're presently stabilizing threads (moving them out of
267 static int stabilizing_threads
;
269 static void unsuspend_all_lwps (struct lwp_info
*except
);
270 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
271 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
272 static int kill_lwp (unsigned long lwpid
, int signo
);
273 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
274 static int linux_low_ptrace_options (int attached
);
275 static int check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
);
277 /* When the event-loop is doing a step-over, this points at the thread
279 static ptid_t step_over_bkpt
;
282 linux_process_target::low_supports_breakpoints ()
288 linux_process_target::low_get_pc (regcache
*regcache
)
294 linux_process_target::low_set_pc (regcache
*regcache
, CORE_ADDR newpc
)
296 gdb_assert_not_reached ("linux target op low_set_pc is not implemented");
299 std::vector
<CORE_ADDR
>
300 linux_process_target::low_get_next_pcs (regcache
*regcache
)
302 gdb_assert_not_reached ("linux target op low_get_next_pcs is not "
307 linux_process_target::low_decr_pc_after_break ()
312 /* True if LWP is stopped in its stepping range. */
315 lwp_in_step_range (struct lwp_info
*lwp
)
317 CORE_ADDR pc
= lwp
->stop_pc
;
319 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
322 /* The event pipe registered as a waitable file in the event loop. */
323 static event_pipe linux_event_pipe
;
325 /* True if we're currently in async mode. */
326 #define target_is_async_p() (linux_event_pipe.is_open ())
328 static void send_sigstop (struct lwp_info
*lwp
);
330 /* Return non-zero if HEADER is a 64-bit ELF file. */
333 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
335 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
336 && header
->e_ident
[EI_MAG1
] == ELFMAG1
337 && header
->e_ident
[EI_MAG2
] == ELFMAG2
338 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
340 *machine
= header
->e_machine
;
341 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
348 /* Return non-zero if FILE is a 64-bit ELF file,
349 zero if the file is not a 64-bit ELF file,
350 and -1 if the file is not accessible or doesn't exist. */
353 elf_64_file_p (const char *file
, unsigned int *machine
)
358 fd
= open (file
, O_RDONLY
);
362 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
369 return elf_64_header_p (&header
, machine
);
372 /* Accepts an integer PID; Returns true if the executable PID is
373 running is a 64-bit ELF file.. */
376 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
380 sprintf (file
, "/proc/%d/exe", pid
);
381 return elf_64_file_p (file
, machine
);
385 linux_process_target::delete_lwp (lwp_info
*lwp
)
387 struct thread_info
*thr
= get_lwp_thread (lwp
);
389 threads_debug_printf ("deleting %ld", lwpid_of (thr
));
393 low_delete_thread (lwp
->arch_private
);
399 linux_process_target::low_delete_thread (arch_lwp_info
*info
)
401 /* Default implementation should be overridden if architecture-specific
402 info is being used. */
403 gdb_assert (info
== nullptr);
406 /* Open the /proc/PID/mem file for PROC. */
409 open_proc_mem_file (process_info
*proc
)
411 gdb_assert (proc
->priv
->mem_fd
== -1);
414 xsnprintf (filename
, sizeof filename
, "/proc/%d/mem", proc
->pid
);
417 = gdb_open_cloexec (filename
, O_RDWR
| O_LARGEFILE
, 0).release ();
421 linux_process_target::add_linux_process_no_mem_file (int pid
, int attached
)
423 struct process_info
*proc
;
425 proc
= add_process (pid
, attached
);
426 proc
->priv
= XCNEW (struct process_info_private
);
428 proc
->priv
->arch_private
= low_new_process ();
429 proc
->priv
->mem_fd
= -1;
436 linux_process_target::add_linux_process (int pid
, int attached
)
438 process_info
*proc
= add_linux_process_no_mem_file (pid
, attached
);
439 open_proc_mem_file (proc
);
444 linux_process_target::remove_linux_process (process_info
*proc
)
446 if (proc
->priv
->mem_fd
>= 0)
447 close (proc
->priv
->mem_fd
);
449 this->low_delete_process (proc
->priv
->arch_private
);
452 proc
->priv
= nullptr;
454 remove_process (proc
);
458 linux_process_target::low_new_process ()
464 linux_process_target::low_delete_process (arch_process_info
*info
)
466 /* Default implementation must be overridden if architecture-specific
468 gdb_assert (info
== nullptr);
472 linux_process_target::low_new_fork (process_info
*parent
, process_info
*child
)
478 linux_process_target::arch_setup_thread (thread_info
*thread
)
480 scoped_restore_current_thread restore_thread
;
481 switch_to_thread (thread
);
487 linux_process_target::handle_extended_wait (lwp_info
**orig_event_lwp
,
490 client_state
&cs
= get_client_state ();
491 struct lwp_info
*event_lwp
= *orig_event_lwp
;
492 int event
= linux_ptrace_get_extended_event (wstat
);
493 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
494 struct lwp_info
*new_lwp
;
496 gdb_assert (event_lwp
->waitstatus
.kind () == TARGET_WAITKIND_IGNORE
);
498 /* All extended events we currently use are mid-syscall. Only
499 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
500 you have to be using PTRACE_SEIZE to get that. */
501 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
503 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
504 || (event
== PTRACE_EVENT_CLONE
))
507 unsigned long new_pid
;
510 /* Get the pid of the new lwp. */
511 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
514 /* If we haven't already seen the new PID stop, wait for it now. */
515 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
517 /* The new child has a pending SIGSTOP. We can't affect it until it
518 hits the SIGSTOP, but we're already attached. */
520 ret
= my_waitpid (new_pid
, &status
, __WALL
);
523 perror_with_name ("waiting for new child");
524 else if (ret
!= new_pid
)
525 warning ("wait returned unexpected PID %d", ret
);
526 else if (!WIFSTOPPED (status
))
527 warning ("wait returned unexpected status 0x%x", status
);
530 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
532 struct process_info
*parent_proc
;
533 struct process_info
*child_proc
;
534 struct lwp_info
*child_lwp
;
535 struct thread_info
*child_thr
;
537 ptid
= ptid_t (new_pid
, new_pid
);
539 threads_debug_printf ("Got fork event from LWP %ld, "
541 ptid_of (event_thr
).lwp (),
544 /* Add the new process to the tables and clone the breakpoint
545 lists of the parent. We need to do this even if the new process
546 will be detached, since we will need the process object and the
547 breakpoints to remove any breakpoints from memory when we
548 detach, and the client side will access registers. */
549 child_proc
= add_linux_process (new_pid
, 0);
550 gdb_assert (child_proc
!= NULL
);
551 child_lwp
= add_lwp (ptid
);
552 gdb_assert (child_lwp
!= NULL
);
553 child_lwp
->stopped
= 1;
554 child_lwp
->must_set_ptrace_flags
= 1;
555 child_lwp
->status_pending_p
= 0;
556 child_thr
= get_lwp_thread (child_lwp
);
557 child_thr
->last_resume_kind
= resume_stop
;
558 child_thr
->last_status
.set_stopped (GDB_SIGNAL_0
);
560 /* If we're suspending all threads, leave this one suspended
561 too. If the fork/clone parent is stepping over a breakpoint,
562 all other threads have been suspended already. Leave the
563 child suspended too. */
564 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
565 || event_lwp
->bp_reinsert
!= 0)
567 threads_debug_printf ("leaving child suspended");
568 child_lwp
->suspended
= 1;
571 parent_proc
= get_thread_process (event_thr
);
572 child_proc
->attached
= parent_proc
->attached
;
574 if (event_lwp
->bp_reinsert
!= 0
575 && supports_software_single_step ()
576 && event
== PTRACE_EVENT_VFORK
)
578 /* If we leave single-step breakpoints there, child will
579 hit it, so uninsert single-step breakpoints from parent
580 (and child). Once vfork child is done, reinsert
581 them back to parent. */
582 uninsert_single_step_breakpoints (event_thr
);
585 clone_all_breakpoints (child_thr
, event_thr
);
587 target_desc_up tdesc
= allocate_target_description ();
588 copy_target_description (tdesc
.get (), parent_proc
->tdesc
);
589 child_proc
->tdesc
= tdesc
.release ();
591 /* Clone arch-specific process data. */
592 low_new_fork (parent_proc
, child_proc
);
594 /* Save fork info in the parent thread. */
595 if (event
== PTRACE_EVENT_FORK
)
596 event_lwp
->waitstatus
.set_forked (ptid
);
597 else if (event
== PTRACE_EVENT_VFORK
)
598 event_lwp
->waitstatus
.set_vforked (ptid
);
600 /* The status_pending field contains bits denoting the
601 extended event, so when the pending event is handled,
602 the handler will look at lwp->waitstatus. */
603 event_lwp
->status_pending_p
= 1;
604 event_lwp
->status_pending
= wstat
;
606 /* Link the threads until the parent event is passed on to
608 event_lwp
->fork_relative
= child_lwp
;
609 child_lwp
->fork_relative
= event_lwp
;
611 /* If the parent thread is doing step-over with single-step
612 breakpoints, the list of single-step breakpoints are cloned
613 from the parent's. Remove them from the child process.
614 In case of vfork, we'll reinsert them back once vforked
616 if (event_lwp
->bp_reinsert
!= 0
617 && supports_software_single_step ())
619 /* The child process is forked and stopped, so it is safe
620 to access its memory without stopping all other threads
621 from other processes. */
622 delete_single_step_breakpoints (child_thr
);
624 gdb_assert (has_single_step_breakpoints (event_thr
));
625 gdb_assert (!has_single_step_breakpoints (child_thr
));
628 /* Report the event. */
633 ("Got clone event from LWP %ld, new child is LWP %ld",
634 lwpid_of (event_thr
), new_pid
);
636 ptid
= ptid_t (pid_of (event_thr
), new_pid
);
637 new_lwp
= add_lwp (ptid
);
639 /* Either we're going to immediately resume the new thread
640 or leave it stopped. resume_one_lwp is a nop if it
641 thinks the thread is currently running, so set this first
642 before calling resume_one_lwp. */
643 new_lwp
->stopped
= 1;
645 /* If we're suspending all threads, leave this one suspended
646 too. If the fork/clone parent is stepping over a breakpoint,
647 all other threads have been suspended already. Leave the
648 child suspended too. */
649 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
650 || event_lwp
->bp_reinsert
!= 0)
651 new_lwp
->suspended
= 1;
653 /* Normally we will get the pending SIGSTOP. But in some cases
654 we might get another signal delivered to the group first.
655 If we do get another signal, be sure not to lose it. */
656 if (WSTOPSIG (status
) != SIGSTOP
)
658 new_lwp
->stop_expected
= 1;
659 new_lwp
->status_pending_p
= 1;
660 new_lwp
->status_pending
= status
;
662 else if (cs
.report_thread_events
)
664 new_lwp
->waitstatus
.set_thread_created ();
665 new_lwp
->status_pending_p
= 1;
666 new_lwp
->status_pending
= status
;
670 thread_db_notice_clone (event_thr
, ptid
);
673 /* Don't report the event. */
676 else if (event
== PTRACE_EVENT_VFORK_DONE
)
678 event_lwp
->waitstatus
.set_vfork_done ();
680 if (event_lwp
->bp_reinsert
!= 0 && supports_software_single_step ())
682 reinsert_single_step_breakpoints (event_thr
);
684 gdb_assert (has_single_step_breakpoints (event_thr
));
687 /* Report the event. */
690 else if (event
== PTRACE_EVENT_EXEC
&& cs
.report_exec_events
)
692 struct process_info
*proc
;
693 std::vector
<int> syscalls_to_catch
;
697 threads_debug_printf ("Got exec event from LWP %ld",
698 lwpid_of (event_thr
));
700 /* Get the event ptid. */
701 event_ptid
= ptid_of (event_thr
);
702 event_pid
= event_ptid
.pid ();
704 /* Save the syscall list from the execing process. */
705 proc
= get_thread_process (event_thr
);
706 syscalls_to_catch
= std::move (proc
->syscalls_to_catch
);
708 /* Delete the execing process and all its threads. */
710 switch_to_thread (nullptr);
712 /* Create a new process/lwp/thread. */
713 proc
= add_linux_process (event_pid
, 0);
714 event_lwp
= add_lwp (event_ptid
);
715 event_thr
= get_lwp_thread (event_lwp
);
716 gdb_assert (current_thread
== event_thr
);
717 arch_setup_thread (event_thr
);
719 /* Set the event status. */
720 event_lwp
->waitstatus
.set_execd
722 (linux_proc_pid_to_exec_file (lwpid_of (event_thr
))));
724 /* Mark the exec status as pending. */
725 event_lwp
->stopped
= 1;
726 event_lwp
->status_pending_p
= 1;
727 event_lwp
->status_pending
= wstat
;
728 event_thr
->last_resume_kind
= resume_continue
;
729 event_thr
->last_status
.set_ignore ();
731 /* Update syscall state in the new lwp, effectively mid-syscall too. */
732 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
734 /* Restore the list to catch. Don't rely on the client, which is free
735 to avoid sending a new list when the architecture doesn't change.
736 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
737 proc
->syscalls_to_catch
= std::move (syscalls_to_catch
);
739 /* Report the event. */
740 *orig_event_lwp
= event_lwp
;
744 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
748 linux_process_target::get_pc (lwp_info
*lwp
)
750 process_info
*proc
= get_thread_process (get_lwp_thread (lwp
));
751 gdb_assert (!proc
->starting_up
);
753 if (!low_supports_breakpoints ())
756 scoped_restore_current_thread restore_thread
;
757 switch_to_thread (get_lwp_thread (lwp
));
759 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
760 CORE_ADDR pc
= low_get_pc (regcache
);
762 threads_debug_printf ("pc is 0x%lx", (long) pc
);
768 linux_process_target::get_syscall_trapinfo (lwp_info
*lwp
, int *sysno
)
770 struct regcache
*regcache
;
772 scoped_restore_current_thread restore_thread
;
773 switch_to_thread (get_lwp_thread (lwp
));
775 regcache
= get_thread_regcache (current_thread
, 1);
776 low_get_syscall_trapinfo (regcache
, sysno
);
778 threads_debug_printf ("get_syscall_trapinfo sysno %d", *sysno
);
782 linux_process_target::low_get_syscall_trapinfo (regcache
*regcache
, int *sysno
)
784 /* By default, report an unknown system call number. */
785 *sysno
= UNKNOWN_SYSCALL
;
789 linux_process_target::save_stop_reason (lwp_info
*lwp
)
792 CORE_ADDR sw_breakpoint_pc
;
793 #if USE_SIGTRAP_SIGINFO
797 if (!low_supports_breakpoints ())
800 process_info
*proc
= get_thread_process (get_lwp_thread (lwp
));
801 if (proc
->starting_up
)
803 /* Claim we have the stop PC so that the caller doesn't try to
809 sw_breakpoint_pc
= pc
- low_decr_pc_after_break ();
811 /* breakpoint_at reads from the current thread. */
812 scoped_restore_current_thread restore_thread
;
813 switch_to_thread (get_lwp_thread (lwp
));
815 #if USE_SIGTRAP_SIGINFO
816 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
817 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
819 if (siginfo
.si_signo
== SIGTRAP
)
821 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
822 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
824 /* The si_code is ambiguous on this arch -- check debug
826 if (!check_stopped_by_watchpoint (lwp
))
827 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
829 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
831 /* If we determine the LWP stopped for a SW breakpoint,
832 trust it. Particularly don't check watchpoint
833 registers, because at least on s390, we'd find
834 stopped-by-watchpoint as long as there's a watchpoint
836 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
838 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
840 /* This can indicate either a hardware breakpoint or
841 hardware watchpoint. Check debug registers. */
842 if (!check_stopped_by_watchpoint (lwp
))
843 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
845 else if (siginfo
.si_code
== TRAP_TRACE
)
847 /* We may have single stepped an instruction that
848 triggered a watchpoint. In that case, on some
849 architectures (such as x86), instead of TRAP_HWBKPT,
850 si_code indicates TRAP_TRACE, and we need to check
851 the debug registers separately. */
852 if (!check_stopped_by_watchpoint (lwp
))
853 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
858 /* We may have just stepped a breakpoint instruction. E.g., in
859 non-stop mode, GDB first tells the thread A to step a range, and
860 then the user inserts a breakpoint inside the range. In that
861 case we need to report the breakpoint PC. */
862 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
863 && low_breakpoint_at (sw_breakpoint_pc
))
864 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
866 if (hardware_breakpoint_inserted_here (pc
))
867 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
869 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
870 check_stopped_by_watchpoint (lwp
);
873 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
876 ("%s stopped by software breakpoint",
877 target_pid_to_str (ptid_of (get_lwp_thread (lwp
))).c_str ());
879 /* Back up the PC if necessary. */
880 if (pc
!= sw_breakpoint_pc
)
882 struct regcache
*regcache
883 = get_thread_regcache (current_thread
, 1);
884 low_set_pc (regcache
, sw_breakpoint_pc
);
887 /* Update this so we record the correct stop PC below. */
888 pc
= sw_breakpoint_pc
;
890 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
892 ("%s stopped by hardware breakpoint",
893 target_pid_to_str (ptid_of (get_lwp_thread (lwp
))).c_str ());
894 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
896 ("%s stopped by hardware watchpoint",
897 target_pid_to_str (ptid_of (get_lwp_thread (lwp
))).c_str ());
898 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
900 ("%s stopped by trace",
901 target_pid_to_str (ptid_of (get_lwp_thread (lwp
))).c_str ());
908 linux_process_target::add_lwp (ptid_t ptid
)
910 lwp_info
*lwp
= new lwp_info
;
912 lwp
->thread
= add_thread (ptid
, lwp
);
914 low_new_thread (lwp
);
920 linux_process_target::low_new_thread (lwp_info
*info
)
925 /* Callback to be used when calling fork_inferior, responsible for
926 actually initiating the tracing of the inferior. */
931 if (ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0,
932 (PTRACE_TYPE_ARG4
) 0) < 0)
933 trace_start_error_with_name ("ptrace");
935 if (setpgid (0, 0) < 0)
936 trace_start_error_with_name ("setpgid");
938 /* If GDBserver is connected to gdb via stdio, redirect the inferior's
939 stdout to stderr so that inferior i/o doesn't corrupt the connection.
940 Also, redirect stdin to /dev/null. */
941 if (remote_connection_is_stdio ())
944 trace_start_error_with_name ("close");
945 if (open ("/dev/null", O_RDONLY
) < 0)
946 trace_start_error_with_name ("open");
948 trace_start_error_with_name ("dup2");
949 if (write (2, "stdin/stdout redirected\n",
950 sizeof ("stdin/stdout redirected\n") - 1) < 0)
952 /* Errors ignored. */;
957 /* Start an inferior process and returns its pid.
958 PROGRAM is the name of the program to be started, and PROGRAM_ARGS
959 are its arguments. */
962 linux_process_target::create_inferior (const char *program
,
963 const std::vector
<char *> &program_args
)
965 client_state
&cs
= get_client_state ();
966 struct lwp_info
*new_lwp
;
971 maybe_disable_address_space_randomization restore_personality
972 (cs
.disable_randomization
);
973 std::string str_program_args
= construct_inferior_arguments (program_args
);
975 pid
= fork_inferior (program
,
976 str_program_args
.c_str (),
977 get_environ ()->envp (), linux_ptrace_fun
,
978 NULL
, NULL
, NULL
, NULL
);
981 /* When spawning a new process, we can't open the mem file yet. We
982 still have to nurse the process through the shell, and that execs
983 a couple times. The address space a /proc/PID/mem file is
984 accessing is destroyed on exec. */
985 process_info
*proc
= add_linux_process_no_mem_file (pid
, 0);
987 ptid
= ptid_t (pid
, pid
);
988 new_lwp
= add_lwp (ptid
);
989 new_lwp
->must_set_ptrace_flags
= 1;
991 post_fork_inferior (pid
, program
);
993 /* PROC is now past the shell running the program we want, so we can
994 open the /proc/PID/mem file. */
995 open_proc_mem_file (proc
);
1000 /* Implement the post_create_inferior target_ops method. */
1003 linux_process_target::post_create_inferior ()
1005 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
1009 if (lwp
->must_set_ptrace_flags
)
1011 struct process_info
*proc
= current_process ();
1012 int options
= linux_low_ptrace_options (proc
->attached
);
1014 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
1015 lwp
->must_set_ptrace_flags
= 0;
1020 linux_process_target::attach_lwp (ptid_t ptid
)
1022 struct lwp_info
*new_lwp
;
1023 int lwpid
= ptid
.lwp ();
1025 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
1029 new_lwp
= add_lwp (ptid
);
1031 /* We need to wait for SIGSTOP before being able to make the next
1032 ptrace call on this LWP. */
1033 new_lwp
->must_set_ptrace_flags
= 1;
1035 if (linux_proc_pid_is_stopped (lwpid
))
1037 threads_debug_printf ("Attached to a stopped process");
1039 /* The process is definitely stopped. It is in a job control
1040 stop, unless the kernel predates the TASK_STOPPED /
1041 TASK_TRACED distinction, in which case it might be in a
1042 ptrace stop. Make sure it is in a ptrace stop; from there we
1043 can kill it, signal it, et cetera.
1045 First make sure there is a pending SIGSTOP. Since we are
1046 already attached, the process can not transition from stopped
1047 to running without a PTRACE_CONT; so we know this signal will
1048 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1049 probably already in the queue (unless this kernel is old
1050 enough to use TASK_STOPPED for ptrace stops); but since
1051 SIGSTOP is not an RT signal, it can only be queued once. */
1052 kill_lwp (lwpid
, SIGSTOP
);
1054 /* Finally, resume the stopped process. This will deliver the
1055 SIGSTOP (or a higher priority signal, just like normal
1056 PTRACE_ATTACH), which we'll catch later on. */
1057 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1060 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1061 brings it to a halt.
1063 There are several cases to consider here:
1065 1) gdbserver has already attached to the process and is being notified
1066 of a new thread that is being created.
1067 In this case we should ignore that SIGSTOP and resume the
1068 process. This is handled below by setting stop_expected = 1,
1069 and the fact that add_thread sets last_resume_kind ==
1072 2) This is the first thread (the process thread), and we're attaching
1073 to it via attach_inferior.
1074 In this case we want the process thread to stop.
1075 This is handled by having linux_attach set last_resume_kind ==
1076 resume_stop after we return.
1078 If the pid we are attaching to is also the tgid, we attach to and
1079 stop all the existing threads. Otherwise, we attach to pid and
1080 ignore any other threads in the same group as this pid.
1082 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1084 In this case we want the thread to stop.
1085 FIXME: This case is currently not properly handled.
1086 We should wait for the SIGSTOP but don't. Things work apparently
1087 because enough time passes between when we ptrace (ATTACH) and when
1088 gdb makes the next ptrace call on the thread.
1090 On the other hand, if we are currently trying to stop all threads, we
1091 should treat the new thread as if we had sent it a SIGSTOP. This works
1092 because we are guaranteed that the add_lwp call above added us to the
1093 end of the list, and so the new thread has not yet reached
1094 wait_for_sigstop (but will). */
1095 new_lwp
->stop_expected
= 1;
1100 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1101 already attached. Returns true if a new LWP is found, false
1105 attach_proc_task_lwp_callback (ptid_t ptid
)
1107 /* Is this a new thread? */
1108 if (find_thread_ptid (ptid
) == NULL
)
1110 int lwpid
= ptid
.lwp ();
1113 threads_debug_printf ("Found new lwp %d", lwpid
);
1115 err
= the_linux_target
->attach_lwp (ptid
);
1117 /* Be quiet if we simply raced with the thread exiting. EPERM
1118 is returned if the thread's task still exists, and is marked
1119 as exited or zombie, as well as other conditions, so in that
1120 case, confirm the status in /proc/PID/status. */
1122 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1123 threads_debug_printf
1124 ("Cannot attach to lwp %d: thread is gone (%d: %s)",
1125 lwpid
, err
, safe_strerror (err
));
1129 = linux_ptrace_attach_fail_reason_string (ptid
, err
);
1131 warning (_("Cannot attach to lwp %d: %s"), lwpid
, reason
.c_str ());
1139 static void async_file_mark (void);
1141 /* Attach to PID. If PID is the tgid, attach to it and all
1145 linux_process_target::attach (unsigned long pid
)
1147 struct process_info
*proc
;
1148 struct thread_info
*initial_thread
;
1149 ptid_t ptid
= ptid_t (pid
, pid
);
1152 /* Delay opening the /proc/PID/mem file until we've successfully
1154 proc
= add_linux_process_no_mem_file (pid
, 1);
1156 /* Attach to PID. We will check for other threads
1158 err
= attach_lwp (ptid
);
1161 this->remove_linux_process (proc
);
1163 std::string reason
= linux_ptrace_attach_fail_reason_string (ptid
, err
);
1164 error ("Cannot attach to process %ld: %s", pid
, reason
.c_str ());
1167 open_proc_mem_file (proc
);
1169 /* Don't ignore the initial SIGSTOP if we just attached to this
1170 process. It will be collected by wait shortly. */
1171 initial_thread
= find_thread_ptid (ptid_t (pid
, pid
));
1172 initial_thread
->last_resume_kind
= resume_stop
;
1174 /* We must attach to every LWP. If /proc is mounted, use that to
1175 find them now. On the one hand, the inferior may be using raw
1176 clone instead of using pthreads. On the other hand, even if it
1177 is using pthreads, GDB may not be connected yet (thread_db needs
1178 to do symbol lookups, through qSymbol). Also, thread_db walks
1179 structures in the inferior's address space to find the list of
1180 threads/LWPs, and those structures may well be corrupted. Note
1181 that once thread_db is loaded, we'll still use it to list threads
1182 and associate pthread info with each LWP. */
1183 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1185 /* GDB will shortly read the xml target description for this
1186 process, to figure out the process' architecture. But the target
1187 description is only filled in when the first process/thread in
1188 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1189 that now, otherwise, if GDB is fast enough, it could read the
1190 target description _before_ that initial stop. */
1193 struct lwp_info
*lwp
;
1195 ptid_t pid_ptid
= ptid_t (pid
);
1197 lwpid
= wait_for_event_filtered (pid_ptid
, pid_ptid
, &wstat
, __WALL
);
1198 gdb_assert (lwpid
> 0);
1200 lwp
= find_lwp_pid (ptid_t (lwpid
));
1202 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1204 lwp
->status_pending_p
= 1;
1205 lwp
->status_pending
= wstat
;
1208 initial_thread
->last_resume_kind
= resume_continue
;
1212 gdb_assert (proc
->tdesc
!= NULL
);
1219 last_thread_of_process_p (int pid
)
1221 bool seen_one
= false;
1223 thread_info
*thread
= find_thread (pid
, [&] (thread_info
*thr_arg
)
1227 /* This is the first thread of this process we see. */
1233 /* This is the second thread of this process we see. */
1238 return thread
== NULL
;
1244 linux_kill_one_lwp (struct lwp_info
*lwp
)
1246 struct thread_info
*thr
= get_lwp_thread (lwp
);
1247 int pid
= lwpid_of (thr
);
1249 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1250 there is no signal context, and ptrace(PTRACE_KILL) (or
1251 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1252 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1253 alternative is to kill with SIGKILL. We only need one SIGKILL
1254 per process, not one for each thread. But since we still support
1255 support debugging programs using raw clone without CLONE_THREAD,
1256 we send one for each thread. For years, we used PTRACE_KILL
1257 only, so we're being a bit paranoid about some old kernels where
1258 PTRACE_KILL might work better (dubious if there are any such, but
1259 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1260 second, and so we're fine everywhere. */
1263 kill_lwp (pid
, SIGKILL
);
1266 int save_errno
= errno
;
1268 threads_debug_printf ("kill_lwp (SIGKILL) %s, 0, 0 (%s)",
1269 target_pid_to_str (ptid_of (thr
)).c_str (),
1270 save_errno
? safe_strerror (save_errno
) : "OK");
1274 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1277 int save_errno
= errno
;
1279 threads_debug_printf ("PTRACE_KILL %s, 0, 0 (%s)",
1280 target_pid_to_str (ptid_of (thr
)).c_str (),
1281 save_errno
? safe_strerror (save_errno
) : "OK");
1285 /* Kill LWP and wait for it to die. */
1288 kill_wait_lwp (struct lwp_info
*lwp
)
1290 struct thread_info
*thr
= get_lwp_thread (lwp
);
1291 int pid
= ptid_of (thr
).pid ();
1292 int lwpid
= ptid_of (thr
).lwp ();
1296 threads_debug_printf ("killing lwp %d, for pid: %d", lwpid
, pid
);
1300 linux_kill_one_lwp (lwp
);
1302 /* Make sure it died. Notes:
1304 - The loop is most likely unnecessary.
1306 - We don't use wait_for_event as that could delete lwps
1307 while we're iterating over them. We're not interested in
1308 any pending status at this point, only in making sure all
1309 wait status on the kernel side are collected until the
1312 - We don't use __WALL here as the __WALL emulation relies on
1313 SIGCHLD, and killing a stopped process doesn't generate
1314 one, nor an exit status.
1316 res
= my_waitpid (lwpid
, &wstat
, 0);
1317 if (res
== -1 && errno
== ECHILD
)
1318 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1319 } while (res
> 0 && WIFSTOPPED (wstat
));
1321 /* Even if it was stopped, the child may have already disappeared.
1322 E.g., if it was killed by SIGKILL. */
1323 if (res
< 0 && errno
!= ECHILD
)
1324 perror_with_name ("kill_wait_lwp");
1327 /* Callback for `for_each_thread'. Kills an lwp of a given process,
1328 except the leader. */
1331 kill_one_lwp_callback (thread_info
*thread
, int pid
)
1333 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1335 /* We avoid killing the first thread here, because of a Linux kernel (at
1336 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1337 the children get a chance to be reaped, it will remain a zombie
1340 if (lwpid_of (thread
) == pid
)
1342 threads_debug_printf ("is last of process %s",
1343 target_pid_to_str (thread
->id
).c_str ());
1347 kill_wait_lwp (lwp
);
1351 linux_process_target::kill (process_info
*process
)
1353 int pid
= process
->pid
;
1355 /* If we're killing a running inferior, make sure it is stopped
1356 first, as PTRACE_KILL will not work otherwise. */
1357 stop_all_lwps (0, NULL
);
1359 for_each_thread (pid
, [&] (thread_info
*thread
)
1361 kill_one_lwp_callback (thread
, pid
);
1364 /* See the comment in linux_kill_one_lwp. We did not kill the first
1365 thread in the list, so do so now. */
1366 lwp_info
*lwp
= find_lwp_pid (ptid_t (pid
));
1369 threads_debug_printf ("cannot find lwp for pid: %d", pid
);
1371 kill_wait_lwp (lwp
);
1375 /* Since we presently can only stop all lwps of all processes, we
1376 need to unstop lwps of other processes. */
1377 unstop_all_lwps (0, NULL
);
1381 /* Get pending signal of THREAD, for detaching purposes. This is the
1382 signal the thread last stopped for, which we need to deliver to the
1383 thread when detaching, otherwise, it'd be suppressed/lost. */
1386 get_detach_signal (struct thread_info
*thread
)
1388 client_state
&cs
= get_client_state ();
1389 enum gdb_signal signo
= GDB_SIGNAL_0
;
1391 struct lwp_info
*lp
= get_thread_lwp (thread
);
1393 if (lp
->status_pending_p
)
1394 status
= lp
->status_pending
;
1397 /* If the thread had been suspended by gdbserver, and it stopped
1398 cleanly, then it'll have stopped with SIGSTOP. But we don't
1399 want to deliver that SIGSTOP. */
1400 if (thread
->last_status
.kind () != TARGET_WAITKIND_STOPPED
1401 || thread
->last_status
.sig () == GDB_SIGNAL_0
)
1404 /* Otherwise, we may need to deliver the signal we
1406 status
= lp
->last_status
;
1409 if (!WIFSTOPPED (status
))
1411 threads_debug_printf ("lwp %s hasn't stopped: no pending signal",
1412 target_pid_to_str (ptid_of (thread
)).c_str ());
1416 /* Extended wait statuses aren't real SIGTRAPs. */
1417 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1419 threads_debug_printf ("lwp %s had stopped with extended "
1420 "status: no pending signal",
1421 target_pid_to_str (ptid_of (thread
)).c_str ());
1425 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1427 if (cs
.program_signals_p
&& !cs
.program_signals
[signo
])
1429 threads_debug_printf ("lwp %s had signal %s, but it is in nopass state",
1430 target_pid_to_str (ptid_of (thread
)).c_str (),
1431 gdb_signal_to_string (signo
));
1434 else if (!cs
.program_signals_p
1435 /* If we have no way to know which signals GDB does not
1436 want to have passed to the program, assume
1437 SIGTRAP/SIGINT, which is GDB's default. */
1438 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1440 threads_debug_printf ("lwp %s had signal %s, "
1441 "but we don't know if we should pass it. "
1443 target_pid_to_str (ptid_of (thread
)).c_str (),
1444 gdb_signal_to_string (signo
));
1449 threads_debug_printf ("lwp %s has pending signal %s: delivering it",
1450 target_pid_to_str (ptid_of (thread
)).c_str (),
1451 gdb_signal_to_string (signo
));
1453 return WSTOPSIG (status
);
1458 linux_process_target::detach_one_lwp (lwp_info
*lwp
)
1460 struct thread_info
*thread
= get_lwp_thread (lwp
);
1464 /* If there is a pending SIGSTOP, get rid of it. */
1465 if (lwp
->stop_expected
)
1467 threads_debug_printf ("Sending SIGCONT to %s",
1468 target_pid_to_str (ptid_of (thread
)).c_str ());
1470 kill_lwp (lwpid_of (thread
), SIGCONT
);
1471 lwp
->stop_expected
= 0;
1474 /* Pass on any pending signal for this thread. */
1475 sig
= get_detach_signal (thread
);
1477 /* Preparing to resume may try to write registers, and fail if the
1478 lwp is zombie. If that happens, ignore the error. We'll handle
1479 it below, when detach fails with ESRCH. */
1482 /* Flush any pending changes to the process's registers. */
1483 regcache_invalidate_thread (thread
);
1485 /* Finally, let it resume. */
1486 low_prepare_to_resume (lwp
);
1488 catch (const gdb_exception_error
&ex
)
1490 if (!check_ptrace_stopped_lwp_gone (lwp
))
1494 lwpid
= lwpid_of (thread
);
1495 if (ptrace (PTRACE_DETACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0,
1496 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1498 int save_errno
= errno
;
1500 /* We know the thread exists, so ESRCH must mean the lwp is
1501 zombie. This can happen if one of the already-detached
1502 threads exits the whole thread group. In that case we're
1503 still attached, and must reap the lwp. */
1504 if (save_errno
== ESRCH
)
1508 ret
= my_waitpid (lwpid
, &status
, __WALL
);
1511 warning (_("Couldn't reap LWP %d while detaching: %s"),
1512 lwpid
, safe_strerror (errno
));
1514 else if (!WIFEXITED (status
) && !WIFSIGNALED (status
))
1516 warning (_("Reaping LWP %d while detaching "
1517 "returned unexpected status 0x%x"),
1523 error (_("Can't detach %s: %s"),
1524 target_pid_to_str (ptid_of (thread
)).c_str (),
1525 safe_strerror (save_errno
));
1529 threads_debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)",
1530 target_pid_to_str (ptid_of (thread
)).c_str (),
1537 linux_process_target::detach (process_info
*process
)
1539 struct lwp_info
*main_lwp
;
1541 /* As there's a step over already in progress, let it finish first,
1542 otherwise nesting a stabilize_threads operation on top gets real
1544 complete_ongoing_step_over ();
1546 /* Stop all threads before detaching. First, ptrace requires that
1547 the thread is stopped to successfully detach. Second, thread_db
1548 may need to uninstall thread event breakpoints from memory, which
1549 only works with a stopped process anyway. */
1550 stop_all_lwps (0, NULL
);
1552 #ifdef USE_THREAD_DB
1553 thread_db_detach (process
);
1556 /* Stabilize threads (move out of jump pads). */
1557 target_stabilize_threads ();
1559 /* Detach from the clone lwps first. If the thread group exits just
1560 while we're detaching, we must reap the clone lwps before we're
1561 able to reap the leader. */
1562 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1564 /* We don't actually detach from the thread group leader just yet.
1565 If the thread group exits, we must reap the zombie clone lwps
1566 before we're able to reap the leader. */
1567 if (thread
->id
.pid () == thread
->id
.lwp ())
1570 lwp_info
*lwp
= get_thread_lwp (thread
);
1571 detach_one_lwp (lwp
);
1574 main_lwp
= find_lwp_pid (ptid_t (process
->pid
));
1575 detach_one_lwp (main_lwp
);
1579 /* Since we presently can only stop all lwps of all processes, we
1580 need to unstop lwps of other processes. */
1581 unstop_all_lwps (0, NULL
);
1585 /* Remove all LWPs that belong to process PROC from the lwp list. */
1588 linux_process_target::mourn (process_info
*process
)
1590 #ifdef USE_THREAD_DB
1591 thread_db_mourn (process
);
1594 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1596 delete_lwp (get_thread_lwp (thread
));
1599 this->remove_linux_process (process
);
1603 linux_process_target::join (int pid
)
1608 ret
= my_waitpid (pid
, &status
, 0);
1609 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1611 } while (ret
!= -1 || errno
!= ECHILD
);
1614 /* Return true if the given thread is still alive. */
1617 linux_process_target::thread_alive (ptid_t ptid
)
1619 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1621 /* We assume we always know if a thread exits. If a whole process
1622 exited but we still haven't been able to report it to GDB, we'll
1623 hold on to the last lwp of the dead process. */
1625 return !lwp_is_marked_dead (lwp
);
1631 linux_process_target::thread_still_has_status_pending (thread_info
*thread
)
1633 struct lwp_info
*lp
= get_thread_lwp (thread
);
1635 if (!lp
->status_pending_p
)
1638 if (thread
->last_resume_kind
!= resume_stop
1639 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1640 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1645 gdb_assert (lp
->last_status
!= 0);
1649 scoped_restore_current_thread restore_thread
;
1650 switch_to_thread (thread
);
1652 if (pc
!= lp
->stop_pc
)
1654 threads_debug_printf ("PC of %ld changed",
1659 #if !USE_SIGTRAP_SIGINFO
1660 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1661 && !low_breakpoint_at (pc
))
1663 threads_debug_printf ("previous SW breakpoint of %ld gone",
1667 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1668 && !hardware_breakpoint_inserted_here (pc
))
1670 threads_debug_printf ("previous HW breakpoint of %ld gone",
1678 threads_debug_printf ("discarding pending breakpoint status");
1679 lp
->status_pending_p
= 0;
1687 /* Returns true if LWP is resumed from the client's perspective. */
1690 lwp_resumed (struct lwp_info
*lwp
)
1692 struct thread_info
*thread
= get_lwp_thread (lwp
);
1694 if (thread
->last_resume_kind
!= resume_stop
)
1697 /* Did gdb send us a `vCont;t', but we haven't reported the
1698 corresponding stop to gdb yet? If so, the thread is still
1699 resumed/running from gdb's perspective. */
1700 if (thread
->last_resume_kind
== resume_stop
1701 && thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
)
1708 linux_process_target::status_pending_p_callback (thread_info
*thread
,
1711 struct lwp_info
*lp
= get_thread_lwp (thread
);
1713 /* Check if we're only interested in events from a specific process
1714 or a specific LWP. */
1715 if (!thread
->id
.matches (ptid
))
1718 if (!lwp_resumed (lp
))
1721 if (lp
->status_pending_p
1722 && !thread_still_has_status_pending (thread
))
1724 resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1728 return lp
->status_pending_p
;
1732 find_lwp_pid (ptid_t ptid
)
1734 thread_info
*thread
= find_thread ([&] (thread_info
*thr_arg
)
1736 int lwp
= ptid
.lwp () != 0 ? ptid
.lwp () : ptid
.pid ();
1737 return thr_arg
->id
.lwp () == lwp
;
1743 return get_thread_lwp (thread
);
1746 /* Return the number of known LWPs in the tgid given by PID. */
1753 for_each_thread (pid
, [&] (thread_info
*thread
)
1761 /* See nat/linux-nat.h. */
1764 iterate_over_lwps (ptid_t filter
,
1765 gdb::function_view
<iterate_over_lwps_ftype
> callback
)
1767 thread_info
*thread
= find_thread (filter
, [&] (thread_info
*thr_arg
)
1769 lwp_info
*lwp
= get_thread_lwp (thr_arg
);
1771 return callback (lwp
);
1777 return get_thread_lwp (thread
);
1781 linux_process_target::check_zombie_leaders ()
1783 for_each_process ([this] (process_info
*proc
)
1785 pid_t leader_pid
= pid_of (proc
);
1786 lwp_info
*leader_lp
= find_lwp_pid (ptid_t (leader_pid
));
1788 threads_debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1789 "num_lwps=%d, zombie=%d",
1790 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1791 linux_proc_pid_is_zombie (leader_pid
));
1793 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1794 /* Check if there are other threads in the group, as we may
1795 have raced with the inferior simply exiting. Note this
1796 isn't a watertight check. If the inferior is
1797 multi-threaded and is exiting, it may be we see the
1798 leader as zombie before we reap all the non-leader
1799 threads. See comments below. */
1800 && !last_thread_of_process_p (leader_pid
)
1801 && linux_proc_pid_is_zombie (leader_pid
))
1803 /* A zombie leader in a multi-threaded program can mean one
1806 #1 - Only the leader exited, not the whole program, e.g.,
1807 with pthread_exit. Since we can't reap the leader's exit
1808 status until all other threads are gone and reaped too,
1809 we want to delete the zombie leader right away, as it
1810 can't be debugged, we can't read its registers, etc.
1811 This is the main reason we check for zombie leaders
1814 #2 - The whole thread-group/process exited (a group exit,
1815 via e.g. exit(3), and there is (or will be shortly) an
1816 exit reported for each thread in the process, and then
1817 finally an exit for the leader once the non-leaders are
1820 #3 - There are 3 or more threads in the group, and a
1821 thread other than the leader exec'd. See comments on
1822 exec events at the top of the file.
1824 Ideally we would never delete the leader for case #2.
1825 Instead, we want to collect the exit status of each
1826 non-leader thread, and then finally collect the exit
1827 status of the leader as normal and use its exit code as
1828 whole-process exit code. Unfortunately, there's no
1829 race-free way to distinguish cases #1 and #2. We can't
1830 assume the exit events for the non-leaders threads are
1831 already pending in the kernel, nor can we assume the
1832 non-leader threads are in zombie state already. Between
1833 the leader becoming zombie and the non-leaders exiting
1834 and becoming zombie themselves, there's a small time
1835 window, so such a check would be racy. Temporarily
1836 pausing all threads and checking to see if all threads
1837 exit or not before re-resuming them would work in the
1838 case that all threads are running right now, but it
1839 wouldn't work if some thread is currently already
1840 ptrace-stopped, e.g., due to scheduler-locking.
1842 So what we do is we delete the leader anyhow, and then
1843 later on when we see its exit status, we re-add it back.
1844 We also make sure that we only report a whole-process
1845 exit when we see the leader exiting, as opposed to when
1846 the last LWP in the LWP list exits, which can be a
1847 non-leader if we deleted the leader here. */
1848 threads_debug_printf ("Thread group leader %d zombie "
1849 "(it exited, or another thread execd), "
1852 delete_lwp (leader_lp
);
1857 /* Callback for `find_thread'. Returns the first LWP that is not
1861 not_stopped_callback (thread_info
*thread
, ptid_t filter
)
1863 if (!thread
->id
.matches (filter
))
1866 lwp_info
*lwp
= get_thread_lwp (thread
);
1868 return !lwp
->stopped
;
1871 /* Increment LWP's suspend count. */
1874 lwp_suspended_inc (struct lwp_info
*lwp
)
1878 if (lwp
->suspended
> 4)
1879 threads_debug_printf
1880 ("LWP %ld has a suspiciously high suspend count, suspended=%d",
1881 lwpid_of (get_lwp_thread (lwp
)), lwp
->suspended
);
1884 /* Decrement LWP's suspend count. */
1887 lwp_suspended_decr (struct lwp_info
*lwp
)
1891 if (lwp
->suspended
< 0)
1893 struct thread_info
*thread
= get_lwp_thread (lwp
);
1895 internal_error (__FILE__
, __LINE__
,
1896 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1901 /* This function should only be called if the LWP got a SIGTRAP.
1903 Handle any tracepoint steps or hits. Return true if a tracepoint
1904 event was handled, 0 otherwise. */
1907 handle_tracepoints (struct lwp_info
*lwp
)
1909 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1910 int tpoint_related_event
= 0;
1912 gdb_assert (lwp
->suspended
== 0);
1914 /* If this tracepoint hit causes a tracing stop, we'll immediately
1915 uninsert tracepoints. To do this, we temporarily pause all
1916 threads, unpatch away, and then unpause threads. We need to make
1917 sure the unpausing doesn't resume LWP too. */
1918 lwp_suspended_inc (lwp
);
1920 /* And we need to be sure that any all-threads-stopping doesn't try
1921 to move threads out of the jump pads, as it could deadlock the
1922 inferior (LWP could be in the jump pad, maybe even holding the
1925 /* Do any necessary step collect actions. */
1926 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1928 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1930 /* See if we just hit a tracepoint and do its main collect
1932 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1934 lwp_suspended_decr (lwp
);
1936 gdb_assert (lwp
->suspended
== 0);
1937 gdb_assert (!stabilizing_threads
1938 || (lwp
->collecting_fast_tracepoint
1939 != fast_tpoint_collect_result::not_collecting
));
1941 if (tpoint_related_event
)
1943 threads_debug_printf ("got a tracepoint event");
1950 fast_tpoint_collect_result
1951 linux_process_target::linux_fast_tracepoint_collecting
1952 (lwp_info
*lwp
, fast_tpoint_collect_status
*status
)
1954 CORE_ADDR thread_area
;
1955 struct thread_info
*thread
= get_lwp_thread (lwp
);
1957 /* Get the thread area address. This is used to recognize which
1958 thread is which when tracing with the in-process agent library.
1959 We don't read anything from the address, and treat it as opaque;
1960 it's the address itself that we assume is unique per-thread. */
1961 if (low_get_thread_area (lwpid_of (thread
), &thread_area
) == -1)
1962 return fast_tpoint_collect_result::not_collecting
;
1964 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1968 linux_process_target::low_get_thread_area (int lwpid
, CORE_ADDR
*addrp
)
1974 linux_process_target::maybe_move_out_of_jump_pad (lwp_info
*lwp
, int *wstat
)
1976 scoped_restore_current_thread restore_thread
;
1977 switch_to_thread (get_lwp_thread (lwp
));
1980 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1981 && supports_fast_tracepoints ()
1982 && agent_loaded_p ())
1984 struct fast_tpoint_collect_status status
;
1986 threads_debug_printf
1987 ("Checking whether LWP %ld needs to move out of the jump pad.",
1988 lwpid_of (current_thread
));
1990 fast_tpoint_collect_result r
1991 = linux_fast_tracepoint_collecting (lwp
, &status
);
1994 || (WSTOPSIG (*wstat
) != SIGILL
1995 && WSTOPSIG (*wstat
) != SIGFPE
1996 && WSTOPSIG (*wstat
) != SIGSEGV
1997 && WSTOPSIG (*wstat
) != SIGBUS
))
1999 lwp
->collecting_fast_tracepoint
= r
;
2001 if (r
!= fast_tpoint_collect_result::not_collecting
)
2003 if (r
== fast_tpoint_collect_result::before_insn
2004 && lwp
->exit_jump_pad_bkpt
== NULL
)
2006 /* Haven't executed the original instruction yet.
2007 Set breakpoint there, and wait till it's hit,
2008 then single-step until exiting the jump pad. */
2009 lwp
->exit_jump_pad_bkpt
2010 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2013 threads_debug_printf
2014 ("Checking whether LWP %ld needs to move out of the jump pad..."
2015 " it does", lwpid_of (current_thread
));
2022 /* If we get a synchronous signal while collecting, *and*
2023 while executing the (relocated) original instruction,
2024 reset the PC to point at the tpoint address, before
2025 reporting to GDB. Otherwise, it's an IPA lib bug: just
2026 report the signal to GDB, and pray for the best. */
2028 lwp
->collecting_fast_tracepoint
2029 = fast_tpoint_collect_result::not_collecting
;
2031 if (r
!= fast_tpoint_collect_result::not_collecting
2032 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2033 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2036 struct regcache
*regcache
;
2038 /* The si_addr on a few signals references the address
2039 of the faulting instruction. Adjust that as
2041 if ((WSTOPSIG (*wstat
) == SIGILL
2042 || WSTOPSIG (*wstat
) == SIGFPE
2043 || WSTOPSIG (*wstat
) == SIGBUS
2044 || WSTOPSIG (*wstat
) == SIGSEGV
)
2045 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2046 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2047 /* Final check just to make sure we don't clobber
2048 the siginfo of non-kernel-sent signals. */
2049 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2051 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2052 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2053 (PTRACE_TYPE_ARG3
) 0, &info
);
2056 regcache
= get_thread_regcache (current_thread
, 1);
2057 low_set_pc (regcache
, status
.tpoint_addr
);
2058 lwp
->stop_pc
= status
.tpoint_addr
;
2060 /* Cancel any fast tracepoint lock this thread was
2062 force_unlock_trace_buffer ();
2065 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2067 threads_debug_printf
2068 ("Cancelling fast exit-jump-pad: removing bkpt."
2069 "stopping all threads momentarily.");
2071 stop_all_lwps (1, lwp
);
2073 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2074 lwp
->exit_jump_pad_bkpt
= NULL
;
2076 unstop_all_lwps (1, lwp
);
2078 gdb_assert (lwp
->suspended
>= 0);
2083 threads_debug_printf
2084 ("Checking whether LWP %ld needs to move out of the jump pad... no",
2085 lwpid_of (current_thread
));
2090 /* Enqueue one signal in the "signals to report later when out of the
2094 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2096 struct thread_info
*thread
= get_lwp_thread (lwp
);
2098 threads_debug_printf ("Deferring signal %d for LWP %ld.",
2099 WSTOPSIG (*wstat
), lwpid_of (thread
));
2103 for (const auto &sig
: lwp
->pending_signals_to_report
)
2104 threads_debug_printf (" Already queued %d", sig
.signal
);
2106 threads_debug_printf (" (no more currently queued signals)");
2109 /* Don't enqueue non-RT signals if they are already in the deferred
2110 queue. (SIGSTOP being the easiest signal to see ending up here
2112 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2114 for (const auto &sig
: lwp
->pending_signals_to_report
)
2116 if (sig
.signal
== WSTOPSIG (*wstat
))
2118 threads_debug_printf
2119 ("Not requeuing already queued non-RT signal %d for LWP %ld",
2120 sig
.signal
, lwpid_of (thread
));
2126 lwp
->pending_signals_to_report
.emplace_back (WSTOPSIG (*wstat
));
2128 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2129 &lwp
->pending_signals_to_report
.back ().info
);
2132 /* Dequeue one signal from the "signals to report later when out of
2133 the jump pad" list. */
2136 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2138 struct thread_info
*thread
= get_lwp_thread (lwp
);
2140 if (!lwp
->pending_signals_to_report
.empty ())
2142 const pending_signal
&p_sig
= lwp
->pending_signals_to_report
.front ();
2144 *wstat
= W_STOPCODE (p_sig
.signal
);
2145 if (p_sig
.info
.si_signo
!= 0)
2146 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2149 lwp
->pending_signals_to_report
.pop_front ();
2151 threads_debug_printf ("Reporting deferred signal %d for LWP %ld.",
2152 WSTOPSIG (*wstat
), lwpid_of (thread
));
2156 for (const auto &sig
: lwp
->pending_signals_to_report
)
2157 threads_debug_printf (" Still queued %d", sig
.signal
);
2159 threads_debug_printf (" (no more queued signals)");
2169 linux_process_target::check_stopped_by_watchpoint (lwp_info
*child
)
2171 scoped_restore_current_thread restore_thread
;
2172 switch_to_thread (get_lwp_thread (child
));
2174 if (low_stopped_by_watchpoint ())
2176 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2177 child
->stopped_data_address
= low_stopped_data_address ();
2180 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2184 linux_process_target::low_stopped_by_watchpoint ()
2190 linux_process_target::low_stopped_data_address ()
2195 /* Return the ptrace options that we want to try to enable. */
2198 linux_low_ptrace_options (int attached
)
2200 client_state
&cs
= get_client_state ();
2204 options
|= PTRACE_O_EXITKILL
;
2206 if (cs
.report_fork_events
)
2207 options
|= PTRACE_O_TRACEFORK
;
2209 if (cs
.report_vfork_events
)
2210 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2212 if (cs
.report_exec_events
)
2213 options
|= PTRACE_O_TRACEEXEC
;
2215 options
|= PTRACE_O_TRACESYSGOOD
;
2221 linux_process_target::filter_event (int lwpid
, int wstat
)
2223 client_state
&cs
= get_client_state ();
2224 struct lwp_info
*child
;
2225 struct thread_info
*thread
;
2226 int have_stop_pc
= 0;
2228 child
= find_lwp_pid (ptid_t (lwpid
));
2230 /* Check for events reported by anything not in our LWP list. */
2231 if (child
== nullptr)
2233 if (WIFSTOPPED (wstat
))
2235 if (WSTOPSIG (wstat
) == SIGTRAP
2236 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2238 /* A non-leader thread exec'ed after we've seen the
2239 leader zombie, and removed it from our lists (in
2240 check_zombie_leaders). The non-leader thread changes
2241 its tid to the tgid. */
2242 threads_debug_printf
2243 ("Re-adding thread group leader LWP %d after exec.",
2246 child
= add_lwp (ptid_t (lwpid
, lwpid
));
2248 switch_to_thread (child
->thread
);
2252 /* A process we are controlling has forked and the new
2253 child's stop was reported to us by the kernel. Save
2254 its PID and go back to waiting for the fork event to
2255 be reported - the stopped process might be returned
2256 from waitpid before or after the fork event is. */
2257 threads_debug_printf
2258 ("Saving LWP %d status %s in stopped_pids list",
2259 lwpid
, status_to_str (wstat
).c_str ());
2260 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2265 /* Don't report an event for the exit of an LWP not in our
2266 list, i.e. not part of any inferior we're debugging.
2267 This can happen if we detach from a program we originally
2268 forked and then it exits. However, note that we may have
2269 earlier deleted a leader of an inferior we're debugging,
2270 in check_zombie_leaders. Re-add it back here if so. */
2271 find_process ([&] (process_info
*proc
)
2273 if (proc
->pid
== lwpid
)
2275 threads_debug_printf
2276 ("Re-adding thread group leader LWP %d after exit.",
2279 child
= add_lwp (ptid_t (lwpid
, lwpid
));
2286 if (child
== nullptr)
2290 thread
= get_lwp_thread (child
);
2294 child
->last_status
= wstat
;
2296 /* Check if the thread has exited. */
2297 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2299 threads_debug_printf ("%d exited", lwpid
);
2301 if (finish_step_over (child
))
2303 /* Unsuspend all other LWPs, and set them back running again. */
2304 unsuspend_all_lwps (child
);
2307 /* If this is not the leader LWP, then the exit signal was not
2308 the end of the debugged application and should be ignored,
2309 unless GDB wants to hear about thread exits. */
2310 if (cs
.report_thread_events
|| is_leader (thread
))
2312 /* Since events are serialized to GDB core, and we can't
2313 report this one right now. Leave the status pending for
2314 the next time we're able to report it. */
2315 mark_lwp_dead (child
, wstat
);
2325 gdb_assert (WIFSTOPPED (wstat
));
2327 if (WIFSTOPPED (wstat
))
2329 struct process_info
*proc
;
2331 /* Architecture-specific setup after inferior is running. */
2332 proc
= find_process_pid (pid_of (thread
));
2333 if (proc
->tdesc
== NULL
)
2337 /* This needs to happen after we have attached to the
2338 inferior and it is stopped for the first time, but
2339 before we access any inferior registers. */
2340 arch_setup_thread (thread
);
2344 /* The process is started, but GDBserver will do
2345 architecture-specific setup after the program stops at
2346 the first instruction. */
2347 child
->status_pending_p
= 1;
2348 child
->status_pending
= wstat
;
2354 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2356 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2357 int options
= linux_low_ptrace_options (proc
->attached
);
2359 linux_enable_event_reporting (lwpid
, options
);
2360 child
->must_set_ptrace_flags
= 0;
2363 /* Always update syscall_state, even if it will be filtered later. */
2364 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2366 child
->syscall_state
2367 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2368 ? TARGET_WAITKIND_SYSCALL_RETURN
2369 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2373 /* Almost all other ptrace-stops are known to be outside of system
2374 calls, with further exceptions in handle_extended_wait. */
2375 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2378 /* Be careful to not overwrite stop_pc until save_stop_reason is
2380 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2381 && linux_is_extended_waitstatus (wstat
))
2383 child
->stop_pc
= get_pc (child
);
2384 if (handle_extended_wait (&child
, wstat
))
2386 /* The event has been handled, so just return without
2392 if (linux_wstatus_maybe_breakpoint (wstat
))
2394 if (save_stop_reason (child
))
2399 child
->stop_pc
= get_pc (child
);
2401 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2402 && child
->stop_expected
)
2404 threads_debug_printf ("Expected stop.");
2406 child
->stop_expected
= 0;
2408 if (thread
->last_resume_kind
== resume_stop
)
2410 /* We want to report the stop to the core. Treat the
2411 SIGSTOP as a normal event. */
2412 threads_debug_printf ("resume_stop SIGSTOP caught for %s.",
2413 target_pid_to_str (ptid_of (thread
)).c_str ());
2415 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2417 /* Stopping threads. We don't want this SIGSTOP to end up
2419 threads_debug_printf ("SIGSTOP caught for %s while stopping threads.",
2420 target_pid_to_str (ptid_of (thread
)).c_str ());
2425 /* This is a delayed SIGSTOP. Filter out the event. */
2426 threads_debug_printf ("%s %s, 0, 0 (discard delayed SIGSTOP)",
2427 child
->stepping
? "step" : "continue",
2428 target_pid_to_str (ptid_of (thread
)).c_str ());
2430 resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2435 child
->status_pending_p
= 1;
2436 child
->status_pending
= wstat
;
2441 linux_process_target::maybe_hw_step (thread_info
*thread
)
2443 if (supports_hardware_single_step ())
2447 /* GDBserver must insert single-step breakpoint for software
2449 gdb_assert (has_single_step_breakpoints (thread
));
2455 linux_process_target::resume_stopped_resumed_lwps (thread_info
*thread
)
2457 struct lwp_info
*lp
= get_thread_lwp (thread
);
2461 && !lp
->status_pending_p
2462 && thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
)
2466 if (thread
->last_resume_kind
== resume_step
)
2467 step
= maybe_hw_step (thread
);
2469 threads_debug_printf ("resuming stopped-resumed LWP %s at %s: step=%d",
2470 target_pid_to_str (ptid_of (thread
)).c_str (),
2471 paddress (lp
->stop_pc
), step
);
2473 resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2478 linux_process_target::wait_for_event_filtered (ptid_t wait_ptid
,
2480 int *wstatp
, int options
)
2482 struct thread_info
*event_thread
;
2483 struct lwp_info
*event_child
, *requested_child
;
2484 sigset_t block_mask
, prev_mask
;
2487 /* N.B. event_thread points to the thread_info struct that contains
2488 event_child. Keep them in sync. */
2489 event_thread
= NULL
;
2491 requested_child
= NULL
;
2493 /* Check for a lwp with a pending status. */
2495 if (filter_ptid
== minus_one_ptid
|| filter_ptid
.is_pid ())
2497 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2499 return status_pending_p_callback (thread
, filter_ptid
);
2502 if (event_thread
!= NULL
)
2504 event_child
= get_thread_lwp (event_thread
);
2505 threads_debug_printf ("Got a pending child %ld", lwpid_of (event_thread
));
2508 else if (filter_ptid
!= null_ptid
)
2510 requested_child
= find_lwp_pid (filter_ptid
);
2512 if (stopping_threads
== NOT_STOPPING_THREADS
2513 && requested_child
->status_pending_p
2514 && (requested_child
->collecting_fast_tracepoint
2515 != fast_tpoint_collect_result::not_collecting
))
2517 enqueue_one_deferred_signal (requested_child
,
2518 &requested_child
->status_pending
);
2519 requested_child
->status_pending_p
= 0;
2520 requested_child
->status_pending
= 0;
2521 resume_one_lwp (requested_child
, 0, 0, NULL
);
2524 if (requested_child
->suspended
2525 && requested_child
->status_pending_p
)
2527 internal_error (__FILE__
, __LINE__
,
2528 "requesting an event out of a"
2529 " suspended child?");
2532 if (requested_child
->status_pending_p
)
2534 event_child
= requested_child
;
2535 event_thread
= get_lwp_thread (event_child
);
2539 if (event_child
!= NULL
)
2541 threads_debug_printf ("Got an event from pending child %ld (%04x)",
2542 lwpid_of (event_thread
),
2543 event_child
->status_pending
);
2545 *wstatp
= event_child
->status_pending
;
2546 event_child
->status_pending_p
= 0;
2547 event_child
->status_pending
= 0;
2548 switch_to_thread (event_thread
);
2549 return lwpid_of (event_thread
);
2552 /* But if we don't find a pending event, we'll have to wait.
2554 We only enter this loop if no process has a pending wait status.
2555 Thus any action taken in response to a wait status inside this
2556 loop is responding as soon as we detect the status, not after any
2559 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2560 all signals while here. */
2561 sigfillset (&block_mask
);
2562 gdb_sigmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2564 /* Always pull all events out of the kernel. We'll randomly select
2565 an event LWP out of all that have events, to prevent
2567 while (event_child
== NULL
)
2571 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2574 - If the thread group leader exits while other threads in the
2575 thread group still exist, waitpid(TGID, ...) hangs. That
2576 waitpid won't return an exit status until the other threads
2577 in the group are reaped.
2579 - When a non-leader thread execs, that thread just vanishes
2580 without reporting an exit (so we'd hang if we waited for it
2581 explicitly in that case). The exec event is reported to
2584 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2586 threads_debug_printf ("waitpid(-1, ...) returned %d, %s",
2587 ret
, errno
? safe_strerror (errno
) : "ERRNO-OK");
2591 threads_debug_printf ("waitpid %ld received %s",
2592 (long) ret
, status_to_str (*wstatp
).c_str ());
2594 /* Filter all events. IOW, leave all events pending. We'll
2595 randomly select an event LWP out of all that have events
2597 filter_event (ret
, *wstatp
);
2598 /* Retry until nothing comes out of waitpid. A single
2599 SIGCHLD can indicate more than one child stopped. */
2603 /* Now that we've pulled all events out of the kernel, resume
2604 LWPs that don't have an interesting event to report. */
2605 if (stopping_threads
== NOT_STOPPING_THREADS
)
2606 for_each_thread ([this] (thread_info
*thread
)
2608 resume_stopped_resumed_lwps (thread
);
2611 /* ... and find an LWP with a status to report to the core, if
2613 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2615 return status_pending_p_callback (thread
, filter_ptid
);
2618 if (event_thread
!= NULL
)
2620 event_child
= get_thread_lwp (event_thread
);
2621 *wstatp
= event_child
->status_pending
;
2622 event_child
->status_pending_p
= 0;
2623 event_child
->status_pending
= 0;
2627 /* Check for zombie thread group leaders. Those can't be reaped
2628 until all other threads in the thread group are. */
2629 check_zombie_leaders ();
2631 auto not_stopped
= [&] (thread_info
*thread
)
2633 return not_stopped_callback (thread
, wait_ptid
);
2636 /* If there are no resumed children left in the set of LWPs we
2637 want to wait for, bail. We can't just block in
2638 waitpid/sigsuspend, because lwps might have been left stopped
2639 in trace-stop state, and we'd be stuck forever waiting for
2640 their status to change (which would only happen if we resumed
2641 them). Even if WNOHANG is set, this return code is preferred
2642 over 0 (below), as it is more detailed. */
2643 if (find_thread (not_stopped
) == NULL
)
2645 threads_debug_printf ("exit (no unwaited-for LWP)");
2647 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2651 /* No interesting event to report to the caller. */
2652 if ((options
& WNOHANG
))
2654 threads_debug_printf ("WNOHANG set, no event found");
2656 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2660 /* Block until we get an event reported with SIGCHLD. */
2661 threads_debug_printf ("sigsuspend'ing");
2663 sigsuspend (&prev_mask
);
2664 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2668 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2670 switch_to_thread (event_thread
);
2672 return lwpid_of (event_thread
);
2676 linux_process_target::wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2678 return wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2681 /* Select one LWP out of those that have events pending. */
2684 select_event_lwp (struct lwp_info
**orig_lp
)
2686 struct thread_info
*event_thread
= NULL
;
2688 /* In all-stop, give preference to the LWP that is being
2689 single-stepped. There will be at most one, and it's the LWP that
2690 the core is most interested in. If we didn't do this, then we'd
2691 have to handle pending step SIGTRAPs somehow in case the core
2692 later continues the previously-stepped thread, otherwise we'd
2693 report the pending SIGTRAP, and the core, not having stepped the
2694 thread, wouldn't understand what the trap was for, and therefore
2695 would report it to the user as a random signal. */
2698 event_thread
= find_thread ([] (thread_info
*thread
)
2700 lwp_info
*lp
= get_thread_lwp (thread
);
2702 return (thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
2703 && thread
->last_resume_kind
== resume_step
2704 && lp
->status_pending_p
);
2707 if (event_thread
!= NULL
)
2708 threads_debug_printf
2709 ("Select single-step %s",
2710 target_pid_to_str (ptid_of (event_thread
)).c_str ());
2712 if (event_thread
== NULL
)
2714 /* No single-stepping LWP. Select one at random, out of those
2715 which have had events. */
2717 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2719 lwp_info
*lp
= get_thread_lwp (thread
);
2721 /* Only resumed LWPs that have an event pending. */
2722 return (thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
2723 && lp
->status_pending_p
);
2727 if (event_thread
!= NULL
)
2729 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2731 /* Switch the event LWP. */
2732 *orig_lp
= event_lp
;
2736 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2740 unsuspend_all_lwps (struct lwp_info
*except
)
2742 for_each_thread ([&] (thread_info
*thread
)
2744 lwp_info
*lwp
= get_thread_lwp (thread
);
2747 lwp_suspended_decr (lwp
);
2751 static bool lwp_running (thread_info
*thread
);
2753 /* Stabilize threads (move out of jump pads).
2755 If a thread is midway collecting a fast tracepoint, we need to
2756 finish the collection and move it out of the jump pad before
2757 reporting the signal.
2759 This avoids recursion while collecting (when a signal arrives
2760 midway, and the signal handler itself collects), which would trash
2761 the trace buffer. In case the user set a breakpoint in a signal
2762 handler, this avoids the backtrace showing the jump pad, etc..
2763 Most importantly, there are certain things we can't do safely if
2764 threads are stopped in a jump pad (or in its callee's). For
2767 - starting a new trace run. A thread still collecting the
2768 previous run, could trash the trace buffer when resumed. The trace
2769 buffer control structures would have been reset but the thread had
2770 no way to tell. The thread could even midway memcpy'ing to the
2771 buffer, which would mean that when resumed, it would clobber the
2772 trace buffer that had been set for a new run.
2774 - we can't rewrite/reuse the jump pads for new tracepoints
2775 safely. Say you do tstart while a thread is stopped midway while
2776 collecting. When the thread is later resumed, it finishes the
2777 collection, and returns to the jump pad, to execute the original
2778 instruction that was under the tracepoint jump at the time the
2779 older run had been started. If the jump pad had been rewritten
2780 since for something else in the new run, the thread would now
2781 execute the wrong / random instructions. */
2784 linux_process_target::stabilize_threads ()
2786 thread_info
*thread_stuck
= find_thread ([this] (thread_info
*thread
)
2788 return stuck_in_jump_pad (thread
);
2791 if (thread_stuck
!= NULL
)
2793 threads_debug_printf ("can't stabilize, LWP %ld is stuck in jump pad",
2794 lwpid_of (thread_stuck
));
2798 scoped_restore_current_thread restore_thread
;
2800 stabilizing_threads
= 1;
2803 for_each_thread ([this] (thread_info
*thread
)
2805 move_out_of_jump_pad (thread
);
2808 /* Loop until all are stopped out of the jump pads. */
2809 while (find_thread (lwp_running
) != NULL
)
2811 struct target_waitstatus ourstatus
;
2812 struct lwp_info
*lwp
;
2815 /* Note that we go through the full wait even loop. While
2816 moving threads out of jump pad, we need to be able to step
2817 over internal breakpoints and such. */
2818 wait_1 (minus_one_ptid
, &ourstatus
, 0);
2820 if (ourstatus
.kind () == TARGET_WAITKIND_STOPPED
)
2822 lwp
= get_thread_lwp (current_thread
);
2825 lwp_suspended_inc (lwp
);
2827 if (ourstatus
.sig () != GDB_SIGNAL_0
2828 || current_thread
->last_resume_kind
== resume_stop
)
2830 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.sig ()));
2831 enqueue_one_deferred_signal (lwp
, &wstat
);
2836 unsuspend_all_lwps (NULL
);
2838 stabilizing_threads
= 0;
2842 thread_stuck
= find_thread ([this] (thread_info
*thread
)
2844 return stuck_in_jump_pad (thread
);
2847 if (thread_stuck
!= NULL
)
2848 threads_debug_printf
2849 ("couldn't stabilize, LWP %ld got stuck in jump pad",
2850 lwpid_of (thread_stuck
));
2854 /* Convenience function that is called when the kernel reports an
2855 event that is not passed out to GDB. */
2858 ignore_event (struct target_waitstatus
*ourstatus
)
2860 /* If we got an event, there may still be others, as a single
2861 SIGCHLD can indicate more than one child stopped. This forces
2862 another target_wait call. */
2865 ourstatus
->set_ignore ();
2870 linux_process_target::filter_exit_event (lwp_info
*event_child
,
2871 target_waitstatus
*ourstatus
)
2873 client_state
&cs
= get_client_state ();
2874 struct thread_info
*thread
= get_lwp_thread (event_child
);
2875 ptid_t ptid
= ptid_of (thread
);
2877 if (!is_leader (thread
))
2879 if (cs
.report_thread_events
)
2880 ourstatus
->set_thread_exited (0);
2882 ourstatus
->set_ignore ();
2884 delete_lwp (event_child
);
2889 /* Returns 1 if GDB is interested in any event_child syscalls. */
2892 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
2894 struct thread_info
*thread
= get_lwp_thread (event_child
);
2895 struct process_info
*proc
= get_thread_process (thread
);
2897 return !proc
->syscalls_to_catch
.empty ();
2901 linux_process_target::gdb_catch_this_syscall (lwp_info
*event_child
)
2904 struct thread_info
*thread
= get_lwp_thread (event_child
);
2905 struct process_info
*proc
= get_thread_process (thread
);
2907 if (proc
->syscalls_to_catch
.empty ())
2910 if (proc
->syscalls_to_catch
[0] == ANY_SYSCALL
)
2913 get_syscall_trapinfo (event_child
, &sysno
);
2915 for (int iter
: proc
->syscalls_to_catch
)
2923 linux_process_target::wait_1 (ptid_t ptid
, target_waitstatus
*ourstatus
,
2924 target_wait_flags target_options
)
2926 THREADS_SCOPED_DEBUG_ENTER_EXIT
;
2928 client_state
&cs
= get_client_state ();
2930 struct lwp_info
*event_child
;
2933 int step_over_finished
;
2934 int bp_explains_trap
;
2935 int maybe_internal_trap
;
2941 threads_debug_printf ("[%s]", target_pid_to_str (ptid
).c_str ());
2943 /* Translate generic target options into linux options. */
2945 if (target_options
& TARGET_WNOHANG
)
2948 bp_explains_trap
= 0;
2951 ourstatus
->set_ignore ();
2953 auto status_pending_p_any
= [&] (thread_info
*thread
)
2955 return status_pending_p_callback (thread
, minus_one_ptid
);
2958 auto not_stopped
= [&] (thread_info
*thread
)
2960 return not_stopped_callback (thread
, minus_one_ptid
);
2963 /* Find a resumed LWP, if any. */
2964 if (find_thread (status_pending_p_any
) != NULL
)
2966 else if (find_thread (not_stopped
) != NULL
)
2971 if (step_over_bkpt
== null_ptid
)
2972 pid
= wait_for_event (ptid
, &w
, options
);
2975 threads_debug_printf ("step_over_bkpt set [%s], doing a blocking wait",
2976 target_pid_to_str (step_over_bkpt
).c_str ());
2977 pid
= wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2980 if (pid
== 0 || (pid
== -1 && !any_resumed
))
2982 gdb_assert (target_options
& TARGET_WNOHANG
);
2984 threads_debug_printf ("ret = null_ptid, TARGET_WAITKIND_IGNORE");
2986 ourstatus
->set_ignore ();
2991 threads_debug_printf ("ret = null_ptid, TARGET_WAITKIND_NO_RESUMED");
2993 ourstatus
->set_no_resumed ();
2997 event_child
= get_thread_lwp (current_thread
);
2999 /* wait_for_event only returns an exit status for the last
3000 child of a process. Report it. */
3001 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3005 ourstatus
->set_exited (WEXITSTATUS (w
));
3007 threads_debug_printf
3008 ("ret = %s, exited with retcode %d",
3009 target_pid_to_str (ptid_of (current_thread
)).c_str (),
3014 ourstatus
->set_signalled (gdb_signal_from_host (WTERMSIG (w
)));
3016 threads_debug_printf
3017 ("ret = %s, terminated with signal %d",
3018 target_pid_to_str (ptid_of (current_thread
)).c_str (),
3022 if (ourstatus
->kind () == TARGET_WAITKIND_EXITED
)
3023 return filter_exit_event (event_child
, ourstatus
);
3025 return ptid_of (current_thread
);
3028 /* If step-over executes a breakpoint instruction, in the case of a
3029 hardware single step it means a gdb/gdbserver breakpoint had been
3030 planted on top of a permanent breakpoint, in the case of a software
3031 single step it may just mean that gdbserver hit the reinsert breakpoint.
3032 The PC has been adjusted by save_stop_reason to point at
3033 the breakpoint address.
3034 So in the case of the hardware single step advance the PC manually
3035 past the breakpoint and in the case of software single step advance only
3036 if it's not the single_step_breakpoint we are hitting.
3037 This avoids that a program would keep trapping a permanent breakpoint
3039 if (step_over_bkpt
!= null_ptid
3040 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3041 && (event_child
->stepping
3042 || !single_step_breakpoint_inserted_here (event_child
->stop_pc
)))
3044 int increment_pc
= 0;
3045 int breakpoint_kind
= 0;
3046 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3048 breakpoint_kind
= breakpoint_kind_from_current_state (&stop_pc
);
3049 sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3051 threads_debug_printf
3052 ("step-over for %s executed software breakpoint",
3053 target_pid_to_str (ptid_of (current_thread
)).c_str ());
3055 if (increment_pc
!= 0)
3057 struct regcache
*regcache
3058 = get_thread_regcache (current_thread
, 1);
3060 event_child
->stop_pc
+= increment_pc
;
3061 low_set_pc (regcache
, event_child
->stop_pc
);
3063 if (!low_breakpoint_at (event_child
->stop_pc
))
3064 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3068 /* If this event was not handled before, and is not a SIGTRAP, we
3069 report it. SIGILL and SIGSEGV are also treated as traps in case
3070 a breakpoint is inserted at the current PC. If this target does
3071 not support internal breakpoints at all, we also report the
3072 SIGTRAP without further processing; it's of no concern to us. */
3074 = (low_supports_breakpoints ()
3075 && (WSTOPSIG (w
) == SIGTRAP
3076 || ((WSTOPSIG (w
) == SIGILL
3077 || WSTOPSIG (w
) == SIGSEGV
)
3078 && low_breakpoint_at (event_child
->stop_pc
))));
3080 if (maybe_internal_trap
)
3082 /* Handle anything that requires bookkeeping before deciding to
3083 report the event or continue waiting. */
3085 /* First check if we can explain the SIGTRAP with an internal
3086 breakpoint, or if we should possibly report the event to GDB.
3087 Do this before anything that may remove or insert a
3089 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3091 /* We have a SIGTRAP, possibly a step-over dance has just
3092 finished. If so, tweak the state machine accordingly,
3093 reinsert breakpoints and delete any single-step
3095 step_over_finished
= finish_step_over (event_child
);
3097 /* Now invoke the callbacks of any internal breakpoints there. */
3098 check_breakpoints (event_child
->stop_pc
);
3100 /* Handle tracepoint data collecting. This may overflow the
3101 trace buffer, and cause a tracing stop, removing
3103 trace_event
= handle_tracepoints (event_child
);
3105 if (bp_explains_trap
)
3106 threads_debug_printf ("Hit a gdbserver breakpoint.");
3110 /* We have some other signal, possibly a step-over dance was in
3111 progress, and it should be cancelled too. */
3112 step_over_finished
= finish_step_over (event_child
);
3115 /* We have all the data we need. Either report the event to GDB, or
3116 resume threads and keep waiting for more. */
3118 /* If we're collecting a fast tracepoint, finish the collection and
3119 move out of the jump pad before delivering a signal. See
3120 linux_stabilize_threads. */
3123 && WSTOPSIG (w
) != SIGTRAP
3124 && supports_fast_tracepoints ()
3125 && agent_loaded_p ())
3127 threads_debug_printf ("Got signal %d for LWP %ld. Check if we need "
3128 "to defer or adjust it.",
3129 WSTOPSIG (w
), lwpid_of (current_thread
));
3131 /* Allow debugging the jump pad itself. */
3132 if (current_thread
->last_resume_kind
!= resume_step
3133 && maybe_move_out_of_jump_pad (event_child
, &w
))
3135 enqueue_one_deferred_signal (event_child
, &w
);
3137 threads_debug_printf ("Signal %d for LWP %ld deferred (in jump pad)",
3138 WSTOPSIG (w
), lwpid_of (current_thread
));
3140 resume_one_lwp (event_child
, 0, 0, NULL
);
3142 return ignore_event (ourstatus
);
3146 if (event_child
->collecting_fast_tracepoint
3147 != fast_tpoint_collect_result::not_collecting
)
3149 threads_debug_printf
3150 ("LWP %ld was trying to move out of the jump pad (%d). "
3151 "Check if we're already there.",
3152 lwpid_of (current_thread
),
3153 (int) event_child
->collecting_fast_tracepoint
);
3157 event_child
->collecting_fast_tracepoint
3158 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3160 if (event_child
->collecting_fast_tracepoint
3161 != fast_tpoint_collect_result::before_insn
)
3163 /* No longer need this breakpoint. */
3164 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3166 threads_debug_printf
3167 ("No longer need exit-jump-pad bkpt; removing it."
3168 "stopping all threads momentarily.");
3170 /* Other running threads could hit this breakpoint.
3171 We don't handle moribund locations like GDB does,
3172 instead we always pause all threads when removing
3173 breakpoints, so that any step-over or
3174 decr_pc_after_break adjustment is always taken
3175 care of while the breakpoint is still
3177 stop_all_lwps (1, event_child
);
3179 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3180 event_child
->exit_jump_pad_bkpt
= NULL
;
3182 unstop_all_lwps (1, event_child
);
3184 gdb_assert (event_child
->suspended
>= 0);
3188 if (event_child
->collecting_fast_tracepoint
3189 == fast_tpoint_collect_result::not_collecting
)
3191 threads_debug_printf
3192 ("fast tracepoint finished collecting successfully.");
3194 /* We may have a deferred signal to report. */
3195 if (dequeue_one_deferred_signal (event_child
, &w
))
3196 threads_debug_printf ("dequeued one signal.");
3199 threads_debug_printf ("no deferred signals.");
3201 if (stabilizing_threads
)
3203 ourstatus
->set_stopped (GDB_SIGNAL_0
);
3205 threads_debug_printf
3206 ("ret = %s, stopped while stabilizing threads",
3207 target_pid_to_str (ptid_of (current_thread
)).c_str ());
3209 return ptid_of (current_thread
);
3215 /* Check whether GDB would be interested in this event. */
3217 /* Check if GDB is interested in this syscall. */
3219 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3220 && !gdb_catch_this_syscall (event_child
))
3222 threads_debug_printf ("Ignored syscall for LWP %ld.",
3223 lwpid_of (current_thread
));
3225 resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
3227 return ignore_event (ourstatus
);
3230 /* If GDB is not interested in this signal, don't stop other
3231 threads, and don't report it to GDB. Just resume the inferior
3232 right away. We do this for threading-related signals as well as
3233 any that GDB specifically requested we ignore. But never ignore
3234 SIGSTOP if we sent it ourselves, and do not ignore signals when
3235 stepping - they may require special handling to skip the signal
3236 handler. Also never ignore signals that could be caused by a
3239 && current_thread
->last_resume_kind
!= resume_step
3241 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3242 (current_process ()->priv
->thread_db
!= NULL
3243 && (WSTOPSIG (w
) == __SIGRTMIN
3244 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3247 (cs
.pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3248 && !(WSTOPSIG (w
) == SIGSTOP
3249 && current_thread
->last_resume_kind
== resume_stop
)
3250 && !linux_wstatus_maybe_breakpoint (w
))))
3252 siginfo_t info
, *info_p
;
3254 threads_debug_printf ("Ignored signal %d for LWP %ld.",
3255 WSTOPSIG (w
), lwpid_of (current_thread
));
3257 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3258 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3263 if (step_over_finished
)
3265 /* We cancelled this thread's step-over above. We still
3266 need to unsuspend all other LWPs, and set them back
3267 running again while the signal handler runs. */
3268 unsuspend_all_lwps (event_child
);
3270 /* Enqueue the pending signal info so that proceed_all_lwps
3272 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3274 proceed_all_lwps ();
3278 resume_one_lwp (event_child
, event_child
->stepping
,
3279 WSTOPSIG (w
), info_p
);
3282 return ignore_event (ourstatus
);
3285 /* Note that all addresses are always "out of the step range" when
3286 there's no range to begin with. */
3287 in_step_range
= lwp_in_step_range (event_child
);
3289 /* If GDB wanted this thread to single step, and the thread is out
3290 of the step range, we always want to report the SIGTRAP, and let
3291 GDB handle it. Watchpoints should always be reported. So should
3292 signals we can't explain. A SIGTRAP we can't explain could be a
3293 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3294 do, we're be able to handle GDB breakpoints on top of internal
3295 breakpoints, by handling the internal breakpoint and still
3296 reporting the event to GDB. If we don't, we're out of luck, GDB
3297 won't see the breakpoint hit. If we see a single-step event but
3298 the thread should be continuing, don't pass the trap to gdb.
3299 That indicates that we had previously finished a single-step but
3300 left the single-step pending -- see
3301 complete_ongoing_step_over. */
3302 report_to_gdb
= (!maybe_internal_trap
3303 || (current_thread
->last_resume_kind
== resume_step
3305 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3307 && !bp_explains_trap
3309 && !step_over_finished
3310 && !(current_thread
->last_resume_kind
== resume_continue
3311 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3312 || (gdb_breakpoint_here (event_child
->stop_pc
)
3313 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3314 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3315 || event_child
->waitstatus
.kind () != TARGET_WAITKIND_IGNORE
);
3317 run_breakpoint_commands (event_child
->stop_pc
);
3319 /* We found no reason GDB would want us to stop. We either hit one
3320 of our own breakpoints, or finished an internal step GDB
3321 shouldn't know about. */
3324 if (bp_explains_trap
)
3325 threads_debug_printf ("Hit a gdbserver breakpoint.");
3327 if (step_over_finished
)
3328 threads_debug_printf ("Step-over finished.");
3331 threads_debug_printf ("Tracepoint event.");
3333 if (lwp_in_step_range (event_child
))
3334 threads_debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).",
3335 paddress (event_child
->stop_pc
),
3336 paddress (event_child
->step_range_start
),
3337 paddress (event_child
->step_range_end
));
3339 /* We're not reporting this breakpoint to GDB, so apply the
3340 decr_pc_after_break adjustment to the inferior's regcache
3343 if (low_supports_breakpoints ())
3345 struct regcache
*regcache
3346 = get_thread_regcache (current_thread
, 1);
3347 low_set_pc (regcache
, event_child
->stop_pc
);
3350 if (step_over_finished
)
3352 /* If we have finished stepping over a breakpoint, we've
3353 stopped and suspended all LWPs momentarily except the
3354 stepping one. This is where we resume them all again.
3355 We're going to keep waiting, so use proceed, which
3356 handles stepping over the next breakpoint. */
3357 unsuspend_all_lwps (event_child
);
3361 /* Remove the single-step breakpoints if any. Note that
3362 there isn't single-step breakpoint if we finished stepping
3364 if (supports_software_single_step ()
3365 && has_single_step_breakpoints (current_thread
))
3367 stop_all_lwps (0, event_child
);
3368 delete_single_step_breakpoints (current_thread
);
3369 unstop_all_lwps (0, event_child
);
3373 threads_debug_printf ("proceeding all threads.");
3375 proceed_all_lwps ();
3377 return ignore_event (ourstatus
);
3382 if (event_child
->waitstatus
.kind () != TARGET_WAITKIND_IGNORE
)
3383 threads_debug_printf ("LWP %ld: extended event with waitstatus %s",
3384 lwpid_of (get_lwp_thread (event_child
)),
3385 event_child
->waitstatus
.to_string ().c_str ());
3387 if (current_thread
->last_resume_kind
== resume_step
)
3389 if (event_child
->step_range_start
== event_child
->step_range_end
)
3390 threads_debug_printf
3391 ("GDB wanted to single-step, reporting event.");
3392 else if (!lwp_in_step_range (event_child
))
3393 threads_debug_printf ("Out of step range, reporting event.");
3396 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3397 threads_debug_printf ("Stopped by watchpoint.");
3398 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3399 threads_debug_printf ("Stopped by GDB breakpoint.");
3402 threads_debug_printf ("Hit a non-gdbserver trap event.");
3404 /* Alright, we're going to report a stop. */
3406 /* Remove single-step breakpoints. */
3407 if (supports_software_single_step ())
3409 /* Remove single-step breakpoints or not. It it is true, stop all
3410 lwps, so that other threads won't hit the breakpoint in the
3412 int remove_single_step_breakpoints_p
= 0;
3416 remove_single_step_breakpoints_p
3417 = has_single_step_breakpoints (current_thread
);
3421 /* In all-stop, a stop reply cancels all previous resume
3422 requests. Delete all single-step breakpoints. */
3424 find_thread ([&] (thread_info
*thread
) {
3425 if (has_single_step_breakpoints (thread
))
3427 remove_single_step_breakpoints_p
= 1;
3435 if (remove_single_step_breakpoints_p
)
3437 /* If we remove single-step breakpoints from memory, stop all lwps,
3438 so that other threads won't hit the breakpoint in the staled
3440 stop_all_lwps (0, event_child
);
3444 gdb_assert (has_single_step_breakpoints (current_thread
));
3445 delete_single_step_breakpoints (current_thread
);
3449 for_each_thread ([] (thread_info
*thread
){
3450 if (has_single_step_breakpoints (thread
))
3451 delete_single_step_breakpoints (thread
);
3455 unstop_all_lwps (0, event_child
);
3459 if (!stabilizing_threads
)
3461 /* In all-stop, stop all threads. */
3463 stop_all_lwps (0, NULL
);
3465 if (step_over_finished
)
3469 /* If we were doing a step-over, all other threads but
3470 the stepping one had been paused in start_step_over,
3471 with their suspend counts incremented. We don't want
3472 to do a full unstop/unpause, because we're in
3473 all-stop mode (so we want threads stopped), but we
3474 still need to unsuspend the other threads, to
3475 decrement their `suspended' count back. */
3476 unsuspend_all_lwps (event_child
);
3480 /* If we just finished a step-over, then all threads had
3481 been momentarily paused. In all-stop, that's fine,
3482 we want threads stopped by now anyway. In non-stop,
3483 we need to re-resume threads that GDB wanted to be
3485 unstop_all_lwps (1, event_child
);
3489 /* If we're not waiting for a specific LWP, choose an event LWP
3490 from among those that have had events. Giving equal priority
3491 to all LWPs that have had events helps prevent
3493 if (ptid
== minus_one_ptid
)
3495 event_child
->status_pending_p
= 1;
3496 event_child
->status_pending
= w
;
3498 select_event_lwp (&event_child
);
3500 /* current_thread and event_child must stay in sync. */
3501 switch_to_thread (get_lwp_thread (event_child
));
3503 event_child
->status_pending_p
= 0;
3504 w
= event_child
->status_pending
;
3508 /* Stabilize threads (move out of jump pads). */
3510 target_stabilize_threads ();
3514 /* If we just finished a step-over, then all threads had been
3515 momentarily paused. In all-stop, that's fine, we want
3516 threads stopped by now anyway. In non-stop, we need to
3517 re-resume threads that GDB wanted to be running. */
3518 if (step_over_finished
)
3519 unstop_all_lwps (1, event_child
);
3522 /* At this point, we haven't set OURSTATUS. This is where we do it. */
3523 gdb_assert (ourstatus
->kind () == TARGET_WAITKIND_IGNORE
);
3525 if (event_child
->waitstatus
.kind () != TARGET_WAITKIND_IGNORE
)
3527 /* If the reported event is an exit, fork, vfork or exec, let
3530 /* Break the unreported fork relationship chain. */
3531 if (event_child
->waitstatus
.kind () == TARGET_WAITKIND_FORKED
3532 || event_child
->waitstatus
.kind () == TARGET_WAITKIND_VFORKED
)
3534 event_child
->fork_relative
->fork_relative
= NULL
;
3535 event_child
->fork_relative
= NULL
;
3538 *ourstatus
= event_child
->waitstatus
;
3539 /* Clear the event lwp's waitstatus since we handled it already. */
3540 event_child
->waitstatus
.set_ignore ();
3544 /* The LWP stopped due to a plain signal or a syscall signal. Either way,
3545 event_chid->waitstatus wasn't filled in with the details, so look at
3546 the wait status W. */
3547 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3551 get_syscall_trapinfo (event_child
, &syscall_number
);
3552 if (event_child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
)
3553 ourstatus
->set_syscall_entry (syscall_number
);
3554 else if (event_child
->syscall_state
== TARGET_WAITKIND_SYSCALL_RETURN
)
3555 ourstatus
->set_syscall_return (syscall_number
);
3557 gdb_assert_not_reached ("unexpected syscall state");
3559 else if (current_thread
->last_resume_kind
== resume_stop
3560 && WSTOPSIG (w
) == SIGSTOP
)
3562 /* A thread that has been requested to stop by GDB with vCont;t,
3563 and it stopped cleanly, so report as SIG0. The use of
3564 SIGSTOP is an implementation detail. */
3565 ourstatus
->set_stopped (GDB_SIGNAL_0
);
3568 ourstatus
->set_stopped (gdb_signal_from_host (WSTOPSIG (w
)));
3571 /* Now that we've selected our final event LWP, un-adjust its PC if
3572 it was a software breakpoint, and the client doesn't know we can
3573 adjust the breakpoint ourselves. */
3574 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3575 && !cs
.swbreak_feature
)
3577 int decr_pc
= low_decr_pc_after_break ();
3581 struct regcache
*regcache
3582 = get_thread_regcache (current_thread
, 1);
3583 low_set_pc (regcache
, event_child
->stop_pc
+ decr_pc
);
3587 gdb_assert (step_over_bkpt
== null_ptid
);
3589 threads_debug_printf ("ret = %s, %s",
3590 target_pid_to_str (ptid_of (current_thread
)).c_str (),
3591 ourstatus
->to_string ().c_str ());
3593 if (ourstatus
->kind () == TARGET_WAITKIND_EXITED
)
3594 return filter_exit_event (event_child
, ourstatus
);
3596 return ptid_of (current_thread
);
3599 /* Get rid of any pending event in the pipe. */
3601 async_file_flush (void)
3603 linux_event_pipe
.flush ();
3606 /* Put something in the pipe, so the event loop wakes up. */
3608 async_file_mark (void)
3610 linux_event_pipe
.mark ();
3614 linux_process_target::wait (ptid_t ptid
,
3615 target_waitstatus
*ourstatus
,
3616 target_wait_flags target_options
)
3620 /* Flush the async file first. */
3621 if (target_is_async_p ())
3622 async_file_flush ();
3626 event_ptid
= wait_1 (ptid
, ourstatus
, target_options
);
3628 while ((target_options
& TARGET_WNOHANG
) == 0
3629 && event_ptid
== null_ptid
3630 && ourstatus
->kind () == TARGET_WAITKIND_IGNORE
);
3632 /* If at least one stop was reported, there may be more. A single
3633 SIGCHLD can signal more than one child stop. */
3634 if (target_is_async_p ()
3635 && (target_options
& TARGET_WNOHANG
) != 0
3636 && event_ptid
!= null_ptid
)
3642 /* Send a signal to an LWP. */
3645 kill_lwp (unsigned long lwpid
, int signo
)
3650 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3651 if (errno
== ENOSYS
)
3653 /* If tkill fails, then we are not using nptl threads, a
3654 configuration we no longer support. */
3655 perror_with_name (("tkill"));
3661 linux_stop_lwp (struct lwp_info
*lwp
)
3667 send_sigstop (struct lwp_info
*lwp
)
3671 pid
= lwpid_of (get_lwp_thread (lwp
));
3673 /* If we already have a pending stop signal for this process, don't
3675 if (lwp
->stop_expected
)
3677 threads_debug_printf ("Have pending sigstop for lwp %d", pid
);
3682 threads_debug_printf ("Sending sigstop to lwp %d", pid
);
3684 lwp
->stop_expected
= 1;
3685 kill_lwp (pid
, SIGSTOP
);
3689 send_sigstop (thread_info
*thread
, lwp_info
*except
)
3691 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3693 /* Ignore EXCEPT. */
3703 /* Increment the suspend count of an LWP, and stop it, if not stopped
3706 suspend_and_send_sigstop (thread_info
*thread
, lwp_info
*except
)
3708 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3710 /* Ignore EXCEPT. */
3714 lwp_suspended_inc (lwp
);
3716 send_sigstop (thread
, except
);
3720 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3722 /* Store the exit status for later. */
3723 lwp
->status_pending_p
= 1;
3724 lwp
->status_pending
= wstat
;
3726 /* Store in waitstatus as well, as there's nothing else to process
3728 if (WIFEXITED (wstat
))
3729 lwp
->waitstatus
.set_exited (WEXITSTATUS (wstat
));
3730 else if (WIFSIGNALED (wstat
))
3731 lwp
->waitstatus
.set_signalled (gdb_signal_from_host (WTERMSIG (wstat
)));
3733 /* Prevent trying to stop it. */
3736 /* No further stops are expected from a dead lwp. */
3737 lwp
->stop_expected
= 0;
3740 /* Return true if LWP has exited already, and has a pending exit event
3741 to report to GDB. */
3744 lwp_is_marked_dead (struct lwp_info
*lwp
)
3746 return (lwp
->status_pending_p
3747 && (WIFEXITED (lwp
->status_pending
)
3748 || WIFSIGNALED (lwp
->status_pending
)));
3752 linux_process_target::wait_for_sigstop ()
3754 struct thread_info
*saved_thread
;
3759 saved_thread
= current_thread
;
3760 if (saved_thread
!= NULL
)
3761 saved_tid
= saved_thread
->id
;
3763 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3765 scoped_restore_current_thread restore_thread
;
3767 threads_debug_printf ("pulling events");
3769 /* Passing NULL_PTID as filter indicates we want all events to be
3770 left pending. Eventually this returns when there are no
3771 unwaited-for children left. */
3772 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
, __WALL
);
3773 gdb_assert (ret
== -1);
3775 if (saved_thread
== NULL
|| mythread_alive (saved_tid
))
3779 threads_debug_printf ("Previously current thread died.");
3781 /* We can't change the current inferior behind GDB's back,
3782 otherwise, a subsequent command may apply to the wrong
3784 restore_thread
.dont_restore ();
3785 switch_to_thread (nullptr);
3790 linux_process_target::stuck_in_jump_pad (thread_info
*thread
)
3792 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3794 if (lwp
->suspended
!= 0)
3796 internal_error (__FILE__
, __LINE__
,
3797 "LWP %ld is suspended, suspended=%d\n",
3798 lwpid_of (thread
), lwp
->suspended
);
3800 gdb_assert (lwp
->stopped
);
3802 /* Allow debugging the jump pad, gdb_collect, etc.. */
3803 return (supports_fast_tracepoints ()
3804 && agent_loaded_p ()
3805 && (gdb_breakpoint_here (lwp
->stop_pc
)
3806 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3807 || thread
->last_resume_kind
== resume_step
)
3808 && (linux_fast_tracepoint_collecting (lwp
, NULL
)
3809 != fast_tpoint_collect_result::not_collecting
));
3813 linux_process_target::move_out_of_jump_pad (thread_info
*thread
)
3815 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3818 if (lwp
->suspended
!= 0)
3820 internal_error (__FILE__
, __LINE__
,
3821 "LWP %ld is suspended, suspended=%d\n",
3822 lwpid_of (thread
), lwp
->suspended
);
3824 gdb_assert (lwp
->stopped
);
3826 /* For gdb_breakpoint_here. */
3827 scoped_restore_current_thread restore_thread
;
3828 switch_to_thread (thread
);
3830 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3832 /* Allow debugging the jump pad, gdb_collect, etc. */
3833 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3834 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3835 && thread
->last_resume_kind
!= resume_step
3836 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3838 threads_debug_printf ("LWP %ld needs stabilizing (in jump pad)",
3843 lwp
->status_pending_p
= 0;
3844 enqueue_one_deferred_signal (lwp
, wstat
);
3846 threads_debug_printf ("Signal %d for LWP %ld deferred (in jump pad",
3847 WSTOPSIG (*wstat
), lwpid_of (thread
));
3850 resume_one_lwp (lwp
, 0, 0, NULL
);
3853 lwp_suspended_inc (lwp
);
3857 lwp_running (thread_info
*thread
)
3859 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3861 if (lwp_is_marked_dead (lwp
))
3864 return !lwp
->stopped
;
3868 linux_process_target::stop_all_lwps (int suspend
, lwp_info
*except
)
3870 /* Should not be called recursively. */
3871 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3873 THREADS_SCOPED_DEBUG_ENTER_EXIT
;
3875 threads_debug_printf
3876 ("%s, except=%s", suspend
? "stop-and-suspend" : "stop",
3878 ? target_pid_to_str (ptid_of (get_lwp_thread (except
))).c_str ()
3881 stopping_threads
= (suspend
3882 ? STOPPING_AND_SUSPENDING_THREADS
3883 : STOPPING_THREADS
);
3886 for_each_thread ([&] (thread_info
*thread
)
3888 suspend_and_send_sigstop (thread
, except
);
3891 for_each_thread ([&] (thread_info
*thread
)
3893 send_sigstop (thread
, except
);
3896 wait_for_sigstop ();
3897 stopping_threads
= NOT_STOPPING_THREADS
;
3899 threads_debug_printf ("setting stopping_threads back to !stopping");
3902 /* Enqueue one signal in the chain of signals which need to be
3903 delivered to this process on next resume. */
3906 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
3908 lwp
->pending_signals
.emplace_back (signal
);
3909 if (info
== nullptr)
3910 memset (&lwp
->pending_signals
.back ().info
, 0, sizeof (siginfo_t
));
3912 lwp
->pending_signals
.back ().info
= *info
;
3916 linux_process_target::install_software_single_step_breakpoints (lwp_info
*lwp
)
3918 struct thread_info
*thread
= get_lwp_thread (lwp
);
3919 struct regcache
*regcache
= get_thread_regcache (thread
, 1);
3921 scoped_restore_current_thread restore_thread
;
3923 switch_to_thread (thread
);
3924 std::vector
<CORE_ADDR
> next_pcs
= low_get_next_pcs (regcache
);
3926 for (CORE_ADDR pc
: next_pcs
)
3927 set_single_step_breakpoint (pc
, current_ptid
);
3931 linux_process_target::single_step (lwp_info
* lwp
)
3935 if (supports_hardware_single_step ())
3939 else if (supports_software_single_step ())
3941 install_software_single_step_breakpoints (lwp
);
3945 threads_debug_printf ("stepping is not implemented on this target");
3950 /* The signal can be delivered to the inferior if we are not trying to
3951 finish a fast tracepoint collect. Since signal can be delivered in
3952 the step-over, the program may go to signal handler and trap again
3953 after return from the signal handler. We can live with the spurious
3957 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
3959 return (lwp
->collecting_fast_tracepoint
3960 == fast_tpoint_collect_result::not_collecting
);
3964 linux_process_target::resume_one_lwp_throw (lwp_info
*lwp
, int step
,
3965 int signal
, siginfo_t
*info
)
3967 struct thread_info
*thread
= get_lwp_thread (lwp
);
3969 struct process_info
*proc
= get_thread_process (thread
);
3971 /* Note that target description may not be initialised
3972 (proc->tdesc == NULL) at this point because the program hasn't
3973 stopped at the first instruction yet. It means GDBserver skips
3974 the extra traps from the wrapper program (see option --wrapper).
3975 Code in this function that requires register access should be
3976 guarded by proc->tdesc == NULL or something else. */
3978 if (lwp
->stopped
== 0)
3981 gdb_assert (lwp
->waitstatus
.kind () == TARGET_WAITKIND_IGNORE
);
3983 fast_tpoint_collect_result fast_tp_collecting
3984 = lwp
->collecting_fast_tracepoint
;
3986 gdb_assert (!stabilizing_threads
3987 || (fast_tp_collecting
3988 != fast_tpoint_collect_result::not_collecting
));
3990 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3991 user used the "jump" command, or "set $pc = foo"). */
3992 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
3994 /* Collecting 'while-stepping' actions doesn't make sense
3996 release_while_stepping_state_list (thread
);
3999 /* If we have pending signals or status, and a new signal, enqueue the
4000 signal. Also enqueue the signal if it can't be delivered to the
4001 inferior right now. */
4003 && (lwp
->status_pending_p
4004 || !lwp
->pending_signals
.empty ()
4005 || !lwp_signal_can_be_delivered (lwp
)))
4007 enqueue_pending_signal (lwp
, signal
, info
);
4009 /* Postpone any pending signal. It was enqueued above. */
4013 if (lwp
->status_pending_p
)
4015 threads_debug_printf
4016 ("Not resuming lwp %ld (%s, stop %s); has pending status",
4017 lwpid_of (thread
), step
? "step" : "continue",
4018 lwp
->stop_expected
? "expected" : "not expected");
4022 scoped_restore_current_thread restore_thread
;
4023 switch_to_thread (thread
);
4025 /* This bit needs some thinking about. If we get a signal that
4026 we must report while a single-step reinsert is still pending,
4027 we often end up resuming the thread. It might be better to
4028 (ew) allow a stack of pending events; then we could be sure that
4029 the reinsert happened right away and not lose any signals.
4031 Making this stack would also shrink the window in which breakpoints are
4032 uninserted (see comment in linux_wait_for_lwp) but not enough for
4033 complete correctness, so it won't solve that problem. It may be
4034 worthwhile just to solve this one, however. */
4035 if (lwp
->bp_reinsert
!= 0)
4037 threads_debug_printf (" pending reinsert at 0x%s",
4038 paddress (lwp
->bp_reinsert
));
4040 if (supports_hardware_single_step ())
4042 if (fast_tp_collecting
== fast_tpoint_collect_result::not_collecting
)
4045 warning ("BAD - reinserting but not stepping.");
4047 warning ("BAD - reinserting and suspended(%d).",
4052 step
= maybe_hw_step (thread
);
4055 if (fast_tp_collecting
== fast_tpoint_collect_result::before_insn
)
4056 threads_debug_printf
4057 ("lwp %ld wants to get out of fast tracepoint jump pad "
4058 "(exit-jump-pad-bkpt)", lwpid_of (thread
));
4060 else if (fast_tp_collecting
== fast_tpoint_collect_result::at_insn
)
4062 threads_debug_printf
4063 ("lwp %ld wants to get out of fast tracepoint jump pad single-stepping",
4066 if (supports_hardware_single_step ())
4070 internal_error (__FILE__
, __LINE__
,
4071 "moving out of jump pad single-stepping"
4072 " not implemented on this target");
4076 /* If we have while-stepping actions in this thread set it stepping.
4077 If we have a signal to deliver, it may or may not be set to
4078 SIG_IGN, we don't know. Assume so, and allow collecting
4079 while-stepping into a signal handler. A possible smart thing to
4080 do would be to set an internal breakpoint at the signal return
4081 address, continue, and carry on catching this while-stepping
4082 action only when that breakpoint is hit. A future
4084 if (thread
->while_stepping
!= NULL
)
4086 threads_debug_printf
4087 ("lwp %ld has a while-stepping action -> forcing step.",
4090 step
= single_step (lwp
);
4093 if (proc
->tdesc
!= NULL
&& low_supports_breakpoints ())
4095 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4097 lwp
->stop_pc
= low_get_pc (regcache
);
4099 threads_debug_printf (" %s from pc 0x%lx", step
? "step" : "continue",
4100 (long) lwp
->stop_pc
);
4103 /* If we have pending signals, consume one if it can be delivered to
4105 if (!lwp
->pending_signals
.empty () && lwp_signal_can_be_delivered (lwp
))
4107 const pending_signal
&p_sig
= lwp
->pending_signals
.front ();
4109 signal
= p_sig
.signal
;
4110 if (p_sig
.info
.si_signo
!= 0)
4111 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4114 lwp
->pending_signals
.pop_front ();
4117 threads_debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)",
4118 lwpid_of (thread
), step
? "step" : "continue", signal
,
4119 lwp
->stop_expected
? "expected" : "not expected");
4121 low_prepare_to_resume (lwp
);
4123 regcache_invalidate_thread (thread
);
4125 lwp
->stepping
= step
;
4127 ptrace_request
= PTRACE_SINGLESTEP
;
4128 else if (gdb_catching_syscalls_p (lwp
))
4129 ptrace_request
= PTRACE_SYSCALL
;
4131 ptrace_request
= PTRACE_CONT
;
4132 ptrace (ptrace_request
,
4134 (PTRACE_TYPE_ARG3
) 0,
4135 /* Coerce to a uintptr_t first to avoid potential gcc warning
4136 of coercing an 8 byte integer to a 4 byte pointer. */
4137 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4141 int saved_errno
= errno
;
4143 threads_debug_printf ("ptrace errno = %d (%s)",
4144 saved_errno
, strerror (saved_errno
));
4146 errno
= saved_errno
;
4147 perror_with_name ("resuming thread");
4150 /* Successfully resumed. Clear state that no longer makes sense,
4151 and mark the LWP as running. Must not do this before resuming
4152 otherwise if that fails other code will be confused. E.g., we'd
4153 later try to stop the LWP and hang forever waiting for a stop
4154 status. Note that we must not throw after this is cleared,
4155 otherwise handle_zombie_lwp_error would get confused. */
4157 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4161 linux_process_target::low_prepare_to_resume (lwp_info
*lwp
)
4166 /* Called when we try to resume a stopped LWP and that errors out. If
4167 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4168 or about to become), discard the error, clear any pending status
4169 the LWP may have, and return true (we'll collect the exit status
4170 soon enough). Otherwise, return false. */
4173 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4175 struct thread_info
*thread
= get_lwp_thread (lp
);
4177 /* If we get an error after resuming the LWP successfully, we'd
4178 confuse !T state for the LWP being gone. */
4179 gdb_assert (lp
->stopped
);
4181 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4182 because even if ptrace failed with ESRCH, the tracee may be "not
4183 yet fully dead", but already refusing ptrace requests. In that
4184 case the tracee has 'R (Running)' state for a little bit
4185 (observed in Linux 3.18). See also the note on ESRCH in the
4186 ptrace(2) man page. Instead, check whether the LWP has any state
4187 other than ptrace-stopped. */
4189 /* Don't assume anything if /proc/PID/status can't be read. */
4190 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4192 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4193 lp
->status_pending_p
= 0;
4200 linux_process_target::resume_one_lwp (lwp_info
*lwp
, int step
, int signal
,
4205 resume_one_lwp_throw (lwp
, step
, signal
, info
);
4207 catch (const gdb_exception_error
&ex
)
4209 if (check_ptrace_stopped_lwp_gone (lwp
))
4211 /* This could because we tried to resume an LWP after its leader
4212 exited. Mark it as resumed, so we can collect an exit event
4215 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4222 /* This function is called once per thread via for_each_thread.
4223 We look up which resume request applies to THREAD and mark it with a
4224 pointer to the appropriate resume request.
4226 This algorithm is O(threads * resume elements), but resume elements
4227 is small (and will remain small at least until GDB supports thread
4231 linux_set_resume_request (thread_info
*thread
, thread_resume
*resume
, size_t n
)
4233 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4235 for (int ndx
= 0; ndx
< n
; ndx
++)
4237 ptid_t ptid
= resume
[ndx
].thread
;
4238 if (ptid
== minus_one_ptid
4239 || ptid
== thread
->id
4240 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4242 || (ptid
.pid () == pid_of (thread
)
4244 || ptid
.lwp () == -1)))
4246 if (resume
[ndx
].kind
== resume_stop
4247 && thread
->last_resume_kind
== resume_stop
)
4249 threads_debug_printf
4250 ("already %s LWP %ld at GDB's request",
4251 (thread
->last_status
.kind () == TARGET_WAITKIND_STOPPED
4252 ? "stopped" : "stopping"),
4258 /* Ignore (wildcard) resume requests for already-resumed
4260 if (resume
[ndx
].kind
!= resume_stop
4261 && thread
->last_resume_kind
!= resume_stop
)
4263 threads_debug_printf
4264 ("already %s LWP %ld at GDB's request",
4265 (thread
->last_resume_kind
== resume_step
4266 ? "stepping" : "continuing"),
4271 /* Don't let wildcard resumes resume fork children that GDB
4272 does not yet know are new fork children. */
4273 if (lwp
->fork_relative
!= NULL
)
4275 struct lwp_info
*rel
= lwp
->fork_relative
;
4277 if (rel
->status_pending_p
4278 && (rel
->waitstatus
.kind () == TARGET_WAITKIND_FORKED
4279 || rel
->waitstatus
.kind () == TARGET_WAITKIND_VFORKED
))
4281 threads_debug_printf
4282 ("not resuming LWP %ld: has queued stop reply",
4288 /* If the thread has a pending event that has already been
4289 reported to GDBserver core, but GDB has not pulled the
4290 event out of the vStopped queue yet, likewise, ignore the
4291 (wildcard) resume request. */
4292 if (in_queued_stop_replies (thread
->id
))
4294 threads_debug_printf
4295 ("not resuming LWP %ld: has queued stop reply",
4300 lwp
->resume
= &resume
[ndx
];
4301 thread
->last_resume_kind
= lwp
->resume
->kind
;
4303 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4304 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4306 /* If we had a deferred signal to report, dequeue one now.
4307 This can happen if LWP gets more than one signal while
4308 trying to get out of a jump pad. */
4310 && !lwp
->status_pending_p
4311 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4313 lwp
->status_pending_p
= 1;
4315 threads_debug_printf
4316 ("Dequeueing deferred signal %d for LWP %ld, "
4317 "leaving status pending.",
4318 WSTOPSIG (lwp
->status_pending
),
4326 /* No resume action for this thread. */
4331 linux_process_target::resume_status_pending (thread_info
*thread
)
4333 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4335 /* LWPs which will not be resumed are not interesting, because
4336 we might not wait for them next time through linux_wait. */
4337 if (lwp
->resume
== NULL
)
4340 return thread_still_has_status_pending (thread
);
4344 linux_process_target::thread_needs_step_over (thread_info
*thread
)
4346 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4348 struct process_info
*proc
= get_thread_process (thread
);
4350 /* GDBserver is skipping the extra traps from the wrapper program,
4351 don't have to do step over. */
4352 if (proc
->tdesc
== NULL
)
4355 /* LWPs which will not be resumed are not interesting, because we
4356 might not wait for them next time through linux_wait. */
4360 threads_debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped",
4365 if (thread
->last_resume_kind
== resume_stop
)
4367 threads_debug_printf
4368 ("Need step over [LWP %ld]? Ignoring, should remain stopped",
4373 gdb_assert (lwp
->suspended
>= 0);
4377 threads_debug_printf ("Need step over [LWP %ld]? Ignoring, suspended",
4382 if (lwp
->status_pending_p
)
4384 threads_debug_printf
4385 ("Need step over [LWP %ld]? Ignoring, has pending status.",
4390 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4394 /* If the PC has changed since we stopped, then don't do anything,
4395 and let the breakpoint/tracepoint be hit. This happens if, for
4396 instance, GDB handled the decr_pc_after_break subtraction itself,
4397 GDB is OOL stepping this thread, or the user has issued a "jump"
4398 command, or poked thread's registers herself. */
4399 if (pc
!= lwp
->stop_pc
)
4401 threads_debug_printf
4402 ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4403 "Old stop_pc was 0x%s, PC is now 0x%s", lwpid_of (thread
),
4404 paddress (lwp
->stop_pc
), paddress (pc
));
4408 /* On software single step target, resume the inferior with signal
4409 rather than stepping over. */
4410 if (supports_software_single_step ()
4411 && !lwp
->pending_signals
.empty ()
4412 && lwp_signal_can_be_delivered (lwp
))
4414 threads_debug_printf
4415 ("Need step over [LWP %ld]? Ignoring, has pending signals.",
4421 scoped_restore_current_thread restore_thread
;
4422 switch_to_thread (thread
);
4424 /* We can only step over breakpoints we know about. */
4425 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4427 /* Don't step over a breakpoint that GDB expects to hit
4428 though. If the condition is being evaluated on the target's side
4429 and it evaluate to false, step over this breakpoint as well. */
4430 if (gdb_breakpoint_here (pc
)
4431 && gdb_condition_true_at_breakpoint (pc
)
4432 && gdb_no_commands_at_breakpoint (pc
))
4434 threads_debug_printf ("Need step over [LWP %ld]? yes, but found"
4435 " GDB breakpoint at 0x%s; skipping step over",
4436 lwpid_of (thread
), paddress (pc
));
4442 threads_debug_printf ("Need step over [LWP %ld]? yes, "
4443 "found breakpoint at 0x%s",
4444 lwpid_of (thread
), paddress (pc
));
4446 /* We've found an lwp that needs stepping over --- return 1 so
4447 that find_thread stops looking. */
4452 threads_debug_printf
4453 ("Need step over [LWP %ld]? No, no breakpoint found at 0x%s",
4454 lwpid_of (thread
), paddress (pc
));
4460 linux_process_target::start_step_over (lwp_info
*lwp
)
4462 struct thread_info
*thread
= get_lwp_thread (lwp
);
4465 threads_debug_printf ("Starting step-over on LWP %ld. Stopping all threads",
4468 stop_all_lwps (1, lwp
);
4470 if (lwp
->suspended
!= 0)
4472 internal_error (__FILE__
, __LINE__
,
4473 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4477 threads_debug_printf ("Done stopping all threads for step-over.");
4479 /* Note, we should always reach here with an already adjusted PC,
4480 either by GDB (if we're resuming due to GDB's request), or by our
4481 caller, if we just finished handling an internal breakpoint GDB
4482 shouldn't care about. */
4487 scoped_restore_current_thread restore_thread
;
4488 switch_to_thread (thread
);
4490 lwp
->bp_reinsert
= pc
;
4491 uninsert_breakpoints_at (pc
);
4492 uninsert_fast_tracepoint_jumps_at (pc
);
4494 step
= single_step (lwp
);
4497 resume_one_lwp (lwp
, step
, 0, NULL
);
4499 /* Require next event from this LWP. */
4500 step_over_bkpt
= thread
->id
;
4504 linux_process_target::finish_step_over (lwp_info
*lwp
)
4506 if (lwp
->bp_reinsert
!= 0)
4508 scoped_restore_current_thread restore_thread
;
4510 threads_debug_printf ("Finished step over.");
4512 switch_to_thread (get_lwp_thread (lwp
));
4514 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4515 may be no breakpoint to reinsert there by now. */
4516 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4517 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4519 lwp
->bp_reinsert
= 0;
4521 /* Delete any single-step breakpoints. No longer needed. We
4522 don't have to worry about other threads hitting this trap,
4523 and later not being able to explain it, because we were
4524 stepping over a breakpoint, and we hold all threads but
4525 LWP stopped while doing that. */
4526 if (!supports_hardware_single_step ())
4528 gdb_assert (has_single_step_breakpoints (current_thread
));
4529 delete_single_step_breakpoints (current_thread
);
4532 step_over_bkpt
= null_ptid
;
4540 linux_process_target::complete_ongoing_step_over ()
4542 if (step_over_bkpt
!= null_ptid
)
4544 struct lwp_info
*lwp
;
4548 threads_debug_printf ("detach: step over in progress, finish it first");
4550 /* Passing NULL_PTID as filter indicates we want all events to
4551 be left pending. Eventually this returns when there are no
4552 unwaited-for children left. */
4553 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
,
4555 gdb_assert (ret
== -1);
4557 lwp
= find_lwp_pid (step_over_bkpt
);
4560 finish_step_over (lwp
);
4562 /* If we got our step SIGTRAP, don't leave it pending,
4563 otherwise we would report it to GDB as a spurious
4565 gdb_assert (lwp
->status_pending_p
);
4566 if (WIFSTOPPED (lwp
->status_pending
)
4567 && WSTOPSIG (lwp
->status_pending
) == SIGTRAP
)
4569 thread_info
*thread
= get_lwp_thread (lwp
);
4570 if (thread
->last_resume_kind
!= resume_step
)
4572 threads_debug_printf ("detach: discard step-over SIGTRAP");
4574 lwp
->status_pending_p
= 0;
4575 lwp
->status_pending
= 0;
4576 resume_one_lwp (lwp
, lwp
->stepping
, 0, NULL
);
4579 threads_debug_printf
4580 ("detach: resume_step, not discarding step-over SIGTRAP");
4583 step_over_bkpt
= null_ptid
;
4584 unsuspend_all_lwps (lwp
);
4589 linux_process_target::resume_one_thread (thread_info
*thread
,
4590 bool leave_all_stopped
)
4592 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4595 if (lwp
->resume
== NULL
)
4598 if (lwp
->resume
->kind
== resume_stop
)
4600 threads_debug_printf ("resume_stop request for LWP %ld",
4605 threads_debug_printf ("stopping LWP %ld", lwpid_of (thread
));
4607 /* Stop the thread, and wait for the event asynchronously,
4608 through the event loop. */
4613 threads_debug_printf ("already stopped LWP %ld", lwpid_of (thread
));
4615 /* The LWP may have been stopped in an internal event that
4616 was not meant to be notified back to GDB (e.g., gdbserver
4617 breakpoint), so we should be reporting a stop event in
4620 /* If the thread already has a pending SIGSTOP, this is a
4621 no-op. Otherwise, something later will presumably resume
4622 the thread and this will cause it to cancel any pending
4623 operation, due to last_resume_kind == resume_stop. If
4624 the thread already has a pending status to report, we
4625 will still report it the next time we wait - see
4626 status_pending_p_callback. */
4628 /* If we already have a pending signal to report, then
4629 there's no need to queue a SIGSTOP, as this means we're
4630 midway through moving the LWP out of the jumppad, and we
4631 will report the pending signal as soon as that is
4633 if (lwp
->pending_signals_to_report
.empty ())
4637 /* For stop requests, we're done. */
4639 thread
->last_status
.set_ignore ();
4643 /* If this thread which is about to be resumed has a pending status,
4644 then don't resume it - we can just report the pending status.
4645 Likewise if it is suspended, because e.g., another thread is
4646 stepping past a breakpoint. Make sure to queue any signals that
4647 would otherwise be sent. In all-stop mode, we do this decision
4648 based on if *any* thread has a pending status. If there's a
4649 thread that needs the step-over-breakpoint dance, then don't
4650 resume any other thread but that particular one. */
4651 leave_pending
= (lwp
->suspended
4652 || lwp
->status_pending_p
4653 || leave_all_stopped
);
4655 /* If we have a new signal, enqueue the signal. */
4656 if (lwp
->resume
->sig
!= 0)
4658 siginfo_t info
, *info_p
;
4660 /* If this is the same signal we were previously stopped by,
4661 make sure to queue its siginfo. */
4662 if (WIFSTOPPED (lwp
->last_status
)
4663 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
4664 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
),
4665 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
4670 enqueue_pending_signal (lwp
, lwp
->resume
->sig
, info_p
);
4675 threads_debug_printf ("resuming LWP %ld", lwpid_of (thread
));
4677 proceed_one_lwp (thread
, NULL
);
4680 threads_debug_printf ("leaving LWP %ld stopped", lwpid_of (thread
));
4682 thread
->last_status
.set_ignore ();
4687 linux_process_target::resume (thread_resume
*resume_info
, size_t n
)
4689 struct thread_info
*need_step_over
= NULL
;
4691 THREADS_SCOPED_DEBUG_ENTER_EXIT
;
4693 for_each_thread ([&] (thread_info
*thread
)
4695 linux_set_resume_request (thread
, resume_info
, n
);
4698 /* If there is a thread which would otherwise be resumed, which has
4699 a pending status, then don't resume any threads - we can just
4700 report the pending status. Make sure to queue any signals that
4701 would otherwise be sent. In non-stop mode, we'll apply this
4702 logic to each thread individually. We consume all pending events
4703 before considering to start a step-over (in all-stop). */
4704 bool any_pending
= false;
4706 any_pending
= find_thread ([this] (thread_info
*thread
)
4708 return resume_status_pending (thread
);
4711 /* If there is a thread which would otherwise be resumed, which is
4712 stopped at a breakpoint that needs stepping over, then don't
4713 resume any threads - have it step over the breakpoint with all
4714 other threads stopped, then resume all threads again. Make sure
4715 to queue any signals that would otherwise be delivered or
4717 if (!any_pending
&& low_supports_breakpoints ())
4718 need_step_over
= find_thread ([this] (thread_info
*thread
)
4720 return thread_needs_step_over (thread
);
4723 bool leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4725 if (need_step_over
!= NULL
)
4726 threads_debug_printf ("Not resuming all, need step over");
4727 else if (any_pending
)
4728 threads_debug_printf ("Not resuming, all-stop and found "
4729 "an LWP with pending status");
4731 threads_debug_printf ("Resuming, no pending status or step over needed");
4733 /* Even if we're leaving threads stopped, queue all signals we'd
4734 otherwise deliver. */
4735 for_each_thread ([&] (thread_info
*thread
)
4737 resume_one_thread (thread
, leave_all_stopped
);
4741 start_step_over (get_thread_lwp (need_step_over
));
4743 /* We may have events that were pending that can/should be sent to
4744 the client now. Trigger a linux_wait call. */
4745 if (target_is_async_p ())
4750 linux_process_target::proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
4752 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4758 threads_debug_printf ("lwp %ld", lwpid_of (thread
));
4762 threads_debug_printf (" LWP %ld already running", lwpid_of (thread
));
4766 if (thread
->last_resume_kind
== resume_stop
4767 && thread
->last_status
.kind () != TARGET_WAITKIND_IGNORE
)
4769 threads_debug_printf (" client wants LWP to remain %ld stopped",
4774 if (lwp
->status_pending_p
)
4776 threads_debug_printf (" LWP %ld has pending status, leaving stopped",
4781 gdb_assert (lwp
->suspended
>= 0);
4785 threads_debug_printf (" LWP %ld is suspended", lwpid_of (thread
));
4789 if (thread
->last_resume_kind
== resume_stop
4790 && lwp
->pending_signals_to_report
.empty ()
4791 && (lwp
->collecting_fast_tracepoint
4792 == fast_tpoint_collect_result::not_collecting
))
4794 /* We haven't reported this LWP as stopped yet (otherwise, the
4795 last_status.kind check above would catch it, and we wouldn't
4796 reach here. This LWP may have been momentarily paused by a
4797 stop_all_lwps call while handling for example, another LWP's
4798 step-over. In that case, the pending expected SIGSTOP signal
4799 that was queued at vCont;t handling time will have already
4800 been consumed by wait_for_sigstop, and so we need to requeue
4801 another one here. Note that if the LWP already has a SIGSTOP
4802 pending, this is a no-op. */
4804 threads_debug_printf
4805 ("Client wants LWP %ld to stop. Making sure it has a SIGSTOP pending",
4811 if (thread
->last_resume_kind
== resume_step
)
4813 threads_debug_printf (" stepping LWP %ld, client wants it stepping",
4816 /* If resume_step is requested by GDB, install single-step
4817 breakpoints when the thread is about to be actually resumed if
4818 the single-step breakpoints weren't removed. */
4819 if (supports_software_single_step ()
4820 && !has_single_step_breakpoints (thread
))
4821 install_software_single_step_breakpoints (lwp
);
4823 step
= maybe_hw_step (thread
);
4825 else if (lwp
->bp_reinsert
!= 0)
4827 threads_debug_printf (" stepping LWP %ld, reinsert set",
4830 step
= maybe_hw_step (thread
);
4835 resume_one_lwp (lwp
, step
, 0, NULL
);
4839 linux_process_target::unsuspend_and_proceed_one_lwp (thread_info
*thread
,
4842 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4847 lwp_suspended_decr (lwp
);
4849 proceed_one_lwp (thread
, except
);
4853 linux_process_target::proceed_all_lwps ()
4855 struct thread_info
*need_step_over
;
4857 /* If there is a thread which would otherwise be resumed, which is
4858 stopped at a breakpoint that needs stepping over, then don't
4859 resume any threads - have it step over the breakpoint with all
4860 other threads stopped, then resume all threads again. */
4862 if (low_supports_breakpoints ())
4864 need_step_over
= find_thread ([this] (thread_info
*thread
)
4866 return thread_needs_step_over (thread
);
4869 if (need_step_over
!= NULL
)
4871 threads_debug_printf ("found thread %ld needing a step-over",
4872 lwpid_of (need_step_over
));
4874 start_step_over (get_thread_lwp (need_step_over
));
4879 threads_debug_printf ("Proceeding, no step-over needed");
4881 for_each_thread ([this] (thread_info
*thread
)
4883 proceed_one_lwp (thread
, NULL
);
4888 linux_process_target::unstop_all_lwps (int unsuspend
, lwp_info
*except
)
4890 THREADS_SCOPED_DEBUG_ENTER_EXIT
;
4893 threads_debug_printf ("except=(LWP %ld)",
4894 lwpid_of (get_lwp_thread (except
)));
4896 threads_debug_printf ("except=nullptr");
4899 for_each_thread ([&] (thread_info
*thread
)
4901 unsuspend_and_proceed_one_lwp (thread
, except
);
4904 for_each_thread ([&] (thread_info
*thread
)
4906 proceed_one_lwp (thread
, except
);
4911 #ifdef HAVE_LINUX_REGSETS
4913 #define use_linux_regsets 1
4915 /* Returns true if REGSET has been disabled. */
4918 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
4920 return (info
->disabled_regsets
!= NULL
4921 && info
->disabled_regsets
[regset
- info
->regsets
]);
4924 /* Disable REGSET. */
4927 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
4931 dr_offset
= regset
- info
->regsets
;
4932 if (info
->disabled_regsets
== NULL
)
4933 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
4934 info
->disabled_regsets
[dr_offset
] = 1;
4938 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
4939 struct regcache
*regcache
)
4941 struct regset_info
*regset
;
4942 int saw_general_regs
= 0;
4946 pid
= lwpid_of (current_thread
);
4947 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4952 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4955 buf
= xmalloc (regset
->size
);
4957 nt_type
= regset
->nt_type
;
4961 iov
.iov_len
= regset
->size
;
4962 data
= (void *) &iov
;
4968 res
= ptrace (regset
->get_request
, pid
,
4969 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4971 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4976 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
4978 /* If we get EIO on a regset, or an EINVAL and the regset is
4979 optional, do not try it again for this process mode. */
4980 disable_regset (regsets_info
, regset
);
4982 else if (errno
== ENODATA
)
4984 /* ENODATA may be returned if the regset is currently
4985 not "active". This can happen in normal operation,
4986 so suppress the warning in this case. */
4988 else if (errno
== ESRCH
)
4990 /* At this point, ESRCH should mean the process is
4991 already gone, in which case we simply ignore attempts
4992 to read its registers. */
4997 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5004 if (regset
->type
== GENERAL_REGS
)
5005 saw_general_regs
= 1;
5006 regset
->store_function (regcache
, buf
);
5010 if (saw_general_regs
)
5017 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5018 struct regcache
*regcache
)
5020 struct regset_info
*regset
;
5021 int saw_general_regs
= 0;
5025 pid
= lwpid_of (current_thread
);
5026 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5031 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5032 || regset
->fill_function
== NULL
)
5035 buf
= xmalloc (regset
->size
);
5037 /* First fill the buffer with the current register set contents,
5038 in case there are any items in the kernel's regset that are
5039 not in gdbserver's regcache. */
5041 nt_type
= regset
->nt_type
;
5045 iov
.iov_len
= regset
->size
;
5046 data
= (void *) &iov
;
5052 res
= ptrace (regset
->get_request
, pid
,
5053 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5055 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5060 /* Then overlay our cached registers on that. */
5061 regset
->fill_function (regcache
, buf
);
5063 /* Only now do we write the register set. */
5065 res
= ptrace (regset
->set_request
, pid
,
5066 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5068 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5075 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
5077 /* If we get EIO on a regset, or an EINVAL and the regset is
5078 optional, do not try it again for this process mode. */
5079 disable_regset (regsets_info
, regset
);
5081 else if (errno
== ESRCH
)
5083 /* At this point, ESRCH should mean the process is
5084 already gone, in which case we simply ignore attempts
5085 to change its registers. See also the related
5086 comment in resume_one_lwp. */
5092 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5095 else if (regset
->type
== GENERAL_REGS
)
5096 saw_general_regs
= 1;
5099 if (saw_general_regs
)
5105 #else /* !HAVE_LINUX_REGSETS */
5107 #define use_linux_regsets 0
5108 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5109 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5113 /* Return 1 if register REGNO is supported by one of the regset ptrace
5114 calls or 0 if it has to be transferred individually. */
5117 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5119 unsigned char mask
= 1 << (regno
% 8);
5120 size_t index
= regno
/ 8;
5122 return (use_linux_regsets
5123 && (regs_info
->regset_bitmap
== NULL
5124 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5127 #ifdef HAVE_LINUX_USRREGS
5130 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5134 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5135 error ("Invalid register number %d.", regnum
);
5137 addr
= usrregs
->regmap
[regnum
];
5144 linux_process_target::fetch_register (const usrregs_info
*usrregs
,
5145 regcache
*regcache
, int regno
)
5152 if (regno
>= usrregs
->num_regs
)
5154 if (low_cannot_fetch_register (regno
))
5157 regaddr
= register_addr (usrregs
, regno
);
5161 size
= ((register_size (regcache
->tdesc
, regno
)
5162 + sizeof (PTRACE_XFER_TYPE
) - 1)
5163 & -sizeof (PTRACE_XFER_TYPE
));
5164 buf
= (char *) alloca (size
);
5166 pid
= lwpid_of (current_thread
);
5167 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5170 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5171 ptrace (PTRACE_PEEKUSER
, pid
,
5172 /* Coerce to a uintptr_t first to avoid potential gcc warning
5173 of coercing an 8 byte integer to a 4 byte pointer. */
5174 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5175 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5178 /* Mark register REGNO unavailable. */
5179 supply_register (regcache
, regno
, NULL
);
5184 low_supply_ptrace_register (regcache
, regno
, buf
);
5188 linux_process_target::store_register (const usrregs_info
*usrregs
,
5189 regcache
*regcache
, int regno
)
5196 if (regno
>= usrregs
->num_regs
)
5198 if (low_cannot_store_register (regno
))
5201 regaddr
= register_addr (usrregs
, regno
);
5205 size
= ((register_size (regcache
->tdesc
, regno
)
5206 + sizeof (PTRACE_XFER_TYPE
) - 1)
5207 & -sizeof (PTRACE_XFER_TYPE
));
5208 buf
= (char *) alloca (size
);
5209 memset (buf
, 0, size
);
5211 low_collect_ptrace_register (regcache
, regno
, buf
);
5213 pid
= lwpid_of (current_thread
);
5214 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5217 ptrace (PTRACE_POKEUSER
, pid
,
5218 /* Coerce to a uintptr_t first to avoid potential gcc warning
5219 about coercing an 8 byte integer to a 4 byte pointer. */
5220 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5221 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5224 /* At this point, ESRCH should mean the process is
5225 already gone, in which case we simply ignore attempts
5226 to change its registers. See also the related
5227 comment in resume_one_lwp. */
5232 if (!low_cannot_store_register (regno
))
5233 error ("writing register %d: %s", regno
, safe_strerror (errno
));
5235 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5238 #endif /* HAVE_LINUX_USRREGS */
5241 linux_process_target::low_collect_ptrace_register (regcache
*regcache
,
5242 int regno
, char *buf
)
5244 collect_register (regcache
, regno
, buf
);
5248 linux_process_target::low_supply_ptrace_register (regcache
*regcache
,
5249 int regno
, const char *buf
)
5251 supply_register (regcache
, regno
, buf
);
5255 linux_process_target::usr_fetch_inferior_registers (const regs_info
*regs_info
,
5259 #ifdef HAVE_LINUX_USRREGS
5260 struct usrregs_info
*usr
= regs_info
->usrregs
;
5264 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5265 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5266 fetch_register (usr
, regcache
, regno
);
5269 fetch_register (usr
, regcache
, regno
);
5274 linux_process_target::usr_store_inferior_registers (const regs_info
*regs_info
,
5278 #ifdef HAVE_LINUX_USRREGS
5279 struct usrregs_info
*usr
= regs_info
->usrregs
;
5283 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5284 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5285 store_register (usr
, regcache
, regno
);
5288 store_register (usr
, regcache
, regno
);
5293 linux_process_target::fetch_registers (regcache
*regcache
, int regno
)
5297 const regs_info
*regs_info
= get_regs_info ();
5301 if (regs_info
->usrregs
!= NULL
)
5302 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5303 low_fetch_register (regcache
, regno
);
5305 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5306 if (regs_info
->usrregs
!= NULL
)
5307 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5311 if (low_fetch_register (regcache
, regno
))
5314 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5316 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5318 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5319 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5324 linux_process_target::store_registers (regcache
*regcache
, int regno
)
5328 const regs_info
*regs_info
= get_regs_info ();
5332 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5334 if (regs_info
->usrregs
!= NULL
)
5335 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5339 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5341 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5343 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5344 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5349 linux_process_target::low_fetch_register (regcache
*regcache
, int regno
)
5354 /* A wrapper for the read_memory target op. */
5357 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5359 return the_target
->read_memory (memaddr
, myaddr
, len
);
5363 /* Helper for read_memory/write_memory using /proc/PID/mem. Because
5364 we can use a single read/write call, this can be much more
5365 efficient than banging away at PTRACE_PEEKTEXT. Also, unlike
5366 PTRACE_PEEKTEXT/PTRACE_POKETEXT, this works with running threads.
5367 One an only one of READBUF and WRITEBUF is non-null. If READBUF is
5368 not null, then we're reading, otherwise we're writing. */
5371 proc_xfer_memory (CORE_ADDR memaddr
, unsigned char *readbuf
,
5372 const gdb_byte
*writebuf
, int len
)
5374 gdb_assert ((readbuf
== nullptr) != (writebuf
== nullptr));
5376 process_info
*proc
= current_process ();
5378 int fd
= proc
->priv
->mem_fd
;
5386 /* If pread64 is available, use it. It's faster if the kernel
5387 supports it (only one syscall), and it's 64-bit safe even on
5388 32-bit platforms (for instance, SPARC debugging a SPARC64
5391 bytes
= (readbuf
!= nullptr
5392 ? pread64 (fd
, readbuf
, len
, memaddr
)
5393 : pwrite64 (fd
, writebuf
, len
, memaddr
));
5396 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5397 bytes
= (readbuf
!= nullptr
5398 ? read (fd
, readbuf
, len
)
5399 ? write (fd
, writebuf
, len
));
5404 else if (bytes
== 0)
5406 /* EOF means the address space is gone, the whole process
5407 exited or execed. */
5412 if (readbuf
!= nullptr)
5423 linux_process_target::read_memory (CORE_ADDR memaddr
,
5424 unsigned char *myaddr
, int len
)
5426 return proc_xfer_memory (memaddr
, myaddr
, nullptr, len
);
5429 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5430 memory at MEMADDR. On failure (cannot write to the inferior)
5431 returns the value of errno. Always succeeds if LEN is zero. */
5434 linux_process_target::write_memory (CORE_ADDR memaddr
,
5435 const unsigned char *myaddr
, int len
)
5439 /* Dump up to four bytes. */
5440 char str
[4 * 2 + 1];
5442 int dump
= len
< 4 ? len
: 4;
5444 for (int i
= 0; i
< dump
; i
++)
5446 sprintf (p
, "%02x", myaddr
[i
]);
5451 threads_debug_printf ("Writing %s to 0x%08lx in process %d",
5452 str
, (long) memaddr
, current_process ()->pid
);
5455 return proc_xfer_memory (memaddr
, nullptr, myaddr
, len
);
5459 linux_process_target::look_up_symbols ()
5461 #ifdef USE_THREAD_DB
5462 struct process_info
*proc
= current_process ();
5464 if (proc
->priv
->thread_db
!= NULL
)
5472 linux_process_target::request_interrupt ()
5474 /* Send a SIGINT to the process group. This acts just like the user
5475 typed a ^C on the controlling terminal. */
5476 ::kill (-signal_pid
, SIGINT
);
5480 linux_process_target::supports_read_auxv ()
5485 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5486 to debugger memory starting at MYADDR. */
5489 linux_process_target::read_auxv (CORE_ADDR offset
, unsigned char *myaddr
,
5492 char filename
[PATH_MAX
];
5494 int pid
= lwpid_of (current_thread
);
5496 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5498 fd
= open (filename
, O_RDONLY
);
5502 if (offset
!= (CORE_ADDR
) 0
5503 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5506 n
= read (fd
, myaddr
, len
);
5514 linux_process_target::insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5515 int size
, raw_breakpoint
*bp
)
5517 if (type
== raw_bkpt_type_sw
)
5518 return insert_memory_breakpoint (bp
);
5520 return low_insert_point (type
, addr
, size
, bp
);
5524 linux_process_target::low_insert_point (raw_bkpt_type type
, CORE_ADDR addr
,
5525 int size
, raw_breakpoint
*bp
)
5527 /* Unsupported (see target.h). */
5532 linux_process_target::remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5533 int size
, raw_breakpoint
*bp
)
5535 if (type
== raw_bkpt_type_sw
)
5536 return remove_memory_breakpoint (bp
);
5538 return low_remove_point (type
, addr
, size
, bp
);
5542 linux_process_target::low_remove_point (raw_bkpt_type type
, CORE_ADDR addr
,
5543 int size
, raw_breakpoint
*bp
)
5545 /* Unsupported (see target.h). */
5549 /* Implement the stopped_by_sw_breakpoint target_ops
5553 linux_process_target::stopped_by_sw_breakpoint ()
5555 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5557 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5560 /* Implement the supports_stopped_by_sw_breakpoint target_ops
5564 linux_process_target::supports_stopped_by_sw_breakpoint ()
5566 return USE_SIGTRAP_SIGINFO
;
5569 /* Implement the stopped_by_hw_breakpoint target_ops
5573 linux_process_target::stopped_by_hw_breakpoint ()
5575 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5577 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5580 /* Implement the supports_stopped_by_hw_breakpoint target_ops
5584 linux_process_target::supports_stopped_by_hw_breakpoint ()
5586 return USE_SIGTRAP_SIGINFO
;
5589 /* Implement the supports_hardware_single_step target_ops method. */
5592 linux_process_target::supports_hardware_single_step ()
5598 linux_process_target::stopped_by_watchpoint ()
5600 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5602 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5606 linux_process_target::stopped_data_address ()
5608 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5610 return lwp
->stopped_data_address
;
5613 /* This is only used for targets that define PT_TEXT_ADDR,
5614 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5615 the target has different ways of acquiring this information, like
5619 linux_process_target::supports_read_offsets ()
5621 #ifdef SUPPORTS_READ_OFFSETS
5628 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5629 to tell gdb about. */
5632 linux_process_target::read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5634 #ifdef SUPPORTS_READ_OFFSETS
5635 unsigned long text
, text_end
, data
;
5636 int pid
= lwpid_of (current_thread
);
5640 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5641 (PTRACE_TYPE_ARG4
) 0);
5642 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5643 (PTRACE_TYPE_ARG4
) 0);
5644 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5645 (PTRACE_TYPE_ARG4
) 0);
5649 /* Both text and data offsets produced at compile-time (and so
5650 used by gdb) are relative to the beginning of the program,
5651 with the data segment immediately following the text segment.
5652 However, the actual runtime layout in memory may put the data
5653 somewhere else, so when we send gdb a data base-address, we
5654 use the real data base address and subtract the compile-time
5655 data base-address from it (which is just the length of the
5656 text segment). BSS immediately follows data in both
5659 *data_p
= data
- (text_end
- text
);
5665 gdb_assert_not_reached ("target op read_offsets not supported");
5670 linux_process_target::supports_get_tls_address ()
5672 #ifdef USE_THREAD_DB
5680 linux_process_target::get_tls_address (thread_info
*thread
,
5682 CORE_ADDR load_module
,
5685 #ifdef USE_THREAD_DB
5686 return thread_db_get_tls_address (thread
, offset
, load_module
, address
);
5693 linux_process_target::supports_qxfer_osdata ()
5699 linux_process_target::qxfer_osdata (const char *annex
,
5700 unsigned char *readbuf
,
5701 unsigned const char *writebuf
,
5702 CORE_ADDR offset
, int len
)
5704 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5708 linux_process_target::siginfo_fixup (siginfo_t
*siginfo
,
5709 gdb_byte
*inf_siginfo
, int direction
)
5711 bool done
= low_siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5713 /* If there was no callback, or the callback didn't do anything,
5714 then just do a straight memcpy. */
5718 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5720 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5725 linux_process_target::low_siginfo_fixup (siginfo_t
*native
, gdb_byte
*inf
,
5732 linux_process_target::supports_qxfer_siginfo ()
5738 linux_process_target::qxfer_siginfo (const char *annex
,
5739 unsigned char *readbuf
,
5740 unsigned const char *writebuf
,
5741 CORE_ADDR offset
, int len
)
5745 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
5747 if (current_thread
== NULL
)
5750 pid
= lwpid_of (current_thread
);
5752 threads_debug_printf ("%s siginfo for lwp %d.",
5753 readbuf
!= NULL
? "Reading" : "Writing",
5756 if (offset
>= sizeof (siginfo
))
5759 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5762 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5763 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5764 inferior with a 64-bit GDBSERVER should look the same as debugging it
5765 with a 32-bit GDBSERVER, we need to convert it. */
5766 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
5768 if (offset
+ len
> sizeof (siginfo
))
5769 len
= sizeof (siginfo
) - offset
;
5771 if (readbuf
!= NULL
)
5772 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
5775 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
5777 /* Convert back to ptrace layout before flushing it out. */
5778 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
5780 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5787 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5788 so we notice when children change state; as the handler for the
5789 sigsuspend in my_waitpid. */
5792 sigchld_handler (int signo
)
5794 int old_errno
= errno
;
5800 /* Use the async signal safe debug function. */
5801 if (debug_write ("sigchld_handler\n",
5802 sizeof ("sigchld_handler\n") - 1) < 0)
5803 break; /* just ignore */
5807 if (target_is_async_p ())
5808 async_file_mark (); /* trigger a linux_wait */
5814 linux_process_target::supports_non_stop ()
5820 linux_process_target::async (bool enable
)
5822 bool previous
= target_is_async_p ();
5824 threads_debug_printf ("async (%d), previous=%d",
5827 if (previous
!= enable
)
5830 sigemptyset (&mask
);
5831 sigaddset (&mask
, SIGCHLD
);
5833 gdb_sigmask (SIG_BLOCK
, &mask
, NULL
);
5837 if (!linux_event_pipe
.open_pipe ())
5839 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
5841 warning ("creating event pipe failed.");
5845 /* Register the event loop handler. */
5846 add_file_handler (linux_event_pipe
.event_fd (),
5847 handle_target_event
, NULL
,
5850 /* Always trigger a linux_wait. */
5855 delete_file_handler (linux_event_pipe
.event_fd ());
5857 linux_event_pipe
.close_pipe ();
5860 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
5867 linux_process_target::start_non_stop (bool nonstop
)
5869 /* Register or unregister from event-loop accordingly. */
5870 target_async (nonstop
);
5872 if (target_is_async_p () != (nonstop
!= false))
5879 linux_process_target::supports_multi_process ()
5884 /* Check if fork events are supported. */
5887 linux_process_target::supports_fork_events ()
5892 /* Check if vfork events are supported. */
5895 linux_process_target::supports_vfork_events ()
5900 /* Check if exec events are supported. */
5903 linux_process_target::supports_exec_events ()
5908 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
5909 ptrace flags for all inferiors. This is in case the new GDB connection
5910 doesn't support the same set of events that the previous one did. */
5913 linux_process_target::handle_new_gdb_connection ()
5915 /* Request that all the lwps reset their ptrace options. */
5916 for_each_thread ([] (thread_info
*thread
)
5918 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5922 /* Stop the lwp so we can modify its ptrace options. */
5923 lwp
->must_set_ptrace_flags
= 1;
5924 linux_stop_lwp (lwp
);
5928 /* Already stopped; go ahead and set the ptrace options. */
5929 struct process_info
*proc
= find_process_pid (pid_of (thread
));
5930 int options
= linux_low_ptrace_options (proc
->attached
);
5932 linux_enable_event_reporting (lwpid_of (thread
), options
);
5933 lwp
->must_set_ptrace_flags
= 0;
5939 linux_process_target::handle_monitor_command (char *mon
)
5941 #ifdef USE_THREAD_DB
5942 return thread_db_handle_monitor_command (mon
);
5949 linux_process_target::core_of_thread (ptid_t ptid
)
5951 return linux_common_core_of_thread (ptid
);
5955 linux_process_target::supports_disable_randomization ()
5961 linux_process_target::supports_agent ()
5967 linux_process_target::supports_range_stepping ()
5969 if (supports_software_single_step ())
5972 return low_supports_range_stepping ();
5976 linux_process_target::low_supports_range_stepping ()
5982 linux_process_target::supports_pid_to_exec_file ()
5988 linux_process_target::pid_to_exec_file (int pid
)
5990 return linux_proc_pid_to_exec_file (pid
);
5994 linux_process_target::supports_multifs ()
6000 linux_process_target::multifs_open (int pid
, const char *filename
,
6001 int flags
, mode_t mode
)
6003 return linux_mntns_open_cloexec (pid
, filename
, flags
, mode
);
6007 linux_process_target::multifs_unlink (int pid
, const char *filename
)
6009 return linux_mntns_unlink (pid
, filename
);
6013 linux_process_target::multifs_readlink (int pid
, const char *filename
,
6014 char *buf
, size_t bufsiz
)
6016 return linux_mntns_readlink (pid
, filename
, buf
, bufsiz
);
6019 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6020 struct target_loadseg
6022 /* Core address to which the segment is mapped. */
6024 /* VMA recorded in the program header. */
6026 /* Size of this segment in memory. */
6030 # if defined PT_GETDSBT
6031 struct target_loadmap
6033 /* Protocol version number, must be zero. */
6035 /* Pointer to the DSBT table, its size, and the DSBT index. */
6036 unsigned *dsbt_table
;
6037 unsigned dsbt_size
, dsbt_index
;
6038 /* Number of segments in this map. */
6040 /* The actual memory map. */
6041 struct target_loadseg segs
[/*nsegs*/];
6043 # define LINUX_LOADMAP PT_GETDSBT
6044 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6045 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6047 struct target_loadmap
6049 /* Protocol version number, must be zero. */
6051 /* Number of segments in this map. */
6053 /* The actual memory map. */
6054 struct target_loadseg segs
[/*nsegs*/];
6056 # define LINUX_LOADMAP PTRACE_GETFDPIC
6057 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6058 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6062 linux_process_target::supports_read_loadmap ()
6068 linux_process_target::read_loadmap (const char *annex
, CORE_ADDR offset
,
6069 unsigned char *myaddr
, unsigned int len
)
6071 int pid
= lwpid_of (current_thread
);
6073 struct target_loadmap
*data
= NULL
;
6074 unsigned int actual_length
, copy_length
;
6076 if (strcmp (annex
, "exec") == 0)
6077 addr
= (int) LINUX_LOADMAP_EXEC
;
6078 else if (strcmp (annex
, "interp") == 0)
6079 addr
= (int) LINUX_LOADMAP_INTERP
;
6083 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6089 actual_length
= sizeof (struct target_loadmap
)
6090 + sizeof (struct target_loadseg
) * data
->nsegs
;
6092 if (offset
< 0 || offset
> actual_length
)
6095 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6096 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6099 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6102 linux_process_target::supports_catch_syscall ()
6104 return low_supports_catch_syscall ();
6108 linux_process_target::low_supports_catch_syscall ()
6114 linux_process_target::read_pc (regcache
*regcache
)
6116 if (!low_supports_breakpoints ())
6119 return low_get_pc (regcache
);
6123 linux_process_target::write_pc (regcache
*regcache
, CORE_ADDR pc
)
6125 gdb_assert (low_supports_breakpoints ());
6127 low_set_pc (regcache
, pc
);
6131 linux_process_target::supports_thread_stopped ()
6137 linux_process_target::thread_stopped (thread_info
*thread
)
6139 return get_thread_lwp (thread
)->stopped
;
6142 /* This exposes stop-all-threads functionality to other modules. */
6145 linux_process_target::pause_all (bool freeze
)
6147 stop_all_lwps (freeze
, NULL
);
6150 /* This exposes unstop-all-threads functionality to other gdbserver
6154 linux_process_target::unpause_all (bool unfreeze
)
6156 unstop_all_lwps (unfreeze
, NULL
);
6159 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6162 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6163 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6165 char filename
[PATH_MAX
];
6167 const int auxv_size
= is_elf64
6168 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6169 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6171 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6173 fd
= open (filename
, O_RDONLY
);
6179 while (read (fd
, buf
, auxv_size
) == auxv_size
6180 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6184 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6186 switch (aux
->a_type
)
6189 *phdr_memaddr
= aux
->a_un
.a_val
;
6192 *num_phdr
= aux
->a_un
.a_val
;
6198 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6200 switch (aux
->a_type
)
6203 *phdr_memaddr
= aux
->a_un
.a_val
;
6206 *num_phdr
= aux
->a_un
.a_val
;
6214 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6216 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6217 "phdr_memaddr = %ld, phdr_num = %d",
6218 (long) *phdr_memaddr
, *num_phdr
);
6225 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6228 get_dynamic (const int pid
, const int is_elf64
)
6230 CORE_ADDR phdr_memaddr
, relocation
;
6232 unsigned char *phdr_buf
;
6233 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6235 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6238 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6239 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6241 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6244 /* Compute relocation: it is expected to be 0 for "regular" executables,
6245 non-zero for PIE ones. */
6247 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6250 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6252 if (p
->p_type
== PT_PHDR
)
6253 relocation
= phdr_memaddr
- p
->p_vaddr
;
6257 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6259 if (p
->p_type
== PT_PHDR
)
6260 relocation
= phdr_memaddr
- p
->p_vaddr
;
6263 if (relocation
== -1)
6265 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6266 any real world executables, including PIE executables, have always
6267 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6268 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6269 or present DT_DEBUG anyway (fpc binaries are statically linked).
6271 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6273 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6278 for (i
= 0; i
< num_phdr
; i
++)
6282 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6284 if (p
->p_type
== PT_DYNAMIC
)
6285 return p
->p_vaddr
+ relocation
;
6289 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6291 if (p
->p_type
== PT_DYNAMIC
)
6292 return p
->p_vaddr
+ relocation
;
6299 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6300 can be 0 if the inferior does not yet have the library list initialized.
6301 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6302 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6305 get_r_debug (const int pid
, const int is_elf64
)
6307 CORE_ADDR dynamic_memaddr
;
6308 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6309 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6312 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6313 if (dynamic_memaddr
== 0)
6316 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6320 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6321 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6325 unsigned char buf
[sizeof (Elf64_Xword
)];
6329 #ifdef DT_MIPS_RLD_MAP
6330 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6332 if (linux_read_memory (dyn
->d_un
.d_val
,
6333 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6338 #endif /* DT_MIPS_RLD_MAP */
6339 #ifdef DT_MIPS_RLD_MAP_REL
6340 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6342 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6343 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6348 #endif /* DT_MIPS_RLD_MAP_REL */
6350 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6351 map
= dyn
->d_un
.d_val
;
6353 if (dyn
->d_tag
== DT_NULL
)
6358 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6359 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6363 unsigned char buf
[sizeof (Elf32_Word
)];
6367 #ifdef DT_MIPS_RLD_MAP
6368 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6370 if (linux_read_memory (dyn
->d_un
.d_val
,
6371 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6376 #endif /* DT_MIPS_RLD_MAP */
6377 #ifdef DT_MIPS_RLD_MAP_REL
6378 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6380 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6381 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6386 #endif /* DT_MIPS_RLD_MAP_REL */
6388 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6389 map
= dyn
->d_un
.d_val
;
6391 if (dyn
->d_tag
== DT_NULL
)
6395 dynamic_memaddr
+= dyn_size
;
6401 /* Read one pointer from MEMADDR in the inferior. */
6404 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6408 /* Go through a union so this works on either big or little endian
6409 hosts, when the inferior's pointer size is smaller than the size
6410 of CORE_ADDR. It is assumed the inferior's endianness is the
6411 same of the superior's. */
6414 CORE_ADDR core_addr
;
6419 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6422 if (ptr_size
== sizeof (CORE_ADDR
))
6423 *ptr
= addr
.core_addr
;
6424 else if (ptr_size
== sizeof (unsigned int))
6427 gdb_assert_not_reached ("unhandled pointer size");
6433 linux_process_target::supports_qxfer_libraries_svr4 ()
6438 struct link_map_offsets
6440 /* Offset and size of r_debug.r_version. */
6441 int r_version_offset
;
6443 /* Offset and size of r_debug.r_map. */
6446 /* Offset of r_debug_extended.r_next. */
6449 /* Offset to l_addr field in struct link_map. */
6452 /* Offset to l_name field in struct link_map. */
6455 /* Offset to l_ld field in struct link_map. */
6458 /* Offset to l_next field in struct link_map. */
6461 /* Offset to l_prev field in struct link_map. */
6465 static const link_map_offsets lmo_32bit_offsets
=
6467 0, /* r_version offset. */
6468 4, /* r_debug.r_map offset. */
6469 20, /* r_debug_extended.r_next. */
6470 0, /* l_addr offset in link_map. */
6471 4, /* l_name offset in link_map. */
6472 8, /* l_ld offset in link_map. */
6473 12, /* l_next offset in link_map. */
6474 16 /* l_prev offset in link_map. */
6477 static const link_map_offsets lmo_64bit_offsets
=
6479 0, /* r_version offset. */
6480 8, /* r_debug.r_map offset. */
6481 40, /* r_debug_extended.r_next. */
6482 0, /* l_addr offset in link_map. */
6483 8, /* l_name offset in link_map. */
6484 16, /* l_ld offset in link_map. */
6485 24, /* l_next offset in link_map. */
6486 32 /* l_prev offset in link_map. */
6489 /* Get the loaded shared libraries from one namespace. */
6492 read_link_map (std::string
&document
, CORE_ADDR lm_addr
, CORE_ADDR lm_prev
,
6493 int ptr_size
, const link_map_offsets
*lmo
, bool ignore_first
,
6496 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6499 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6500 &l_name
, ptr_size
) == 0
6501 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6502 &l_addr
, ptr_size
) == 0
6503 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6504 &l_ld
, ptr_size
) == 0
6505 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6506 &l_prev
, ptr_size
) == 0
6507 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6508 &l_next
, ptr_size
) == 0)
6510 unsigned char libname
[PATH_MAX
];
6512 if (lm_prev
!= l_prev
)
6514 warning ("Corrupted shared library list: 0x%s != 0x%s",
6515 paddress (lm_prev
), paddress (l_prev
));
6519 /* Ignore the first entry even if it has valid name as the first entry
6520 corresponds to the main executable. The first entry should not be
6521 skipped if the dynamic loader was loaded late by a static executable
6522 (see solib-svr4.c parameter ignore_first). But in such case the main
6523 executable does not have PT_DYNAMIC present and this function already
6524 exited above due to failed get_r_debug. */
6525 if (ignore_first
&& lm_prev
== 0)
6526 string_appendf (document
, " main-lm=\"0x%s\"", paddress (lm_addr
));
6529 /* Not checking for error because reading may stop before
6530 we've got PATH_MAX worth of characters. */
6532 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6533 libname
[sizeof (libname
) - 1] = '\0';
6534 if (libname
[0] != '\0')
6538 /* Terminate `<library-list-svr4'. */
6543 string_appendf (document
, "<library name=\"");
6544 xml_escape_text_append (&document
, (char *) libname
);
6545 string_appendf (document
, "\" lm=\"0x%s\" l_addr=\"0x%s\" "
6547 paddress (lm_addr
), paddress (l_addr
),
6557 /* Construct qXfer:libraries-svr4:read reply. */
6560 linux_process_target::qxfer_libraries_svr4 (const char *annex
,
6561 unsigned char *readbuf
,
6562 unsigned const char *writebuf
,
6563 CORE_ADDR offset
, int len
)
6565 struct process_info_private
*const priv
= current_process ()->priv
;
6566 char filename
[PATH_MAX
];
6568 unsigned int machine
;
6569 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6570 int header_done
= 0;
6572 if (writebuf
!= NULL
)
6574 if (readbuf
== NULL
)
6577 pid
= lwpid_of (current_thread
);
6578 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6579 is_elf64
= elf_64_file_p (filename
, &machine
);
6580 const link_map_offsets
*lmo
;
6584 lmo
= &lmo_64bit_offsets
;
6589 lmo
= &lmo_32bit_offsets
;
6593 while (annex
[0] != '\0')
6599 sep
= strchr (annex
, '=');
6603 name_len
= sep
- annex
;
6604 if (name_len
== 5 && startswith (annex
, "start"))
6606 else if (name_len
== 4 && startswith (annex
, "prev"))
6610 annex
= strchr (sep
, ';');
6617 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6620 std::string document
= "<library-list-svr4 version=\"1.0\"";
6622 /* When the starting LM_ADDR is passed in the annex, only traverse that
6625 Otherwise, start with R_DEBUG and traverse all namespaces we find. */
6627 read_link_map (document
, lm_addr
, lm_prev
, ptr_size
, lmo
, false,
6632 warning ("ignoring prev=0x%s without start", paddress (lm_prev
));
6634 CORE_ADDR r_debug
= priv
->r_debug
;
6636 r_debug
= priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6638 /* We failed to find DT_DEBUG. Such situation will not change
6639 for this inferior - do not retry it. Report it to GDB as
6640 E01, see for the reasons at the GDB solib-svr4.c side. */
6641 if (r_debug
== (CORE_ADDR
) -1)
6644 bool ignore_first
= true;
6645 while (r_debug
!= 0)
6648 if (linux_read_memory (r_debug
+ lmo
->r_version_offset
,
6649 (unsigned char *) &r_version
,
6650 sizeof (r_version
)) != 0)
6652 warning ("unable to read r_version from 0x%s",
6653 paddress (r_debug
+ lmo
->r_version_offset
));
6659 warning ("unexpected r_debug version %d", r_version
);
6663 if (read_one_ptr (r_debug
+ lmo
->r_map_offset
, &lm_addr
,
6666 warning ("unable to read r_map from 0x%s",
6667 paddress (r_debug
+ lmo
->r_map_offset
));
6671 read_link_map (document
, lm_addr
, 0, ptr_size
, lmo
,
6672 ignore_first
, header_done
);
6677 /* Only applies to the default namespace. */
6678 ignore_first
= false;
6680 if (read_one_ptr (r_debug
+ lmo
->r_next_offset
, &r_debug
,
6683 warning ("unable to read r_next from 0x%s",
6684 paddress (r_debug
+ lmo
->r_next_offset
));
6692 /* Empty list; terminate `<library-list-svr4'. */
6696 document
+= "</library-list-svr4>";
6698 int document_len
= document
.length ();
6699 if (offset
< document_len
)
6700 document_len
-= offset
;
6703 if (len
> document_len
)
6706 memcpy (readbuf
, document
.data () + offset
, len
);
6711 #ifdef HAVE_LINUX_BTRACE
6713 btrace_target_info
*
6714 linux_process_target::enable_btrace (thread_info
*tp
,
6715 const btrace_config
*conf
)
6717 return linux_enable_btrace (tp
->id
, conf
);
6720 /* See to_disable_btrace target method. */
6723 linux_process_target::disable_btrace (btrace_target_info
*tinfo
)
6725 enum btrace_error err
;
6727 err
= linux_disable_btrace (tinfo
);
6728 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6731 /* Encode an Intel Processor Trace configuration. */
6734 linux_low_encode_pt_config (struct buffer
*buffer
,
6735 const struct btrace_data_pt_config
*config
)
6737 buffer_grow_str (buffer
, "<pt-config>\n");
6739 switch (config
->cpu
.vendor
)
6742 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
6743 "model=\"%u\" stepping=\"%u\"/>\n",
6744 config
->cpu
.family
, config
->cpu
.model
,
6745 config
->cpu
.stepping
);
6752 buffer_grow_str (buffer
, "</pt-config>\n");
6755 /* Encode a raw buffer. */
6758 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
6764 /* We use hex encoding - see gdbsupport/rsp-low.h. */
6765 buffer_grow_str (buffer
, "<raw>\n");
6771 elem
[0] = tohex ((*data
>> 4) & 0xf);
6772 elem
[1] = tohex (*data
++ & 0xf);
6774 buffer_grow (buffer
, elem
, 2);
6777 buffer_grow_str (buffer
, "</raw>\n");
6780 /* See to_read_btrace target method. */
6783 linux_process_target::read_btrace (btrace_target_info
*tinfo
,
6785 enum btrace_read_type type
)
6787 struct btrace_data btrace
;
6788 enum btrace_error err
;
6790 err
= linux_read_btrace (&btrace
, tinfo
, type
);
6791 if (err
!= BTRACE_ERR_NONE
)
6793 if (err
== BTRACE_ERR_OVERFLOW
)
6794 buffer_grow_str0 (buffer
, "E.Overflow.");
6796 buffer_grow_str0 (buffer
, "E.Generic Error.");
6801 switch (btrace
.format
)
6803 case BTRACE_FORMAT_NONE
:
6804 buffer_grow_str0 (buffer
, "E.No Trace.");
6807 case BTRACE_FORMAT_BTS
:
6808 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6809 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6811 for (const btrace_block
&block
: *btrace
.variant
.bts
.blocks
)
6812 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
6813 paddress (block
.begin
), paddress (block
.end
));
6815 buffer_grow_str0 (buffer
, "</btrace>\n");
6818 case BTRACE_FORMAT_PT
:
6819 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6820 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6821 buffer_grow_str (buffer
, "<pt>\n");
6823 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
6825 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
6826 btrace
.variant
.pt
.size
);
6828 buffer_grow_str (buffer
, "</pt>\n");
6829 buffer_grow_str0 (buffer
, "</btrace>\n");
6833 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
6840 /* See to_btrace_conf target method. */
6843 linux_process_target::read_btrace_conf (const btrace_target_info
*tinfo
,
6846 const struct btrace_config
*conf
;
6848 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
6849 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
6851 conf
= linux_btrace_conf (tinfo
);
6854 switch (conf
->format
)
6856 case BTRACE_FORMAT_NONE
:
6859 case BTRACE_FORMAT_BTS
:
6860 buffer_xml_printf (buffer
, "<bts");
6861 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
6862 buffer_xml_printf (buffer
, " />\n");
6865 case BTRACE_FORMAT_PT
:
6866 buffer_xml_printf (buffer
, "<pt");
6867 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
6868 buffer_xml_printf (buffer
, "/>\n");
6873 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
6876 #endif /* HAVE_LINUX_BTRACE */
6878 /* See nat/linux-nat.h. */
6881 current_lwp_ptid (void)
6883 return ptid_of (current_thread
);
6887 linux_process_target::thread_name (ptid_t thread
)
6889 return linux_proc_tid_get_name (thread
);
6894 linux_process_target::thread_handle (ptid_t ptid
, gdb_byte
**handle
,
6897 return thread_db_thread_handle (ptid
, handle
, handle_len
);
6902 linux_process_target::thread_pending_parent (thread_info
*thread
)
6904 lwp_info
*parent
= get_thread_lwp (thread
)->pending_parent ();
6906 if (parent
== nullptr)
6909 return get_lwp_thread (parent
);
6913 linux_process_target::thread_pending_child (thread_info
*thread
)
6915 lwp_info
*child
= get_thread_lwp (thread
)->pending_child ();
6917 if (child
== nullptr)
6920 return get_lwp_thread (child
);
6923 /* Default implementation of linux_target_ops method "set_pc" for
6924 32-bit pc register which is literally named "pc". */
6927 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
6929 uint32_t newpc
= pc
;
6931 supply_register_by_name (regcache
, "pc", &newpc
);
6934 /* Default implementation of linux_target_ops method "get_pc" for
6935 32-bit pc register which is literally named "pc". */
6938 linux_get_pc_32bit (struct regcache
*regcache
)
6942 collect_register_by_name (regcache
, "pc", &pc
);
6943 threads_debug_printf ("stop pc is 0x%" PRIx32
, pc
);
6947 /* Default implementation of linux_target_ops method "set_pc" for
6948 64-bit pc register which is literally named "pc". */
6951 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
6953 uint64_t newpc
= pc
;
6955 supply_register_by_name (regcache
, "pc", &newpc
);
6958 /* Default implementation of linux_target_ops method "get_pc" for
6959 64-bit pc register which is literally named "pc". */
6962 linux_get_pc_64bit (struct regcache
*regcache
)
6966 collect_register_by_name (regcache
, "pc", &pc
);
6967 threads_debug_printf ("stop pc is 0x%" PRIx64
, pc
);
6971 /* See linux-low.h. */
6974 linux_get_auxv (int wordsize
, CORE_ADDR match
, CORE_ADDR
*valp
)
6976 gdb_byte
*data
= (gdb_byte
*) alloca (2 * wordsize
);
6979 gdb_assert (wordsize
== 4 || wordsize
== 8);
6981 while (the_target
->read_auxv (offset
, data
, 2 * wordsize
) == 2 * wordsize
)
6985 uint32_t *data_p
= (uint32_t *) data
;
6986 if (data_p
[0] == match
)
6994 uint64_t *data_p
= (uint64_t *) data
;
6995 if (data_p
[0] == match
)
7002 offset
+= 2 * wordsize
;
7008 /* See linux-low.h. */
7011 linux_get_hwcap (int wordsize
)
7013 CORE_ADDR hwcap
= 0;
7014 linux_get_auxv (wordsize
, AT_HWCAP
, &hwcap
);
7018 /* See linux-low.h. */
7021 linux_get_hwcap2 (int wordsize
)
7023 CORE_ADDR hwcap2
= 0;
7024 linux_get_auxv (wordsize
, AT_HWCAP2
, &hwcap2
);
7028 #ifdef HAVE_LINUX_REGSETS
7030 initialize_regsets_info (struct regsets_info
*info
)
7032 for (info
->num_regsets
= 0;
7033 info
->regsets
[info
->num_regsets
].size
>= 0;
7034 info
->num_regsets
++)
7040 initialize_low (void)
7042 struct sigaction sigchld_action
;
7044 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7045 set_target_ops (the_linux_target
);
7047 linux_ptrace_init_warnings ();
7048 linux_proc_init_warnings ();
7050 sigchld_action
.sa_handler
= sigchld_handler
;
7051 sigemptyset (&sigchld_action
.sa_mask
);
7052 sigchld_action
.sa_flags
= SA_RESTART
;
7053 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7055 initialize_low_arch ();
7057 linux_check_ptrace_features ();