1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2020 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
22 #include "gdbsupport/agent.h"
24 #include "gdbsupport/rsp-low.h"
25 #include "gdbsupport/signals-state-save-restore.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
28 #include "gdbsupport/gdb_wait.h"
29 #include "nat/gdb_ptrace.h"
30 #include "nat/linux-ptrace.h"
31 #include "nat/linux-procfs.h"
32 #include "nat/linux-personality.h"
34 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
46 #include "gdbsupport/filestuff.h"
47 #include "tracepoint.h"
49 #include "gdbsupport/common-inferior.h"
50 #include "nat/fork-inferior.h"
51 #include "gdbsupport/environ.h"
52 #include "gdbsupport/gdb-sigmask.h"
53 #include "gdbsupport/scoped_restore.h"
55 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
56 then ELFMAG0 will have been defined. If it didn't get included by
57 gdb_proc_service.h then including it will likely introduce a duplicate
58 definition of elf_fpregset_t. */
61 #include "nat/linux-namespaces.h"
63 #ifdef HAVE_PERSONALITY
64 # include <sys/personality.h>
65 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
66 # define ADDR_NO_RANDOMIZE 0x0040000
78 /* Some targets did not define these ptrace constants from the start,
79 so gdbserver defines them locally here. In the future, these may
80 be removed after they are added to asm/ptrace.h. */
81 #if !(defined(PT_TEXT_ADDR) \
82 || defined(PT_DATA_ADDR) \
83 || defined(PT_TEXT_END_ADDR))
84 #if defined(__mcoldfire__)
85 /* These are still undefined in 3.10 kernels. */
86 #define PT_TEXT_ADDR 49*4
87 #define PT_DATA_ADDR 50*4
88 #define PT_TEXT_END_ADDR 51*4
89 /* BFIN already defines these since at least 2.6.32 kernels. */
91 #define PT_TEXT_ADDR 220
92 #define PT_TEXT_END_ADDR 224
93 #define PT_DATA_ADDR 228
94 /* These are still undefined in 3.10 kernels. */
95 #elif defined(__TMS320C6X__)
96 #define PT_TEXT_ADDR (0x10000*4)
97 #define PT_DATA_ADDR (0x10004*4)
98 #define PT_TEXT_END_ADDR (0x10008*4)
102 #if (defined(__UCLIBC__) \
103 && defined(HAS_NOMMU) \
104 && defined(PT_TEXT_ADDR) \
105 && defined(PT_DATA_ADDR) \
106 && defined(PT_TEXT_END_ADDR))
107 #define SUPPORTS_READ_OFFSETS
110 #ifdef HAVE_LINUX_BTRACE
111 # include "nat/linux-btrace.h"
112 # include "gdbsupport/btrace-common.h"
115 #ifndef HAVE_ELF32_AUXV_T
116 /* Copied from glibc's elf.h. */
119 uint32_t a_type
; /* Entry type */
122 uint32_t a_val
; /* Integer value */
123 /* We use to have pointer elements added here. We cannot do that,
124 though, since it does not work when using 32-bit definitions
125 on 64-bit platforms and vice versa. */
130 #ifndef HAVE_ELF64_AUXV_T
131 /* Copied from glibc's elf.h. */
134 uint64_t a_type
; /* Entry type */
137 uint64_t a_val
; /* Integer value */
138 /* We use to have pointer elements added here. We cannot do that,
139 though, since it does not work when using 32-bit definitions
140 on 64-bit platforms and vice versa. */
145 /* Does the current host support PTRACE_GETREGSET? */
146 int have_ptrace_getregset
= -1;
150 /* See nat/linux-nat.h. */
153 ptid_of_lwp (struct lwp_info
*lwp
)
155 return ptid_of (get_lwp_thread (lwp
));
158 /* See nat/linux-nat.h. */
161 lwp_set_arch_private_info (struct lwp_info
*lwp
,
162 struct arch_lwp_info
*info
)
164 lwp
->arch_private
= info
;
167 /* See nat/linux-nat.h. */
169 struct arch_lwp_info
*
170 lwp_arch_private_info (struct lwp_info
*lwp
)
172 return lwp
->arch_private
;
175 /* See nat/linux-nat.h. */
178 lwp_is_stopped (struct lwp_info
*lwp
)
183 /* See nat/linux-nat.h. */
185 enum target_stop_reason
186 lwp_stop_reason (struct lwp_info
*lwp
)
188 return lwp
->stop_reason
;
191 /* See nat/linux-nat.h. */
194 lwp_is_stepping (struct lwp_info
*lwp
)
196 return lwp
->stepping
;
199 /* A list of all unknown processes which receive stop signals. Some
200 other process will presumably claim each of these as forked
201 children momentarily. */
203 struct simple_pid_list
205 /* The process ID. */
208 /* The status as reported by waitpid. */
212 struct simple_pid_list
*next
;
214 struct simple_pid_list
*stopped_pids
;
216 /* Trivial list manipulation functions to keep track of a list of new
217 stopped processes. */
220 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
222 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
225 new_pid
->status
= status
;
226 new_pid
->next
= *listp
;
231 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
233 struct simple_pid_list
**p
;
235 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
236 if ((*p
)->pid
== pid
)
238 struct simple_pid_list
*next
= (*p
)->next
;
240 *statusp
= (*p
)->status
;
248 enum stopping_threads_kind
250 /* Not stopping threads presently. */
251 NOT_STOPPING_THREADS
,
253 /* Stopping threads. */
256 /* Stopping and suspending threads. */
257 STOPPING_AND_SUSPENDING_THREADS
260 /* This is set while stop_all_lwps is in effect. */
261 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
263 /* FIXME make into a target method? */
264 int using_threads
= 1;
266 /* True if we're presently stabilizing threads (moving them out of
268 static int stabilizing_threads
;
270 static void unsuspend_all_lwps (struct lwp_info
*except
);
271 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
272 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
273 static int finish_step_over (struct lwp_info
*lwp
);
274 static int kill_lwp (unsigned long lwpid
, int signo
);
275 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
276 static int linux_low_ptrace_options (int attached
);
277 static int check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
);
279 /* When the event-loop is doing a step-over, this points at the thread
281 ptid_t step_over_bkpt
;
283 /* True if the low target can hardware single-step. */
286 can_hardware_single_step (void)
288 if (the_low_target
.supports_hardware_single_step
!= NULL
)
289 return the_low_target
.supports_hardware_single_step ();
295 linux_process_target::low_supports_breakpoints ()
301 linux_process_target::low_get_pc (regcache
*regcache
)
307 linux_process_target::low_set_pc (regcache
*regcache
, CORE_ADDR newpc
)
309 gdb_assert_not_reached ("linux target op low_set_pc is not implemented");
312 std::vector
<CORE_ADDR
>
313 linux_process_target::low_get_next_pcs (regcache
*regcache
)
315 gdb_assert_not_reached ("linux target op low_get_next_pcs is not "
320 linux_process_target::low_decr_pc_after_break ()
325 /* Returns true if this target can support fast tracepoints. This
326 does not mean that the in-process agent has been loaded in the
330 supports_fast_tracepoints (void)
332 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
335 /* True if LWP is stopped in its stepping range. */
338 lwp_in_step_range (struct lwp_info
*lwp
)
340 CORE_ADDR pc
= lwp
->stop_pc
;
342 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
345 struct pending_signals
349 struct pending_signals
*prev
;
352 /* The read/write ends of the pipe registered as waitable file in the
354 static int linux_event_pipe
[2] = { -1, -1 };
356 /* True if we're currently in async mode. */
357 #define target_is_async_p() (linux_event_pipe[0] != -1)
359 static void send_sigstop (struct lwp_info
*lwp
);
361 /* Return non-zero if HEADER is a 64-bit ELF file. */
364 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
366 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
367 && header
->e_ident
[EI_MAG1
] == ELFMAG1
368 && header
->e_ident
[EI_MAG2
] == ELFMAG2
369 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
371 *machine
= header
->e_machine
;
372 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
379 /* Return non-zero if FILE is a 64-bit ELF file,
380 zero if the file is not a 64-bit ELF file,
381 and -1 if the file is not accessible or doesn't exist. */
384 elf_64_file_p (const char *file
, unsigned int *machine
)
389 fd
= open (file
, O_RDONLY
);
393 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
400 return elf_64_header_p (&header
, machine
);
403 /* Accepts an integer PID; Returns true if the executable PID is
404 running is a 64-bit ELF file.. */
407 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
411 sprintf (file
, "/proc/%d/exe", pid
);
412 return elf_64_file_p (file
, machine
);
416 linux_process_target::delete_lwp (lwp_info
*lwp
)
418 struct thread_info
*thr
= get_lwp_thread (lwp
);
421 debug_printf ("deleting %ld\n", lwpid_of (thr
));
425 low_delete_thread (lwp
->arch_private
);
431 linux_process_target::low_delete_thread (arch_lwp_info
*info
)
433 /* Default implementation should be overridden if architecture-specific
434 info is being used. */
435 gdb_assert (info
== nullptr);
439 linux_process_target::add_linux_process (int pid
, int attached
)
441 struct process_info
*proc
;
443 proc
= add_process (pid
, attached
);
444 proc
->priv
= XCNEW (struct process_info_private
);
446 proc
->priv
->arch_private
= low_new_process ();
452 linux_process_target::low_new_process ()
458 linux_process_target::low_delete_process (arch_process_info
*info
)
460 /* Default implementation must be overridden if architecture-specific
462 gdb_assert (info
== nullptr);
466 linux_process_target::low_new_fork (process_info
*parent
, process_info
*child
)
472 linux_process_target::arch_setup_thread (thread_info
*thread
)
474 struct thread_info
*saved_thread
;
476 saved_thread
= current_thread
;
477 current_thread
= thread
;
481 current_thread
= saved_thread
;
485 linux_process_target::handle_extended_wait (lwp_info
**orig_event_lwp
,
488 client_state
&cs
= get_client_state ();
489 struct lwp_info
*event_lwp
= *orig_event_lwp
;
490 int event
= linux_ptrace_get_extended_event (wstat
);
491 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
492 struct lwp_info
*new_lwp
;
494 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
496 /* All extended events we currently use are mid-syscall. Only
497 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
498 you have to be using PTRACE_SEIZE to get that. */
499 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
501 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
502 || (event
== PTRACE_EVENT_CLONE
))
505 unsigned long new_pid
;
508 /* Get the pid of the new lwp. */
509 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
512 /* If we haven't already seen the new PID stop, wait for it now. */
513 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
515 /* The new child has a pending SIGSTOP. We can't affect it until it
516 hits the SIGSTOP, but we're already attached. */
518 ret
= my_waitpid (new_pid
, &status
, __WALL
);
521 perror_with_name ("waiting for new child");
522 else if (ret
!= new_pid
)
523 warning ("wait returned unexpected PID %d", ret
);
524 else if (!WIFSTOPPED (status
))
525 warning ("wait returned unexpected status 0x%x", status
);
528 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
530 struct process_info
*parent_proc
;
531 struct process_info
*child_proc
;
532 struct lwp_info
*child_lwp
;
533 struct thread_info
*child_thr
;
534 struct target_desc
*tdesc
;
536 ptid
= ptid_t (new_pid
, new_pid
, 0);
540 debug_printf ("HEW: Got fork event from LWP %ld, "
542 ptid_of (event_thr
).lwp (),
546 /* Add the new process to the tables and clone the breakpoint
547 lists of the parent. We need to do this even if the new process
548 will be detached, since we will need the process object and the
549 breakpoints to remove any breakpoints from memory when we
550 detach, and the client side will access registers. */
551 child_proc
= add_linux_process (new_pid
, 0);
552 gdb_assert (child_proc
!= NULL
);
553 child_lwp
= add_lwp (ptid
);
554 gdb_assert (child_lwp
!= NULL
);
555 child_lwp
->stopped
= 1;
556 child_lwp
->must_set_ptrace_flags
= 1;
557 child_lwp
->status_pending_p
= 0;
558 child_thr
= get_lwp_thread (child_lwp
);
559 child_thr
->last_resume_kind
= resume_stop
;
560 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
562 /* If we're suspending all threads, leave this one suspended
563 too. If the fork/clone parent is stepping over a breakpoint,
564 all other threads have been suspended already. Leave the
565 child suspended too. */
566 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
567 || event_lwp
->bp_reinsert
!= 0)
570 debug_printf ("HEW: leaving child suspended\n");
571 child_lwp
->suspended
= 1;
574 parent_proc
= get_thread_process (event_thr
);
575 child_proc
->attached
= parent_proc
->attached
;
577 if (event_lwp
->bp_reinsert
!= 0
578 && supports_software_single_step ()
579 && event
== PTRACE_EVENT_VFORK
)
581 /* If we leave single-step breakpoints there, child will
582 hit it, so uninsert single-step breakpoints from parent
583 (and child). Once vfork child is done, reinsert
584 them back to parent. */
585 uninsert_single_step_breakpoints (event_thr
);
588 clone_all_breakpoints (child_thr
, event_thr
);
590 tdesc
= allocate_target_description ();
591 copy_target_description (tdesc
, parent_proc
->tdesc
);
592 child_proc
->tdesc
= tdesc
;
594 /* Clone arch-specific process data. */
595 low_new_fork (parent_proc
, child_proc
);
597 /* Save fork info in the parent thread. */
598 if (event
== PTRACE_EVENT_FORK
)
599 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
600 else if (event
== PTRACE_EVENT_VFORK
)
601 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
603 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
605 /* The status_pending field contains bits denoting the
606 extended event, so when the pending event is handled,
607 the handler will look at lwp->waitstatus. */
608 event_lwp
->status_pending_p
= 1;
609 event_lwp
->status_pending
= wstat
;
611 /* Link the threads until the parent event is passed on to
613 event_lwp
->fork_relative
= child_lwp
;
614 child_lwp
->fork_relative
= event_lwp
;
616 /* If the parent thread is doing step-over with single-step
617 breakpoints, the list of single-step breakpoints are cloned
618 from the parent's. Remove them from the child process.
619 In case of vfork, we'll reinsert them back once vforked
621 if (event_lwp
->bp_reinsert
!= 0
622 && supports_software_single_step ())
624 /* The child process is forked and stopped, so it is safe
625 to access its memory without stopping all other threads
626 from other processes. */
627 delete_single_step_breakpoints (child_thr
);
629 gdb_assert (has_single_step_breakpoints (event_thr
));
630 gdb_assert (!has_single_step_breakpoints (child_thr
));
633 /* Report the event. */
638 debug_printf ("HEW: Got clone event "
639 "from LWP %ld, new child is LWP %ld\n",
640 lwpid_of (event_thr
), new_pid
);
642 ptid
= ptid_t (pid_of (event_thr
), new_pid
, 0);
643 new_lwp
= add_lwp (ptid
);
645 /* Either we're going to immediately resume the new thread
646 or leave it stopped. resume_one_lwp is a nop if it
647 thinks the thread is currently running, so set this first
648 before calling resume_one_lwp. */
649 new_lwp
->stopped
= 1;
651 /* If we're suspending all threads, leave this one suspended
652 too. If the fork/clone parent is stepping over a breakpoint,
653 all other threads have been suspended already. Leave the
654 child suspended too. */
655 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
656 || event_lwp
->bp_reinsert
!= 0)
657 new_lwp
->suspended
= 1;
659 /* Normally we will get the pending SIGSTOP. But in some cases
660 we might get another signal delivered to the group first.
661 If we do get another signal, be sure not to lose it. */
662 if (WSTOPSIG (status
) != SIGSTOP
)
664 new_lwp
->stop_expected
= 1;
665 new_lwp
->status_pending_p
= 1;
666 new_lwp
->status_pending
= status
;
668 else if (cs
.report_thread_events
)
670 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
671 new_lwp
->status_pending_p
= 1;
672 new_lwp
->status_pending
= status
;
676 thread_db_notice_clone (event_thr
, ptid
);
679 /* Don't report the event. */
682 else if (event
== PTRACE_EVENT_VFORK_DONE
)
684 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
686 if (event_lwp
->bp_reinsert
!= 0 && supports_software_single_step ())
688 reinsert_single_step_breakpoints (event_thr
);
690 gdb_assert (has_single_step_breakpoints (event_thr
));
693 /* Report the event. */
696 else if (event
== PTRACE_EVENT_EXEC
&& cs
.report_exec_events
)
698 struct process_info
*proc
;
699 std::vector
<int> syscalls_to_catch
;
705 debug_printf ("HEW: Got exec event from LWP %ld\n",
706 lwpid_of (event_thr
));
709 /* Get the event ptid. */
710 event_ptid
= ptid_of (event_thr
);
711 event_pid
= event_ptid
.pid ();
713 /* Save the syscall list from the execing process. */
714 proc
= get_thread_process (event_thr
);
715 syscalls_to_catch
= std::move (proc
->syscalls_to_catch
);
717 /* Delete the execing process and all its threads. */
719 current_thread
= NULL
;
721 /* Create a new process/lwp/thread. */
722 proc
= add_linux_process (event_pid
, 0);
723 event_lwp
= add_lwp (event_ptid
);
724 event_thr
= get_lwp_thread (event_lwp
);
725 gdb_assert (current_thread
== event_thr
);
726 arch_setup_thread (event_thr
);
728 /* Set the event status. */
729 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
730 event_lwp
->waitstatus
.value
.execd_pathname
731 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
733 /* Mark the exec status as pending. */
734 event_lwp
->stopped
= 1;
735 event_lwp
->status_pending_p
= 1;
736 event_lwp
->status_pending
= wstat
;
737 event_thr
->last_resume_kind
= resume_continue
;
738 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
740 /* Update syscall state in the new lwp, effectively mid-syscall too. */
741 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
743 /* Restore the list to catch. Don't rely on the client, which is free
744 to avoid sending a new list when the architecture doesn't change.
745 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
746 proc
->syscalls_to_catch
= std::move (syscalls_to_catch
);
748 /* Report the event. */
749 *orig_event_lwp
= event_lwp
;
753 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
757 linux_process_target::get_pc (lwp_info
*lwp
)
759 struct thread_info
*saved_thread
;
760 struct regcache
*regcache
;
763 if (!low_supports_breakpoints ())
766 saved_thread
= current_thread
;
767 current_thread
= get_lwp_thread (lwp
);
769 regcache
= get_thread_regcache (current_thread
, 1);
770 pc
= low_get_pc (regcache
);
773 debug_printf ("pc is 0x%lx\n", (long) pc
);
775 current_thread
= saved_thread
;
779 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
780 Fill *SYSNO with the syscall nr trapped. */
783 get_syscall_trapinfo (struct lwp_info
*lwp
, int *sysno
)
785 struct thread_info
*saved_thread
;
786 struct regcache
*regcache
;
788 if (the_low_target
.get_syscall_trapinfo
== NULL
)
790 /* If we cannot get the syscall trapinfo, report an unknown
791 system call number. */
792 *sysno
= UNKNOWN_SYSCALL
;
796 saved_thread
= current_thread
;
797 current_thread
= get_lwp_thread (lwp
);
799 regcache
= get_thread_regcache (current_thread
, 1);
800 (*the_low_target
.get_syscall_trapinfo
) (regcache
, sysno
);
803 debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno
);
805 current_thread
= saved_thread
;
809 linux_process_target::save_stop_reason (lwp_info
*lwp
)
812 CORE_ADDR sw_breakpoint_pc
;
813 struct thread_info
*saved_thread
;
814 #if USE_SIGTRAP_SIGINFO
818 if (!low_supports_breakpoints ())
822 sw_breakpoint_pc
= pc
- low_decr_pc_after_break ();
824 /* breakpoint_at reads from the current thread. */
825 saved_thread
= current_thread
;
826 current_thread
= get_lwp_thread (lwp
);
828 #if USE_SIGTRAP_SIGINFO
829 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
830 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
832 if (siginfo
.si_signo
== SIGTRAP
)
834 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
835 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
837 /* The si_code is ambiguous on this arch -- check debug
839 if (!check_stopped_by_watchpoint (lwp
))
840 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
842 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
844 /* If we determine the LWP stopped for a SW breakpoint,
845 trust it. Particularly don't check watchpoint
846 registers, because at least on s390, we'd find
847 stopped-by-watchpoint as long as there's a watchpoint
849 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
851 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
853 /* This can indicate either a hardware breakpoint or
854 hardware watchpoint. Check debug registers. */
855 if (!check_stopped_by_watchpoint (lwp
))
856 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
858 else if (siginfo
.si_code
== TRAP_TRACE
)
860 /* We may have single stepped an instruction that
861 triggered a watchpoint. In that case, on some
862 architectures (such as x86), instead of TRAP_HWBKPT,
863 si_code indicates TRAP_TRACE, and we need to check
864 the debug registers separately. */
865 if (!check_stopped_by_watchpoint (lwp
))
866 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
871 /* We may have just stepped a breakpoint instruction. E.g., in
872 non-stop mode, GDB first tells the thread A to step a range, and
873 then the user inserts a breakpoint inside the range. In that
874 case we need to report the breakpoint PC. */
875 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
876 && low_breakpoint_at (sw_breakpoint_pc
))
877 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
879 if (hardware_breakpoint_inserted_here (pc
))
880 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
882 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
883 check_stopped_by_watchpoint (lwp
);
886 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
890 struct thread_info
*thr
= get_lwp_thread (lwp
);
892 debug_printf ("CSBB: %s stopped by software breakpoint\n",
893 target_pid_to_str (ptid_of (thr
)));
896 /* Back up the PC if necessary. */
897 if (pc
!= sw_breakpoint_pc
)
899 struct regcache
*regcache
900 = get_thread_regcache (current_thread
, 1);
901 low_set_pc (regcache
, sw_breakpoint_pc
);
904 /* Update this so we record the correct stop PC below. */
905 pc
= sw_breakpoint_pc
;
907 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
911 struct thread_info
*thr
= get_lwp_thread (lwp
);
913 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
914 target_pid_to_str (ptid_of (thr
)));
917 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
921 struct thread_info
*thr
= get_lwp_thread (lwp
);
923 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
924 target_pid_to_str (ptid_of (thr
)));
927 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
931 struct thread_info
*thr
= get_lwp_thread (lwp
);
933 debug_printf ("CSBB: %s stopped by trace\n",
934 target_pid_to_str (ptid_of (thr
)));
939 current_thread
= saved_thread
;
944 linux_process_target::add_lwp (ptid_t ptid
)
946 struct lwp_info
*lwp
;
948 lwp
= XCNEW (struct lwp_info
);
950 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
952 lwp
->thread
= add_thread (ptid
, lwp
);
954 low_new_thread (lwp
);
960 linux_process_target::low_new_thread (lwp_info
*info
)
965 /* Callback to be used when calling fork_inferior, responsible for
966 actually initiating the tracing of the inferior. */
971 if (ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0,
972 (PTRACE_TYPE_ARG4
) 0) < 0)
973 trace_start_error_with_name ("ptrace");
975 if (setpgid (0, 0) < 0)
976 trace_start_error_with_name ("setpgid");
978 /* If GDBserver is connected to gdb via stdio, redirect the inferior's
979 stdout to stderr so that inferior i/o doesn't corrupt the connection.
980 Also, redirect stdin to /dev/null. */
981 if (remote_connection_is_stdio ())
984 trace_start_error_with_name ("close");
985 if (open ("/dev/null", O_RDONLY
) < 0)
986 trace_start_error_with_name ("open");
988 trace_start_error_with_name ("dup2");
989 if (write (2, "stdin/stdout redirected\n",
990 sizeof ("stdin/stdout redirected\n") - 1) < 0)
992 /* Errors ignored. */;
997 /* Start an inferior process and returns its pid.
998 PROGRAM is the name of the program to be started, and PROGRAM_ARGS
999 are its arguments. */
1002 linux_process_target::create_inferior (const char *program
,
1003 const std::vector
<char *> &program_args
)
1005 client_state
&cs
= get_client_state ();
1006 struct lwp_info
*new_lwp
;
1011 maybe_disable_address_space_randomization restore_personality
1012 (cs
.disable_randomization
);
1013 std::string str_program_args
= stringify_argv (program_args
);
1015 pid
= fork_inferior (program
,
1016 str_program_args
.c_str (),
1017 get_environ ()->envp (), linux_ptrace_fun
,
1018 NULL
, NULL
, NULL
, NULL
);
1021 add_linux_process (pid
, 0);
1023 ptid
= ptid_t (pid
, pid
, 0);
1024 new_lwp
= add_lwp (ptid
);
1025 new_lwp
->must_set_ptrace_flags
= 1;
1027 post_fork_inferior (pid
, program
);
1032 /* Implement the post_create_inferior target_ops method. */
1035 linux_process_target::post_create_inferior ()
1037 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
1041 if (lwp
->must_set_ptrace_flags
)
1043 struct process_info
*proc
= current_process ();
1044 int options
= linux_low_ptrace_options (proc
->attached
);
1046 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
1047 lwp
->must_set_ptrace_flags
= 0;
1052 linux_process_target::attach_lwp (ptid_t ptid
)
1054 struct lwp_info
*new_lwp
;
1055 int lwpid
= ptid
.lwp ();
1057 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
1061 new_lwp
= add_lwp (ptid
);
1063 /* We need to wait for SIGSTOP before being able to make the next
1064 ptrace call on this LWP. */
1065 new_lwp
->must_set_ptrace_flags
= 1;
1067 if (linux_proc_pid_is_stopped (lwpid
))
1070 debug_printf ("Attached to a stopped process\n");
1072 /* The process is definitely stopped. It is in a job control
1073 stop, unless the kernel predates the TASK_STOPPED /
1074 TASK_TRACED distinction, in which case it might be in a
1075 ptrace stop. Make sure it is in a ptrace stop; from there we
1076 can kill it, signal it, et cetera.
1078 First make sure there is a pending SIGSTOP. Since we are
1079 already attached, the process can not transition from stopped
1080 to running without a PTRACE_CONT; so we know this signal will
1081 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1082 probably already in the queue (unless this kernel is old
1083 enough to use TASK_STOPPED for ptrace stops); but since
1084 SIGSTOP is not an RT signal, it can only be queued once. */
1085 kill_lwp (lwpid
, SIGSTOP
);
1087 /* Finally, resume the stopped process. This will deliver the
1088 SIGSTOP (or a higher priority signal, just like normal
1089 PTRACE_ATTACH), which we'll catch later on. */
1090 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1093 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1094 brings it to a halt.
1096 There are several cases to consider here:
1098 1) gdbserver has already attached to the process and is being notified
1099 of a new thread that is being created.
1100 In this case we should ignore that SIGSTOP and resume the
1101 process. This is handled below by setting stop_expected = 1,
1102 and the fact that add_thread sets last_resume_kind ==
1105 2) This is the first thread (the process thread), and we're attaching
1106 to it via attach_inferior.
1107 In this case we want the process thread to stop.
1108 This is handled by having linux_attach set last_resume_kind ==
1109 resume_stop after we return.
1111 If the pid we are attaching to is also the tgid, we attach to and
1112 stop all the existing threads. Otherwise, we attach to pid and
1113 ignore any other threads in the same group as this pid.
1115 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1117 In this case we want the thread to stop.
1118 FIXME: This case is currently not properly handled.
1119 We should wait for the SIGSTOP but don't. Things work apparently
1120 because enough time passes between when we ptrace (ATTACH) and when
1121 gdb makes the next ptrace call on the thread.
1123 On the other hand, if we are currently trying to stop all threads, we
1124 should treat the new thread as if we had sent it a SIGSTOP. This works
1125 because we are guaranteed that the add_lwp call above added us to the
1126 end of the list, and so the new thread has not yet reached
1127 wait_for_sigstop (but will). */
1128 new_lwp
->stop_expected
= 1;
1133 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1134 already attached. Returns true if a new LWP is found, false
1138 attach_proc_task_lwp_callback (ptid_t ptid
)
1140 /* Is this a new thread? */
1141 if (find_thread_ptid (ptid
) == NULL
)
1143 int lwpid
= ptid
.lwp ();
1147 debug_printf ("Found new lwp %d\n", lwpid
);
1149 err
= the_linux_target
->attach_lwp (ptid
);
1151 /* Be quiet if we simply raced with the thread exiting. EPERM
1152 is returned if the thread's task still exists, and is marked
1153 as exited or zombie, as well as other conditions, so in that
1154 case, confirm the status in /proc/PID/status. */
1156 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1160 debug_printf ("Cannot attach to lwp %d: "
1161 "thread is gone (%d: %s)\n",
1162 lwpid
, err
, safe_strerror (err
));
1168 = linux_ptrace_attach_fail_reason_string (ptid
, err
);
1170 warning (_("Cannot attach to lwp %d: %s"), lwpid
, reason
.c_str ());
1178 static void async_file_mark (void);
1180 /* Attach to PID. If PID is the tgid, attach to it and all
1184 linux_process_target::attach (unsigned long pid
)
1186 struct process_info
*proc
;
1187 struct thread_info
*initial_thread
;
1188 ptid_t ptid
= ptid_t (pid
, pid
, 0);
1191 proc
= add_linux_process (pid
, 1);
1193 /* Attach to PID. We will check for other threads
1195 err
= attach_lwp (ptid
);
1198 remove_process (proc
);
1200 std::string reason
= linux_ptrace_attach_fail_reason_string (ptid
, err
);
1201 error ("Cannot attach to process %ld: %s", pid
, reason
.c_str ());
1204 /* Don't ignore the initial SIGSTOP if we just attached to this
1205 process. It will be collected by wait shortly. */
1206 initial_thread
= find_thread_ptid (ptid_t (pid
, pid
, 0));
1207 initial_thread
->last_resume_kind
= resume_stop
;
1209 /* We must attach to every LWP. If /proc is mounted, use that to
1210 find them now. On the one hand, the inferior may be using raw
1211 clone instead of using pthreads. On the other hand, even if it
1212 is using pthreads, GDB may not be connected yet (thread_db needs
1213 to do symbol lookups, through qSymbol). Also, thread_db walks
1214 structures in the inferior's address space to find the list of
1215 threads/LWPs, and those structures may well be corrupted. Note
1216 that once thread_db is loaded, we'll still use it to list threads
1217 and associate pthread info with each LWP. */
1218 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1220 /* GDB will shortly read the xml target description for this
1221 process, to figure out the process' architecture. But the target
1222 description is only filled in when the first process/thread in
1223 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1224 that now, otherwise, if GDB is fast enough, it could read the
1225 target description _before_ that initial stop. */
1228 struct lwp_info
*lwp
;
1230 ptid_t pid_ptid
= ptid_t (pid
);
1232 lwpid
= wait_for_event_filtered (pid_ptid
, pid_ptid
, &wstat
, __WALL
);
1233 gdb_assert (lwpid
> 0);
1235 lwp
= find_lwp_pid (ptid_t (lwpid
));
1237 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1239 lwp
->status_pending_p
= 1;
1240 lwp
->status_pending
= wstat
;
1243 initial_thread
->last_resume_kind
= resume_continue
;
1247 gdb_assert (proc
->tdesc
!= NULL
);
1254 last_thread_of_process_p (int pid
)
1256 bool seen_one
= false;
1258 thread_info
*thread
= find_thread (pid
, [&] (thread_info
*thr_arg
)
1262 /* This is the first thread of this process we see. */
1268 /* This is the second thread of this process we see. */
1273 return thread
== NULL
;
1279 linux_kill_one_lwp (struct lwp_info
*lwp
)
1281 struct thread_info
*thr
= get_lwp_thread (lwp
);
1282 int pid
= lwpid_of (thr
);
1284 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1285 there is no signal context, and ptrace(PTRACE_KILL) (or
1286 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1287 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1288 alternative is to kill with SIGKILL. We only need one SIGKILL
1289 per process, not one for each thread. But since we still support
1290 support debugging programs using raw clone without CLONE_THREAD,
1291 we send one for each thread. For years, we used PTRACE_KILL
1292 only, so we're being a bit paranoid about some old kernels where
1293 PTRACE_KILL might work better (dubious if there are any such, but
1294 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1295 second, and so we're fine everywhere. */
1298 kill_lwp (pid
, SIGKILL
);
1301 int save_errno
= errno
;
1303 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1304 target_pid_to_str (ptid_of (thr
)),
1305 save_errno
? safe_strerror (save_errno
) : "OK");
1309 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1312 int save_errno
= errno
;
1314 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1315 target_pid_to_str (ptid_of (thr
)),
1316 save_errno
? safe_strerror (save_errno
) : "OK");
1320 /* Kill LWP and wait for it to die. */
1323 kill_wait_lwp (struct lwp_info
*lwp
)
1325 struct thread_info
*thr
= get_lwp_thread (lwp
);
1326 int pid
= ptid_of (thr
).pid ();
1327 int lwpid
= ptid_of (thr
).lwp ();
1332 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1336 linux_kill_one_lwp (lwp
);
1338 /* Make sure it died. Notes:
1340 - The loop is most likely unnecessary.
1342 - We don't use wait_for_event as that could delete lwps
1343 while we're iterating over them. We're not interested in
1344 any pending status at this point, only in making sure all
1345 wait status on the kernel side are collected until the
1348 - We don't use __WALL here as the __WALL emulation relies on
1349 SIGCHLD, and killing a stopped process doesn't generate
1350 one, nor an exit status.
1352 res
= my_waitpid (lwpid
, &wstat
, 0);
1353 if (res
== -1 && errno
== ECHILD
)
1354 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1355 } while (res
> 0 && WIFSTOPPED (wstat
));
1357 /* Even if it was stopped, the child may have already disappeared.
1358 E.g., if it was killed by SIGKILL. */
1359 if (res
< 0 && errno
!= ECHILD
)
1360 perror_with_name ("kill_wait_lwp");
1363 /* Callback for `for_each_thread'. Kills an lwp of a given process,
1364 except the leader. */
1367 kill_one_lwp_callback (thread_info
*thread
, int pid
)
1369 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1371 /* We avoid killing the first thread here, because of a Linux kernel (at
1372 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1373 the children get a chance to be reaped, it will remain a zombie
1376 if (lwpid_of (thread
) == pid
)
1379 debug_printf ("lkop: is last of process %s\n",
1380 target_pid_to_str (thread
->id
));
1384 kill_wait_lwp (lwp
);
1388 linux_process_target::kill (process_info
*process
)
1390 int pid
= process
->pid
;
1392 /* If we're killing a running inferior, make sure it is stopped
1393 first, as PTRACE_KILL will not work otherwise. */
1394 stop_all_lwps (0, NULL
);
1396 for_each_thread (pid
, [&] (thread_info
*thread
)
1398 kill_one_lwp_callback (thread
, pid
);
1401 /* See the comment in linux_kill_one_lwp. We did not kill the first
1402 thread in the list, so do so now. */
1403 lwp_info
*lwp
= find_lwp_pid (ptid_t (pid
));
1408 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1412 kill_wait_lwp (lwp
);
1416 /* Since we presently can only stop all lwps of all processes, we
1417 need to unstop lwps of other processes. */
1418 unstop_all_lwps (0, NULL
);
1422 /* Get pending signal of THREAD, for detaching purposes. This is the
1423 signal the thread last stopped for, which we need to deliver to the
1424 thread when detaching, otherwise, it'd be suppressed/lost. */
1427 get_detach_signal (struct thread_info
*thread
)
1429 client_state
&cs
= get_client_state ();
1430 enum gdb_signal signo
= GDB_SIGNAL_0
;
1432 struct lwp_info
*lp
= get_thread_lwp (thread
);
1434 if (lp
->status_pending_p
)
1435 status
= lp
->status_pending
;
1438 /* If the thread had been suspended by gdbserver, and it stopped
1439 cleanly, then it'll have stopped with SIGSTOP. But we don't
1440 want to deliver that SIGSTOP. */
1441 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1442 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1445 /* Otherwise, we may need to deliver the signal we
1447 status
= lp
->last_status
;
1450 if (!WIFSTOPPED (status
))
1453 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1454 target_pid_to_str (ptid_of (thread
)));
1458 /* Extended wait statuses aren't real SIGTRAPs. */
1459 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1462 debug_printf ("GPS: lwp %s had stopped with extended "
1463 "status: no pending signal\n",
1464 target_pid_to_str (ptid_of (thread
)));
1468 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1470 if (cs
.program_signals_p
&& !cs
.program_signals
[signo
])
1473 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1474 target_pid_to_str (ptid_of (thread
)),
1475 gdb_signal_to_string (signo
));
1478 else if (!cs
.program_signals_p
1479 /* If we have no way to know which signals GDB does not
1480 want to have passed to the program, assume
1481 SIGTRAP/SIGINT, which is GDB's default. */
1482 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1485 debug_printf ("GPS: lwp %s had signal %s, "
1486 "but we don't know if we should pass it. "
1487 "Default to not.\n",
1488 target_pid_to_str (ptid_of (thread
)),
1489 gdb_signal_to_string (signo
));
1495 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1496 target_pid_to_str (ptid_of (thread
)),
1497 gdb_signal_to_string (signo
));
1499 return WSTOPSIG (status
);
1504 linux_process_target::detach_one_lwp (lwp_info
*lwp
)
1506 struct thread_info
*thread
= get_lwp_thread (lwp
);
1510 /* If there is a pending SIGSTOP, get rid of it. */
1511 if (lwp
->stop_expected
)
1514 debug_printf ("Sending SIGCONT to %s\n",
1515 target_pid_to_str (ptid_of (thread
)));
1517 kill_lwp (lwpid_of (thread
), SIGCONT
);
1518 lwp
->stop_expected
= 0;
1521 /* Pass on any pending signal for this thread. */
1522 sig
= get_detach_signal (thread
);
1524 /* Preparing to resume may try to write registers, and fail if the
1525 lwp is zombie. If that happens, ignore the error. We'll handle
1526 it below, when detach fails with ESRCH. */
1529 /* Flush any pending changes to the process's registers. */
1530 regcache_invalidate_thread (thread
);
1532 /* Finally, let it resume. */
1533 if (the_low_target
.prepare_to_resume
!= NULL
)
1534 the_low_target
.prepare_to_resume (lwp
);
1536 catch (const gdb_exception_error
&ex
)
1538 if (!check_ptrace_stopped_lwp_gone (lwp
))
1542 lwpid
= lwpid_of (thread
);
1543 if (ptrace (PTRACE_DETACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0,
1544 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1546 int save_errno
= errno
;
1548 /* We know the thread exists, so ESRCH must mean the lwp is
1549 zombie. This can happen if one of the already-detached
1550 threads exits the whole thread group. In that case we're
1551 still attached, and must reap the lwp. */
1552 if (save_errno
== ESRCH
)
1556 ret
= my_waitpid (lwpid
, &status
, __WALL
);
1559 warning (_("Couldn't reap LWP %d while detaching: %s"),
1560 lwpid
, safe_strerror (errno
));
1562 else if (!WIFEXITED (status
) && !WIFSIGNALED (status
))
1564 warning (_("Reaping LWP %d while detaching "
1565 "returned unexpected status 0x%x"),
1571 error (_("Can't detach %s: %s"),
1572 target_pid_to_str (ptid_of (thread
)),
1573 safe_strerror (save_errno
));
1576 else if (debug_threads
)
1578 debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
1579 target_pid_to_str (ptid_of (thread
)),
1587 linux_process_target::detach (process_info
*process
)
1589 struct lwp_info
*main_lwp
;
1591 /* As there's a step over already in progress, let it finish first,
1592 otherwise nesting a stabilize_threads operation on top gets real
1594 complete_ongoing_step_over ();
1596 /* Stop all threads before detaching. First, ptrace requires that
1597 the thread is stopped to successfully detach. Second, thread_db
1598 may need to uninstall thread event breakpoints from memory, which
1599 only works with a stopped process anyway. */
1600 stop_all_lwps (0, NULL
);
1602 #ifdef USE_THREAD_DB
1603 thread_db_detach (process
);
1606 /* Stabilize threads (move out of jump pads). */
1607 target_stabilize_threads ();
1609 /* Detach from the clone lwps first. If the thread group exits just
1610 while we're detaching, we must reap the clone lwps before we're
1611 able to reap the leader. */
1612 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1614 /* We don't actually detach from the thread group leader just yet.
1615 If the thread group exits, we must reap the zombie clone lwps
1616 before we're able to reap the leader. */
1617 if (thread
->id
.pid () == thread
->id
.lwp ())
1620 lwp_info
*lwp
= get_thread_lwp (thread
);
1621 detach_one_lwp (lwp
);
1624 main_lwp
= find_lwp_pid (ptid_t (process
->pid
));
1625 detach_one_lwp (main_lwp
);
1629 /* Since we presently can only stop all lwps of all processes, we
1630 need to unstop lwps of other processes. */
1631 unstop_all_lwps (0, NULL
);
1635 /* Remove all LWPs that belong to process PROC from the lwp list. */
1638 linux_process_target::mourn (process_info
*process
)
1640 struct process_info_private
*priv
;
1642 #ifdef USE_THREAD_DB
1643 thread_db_mourn (process
);
1646 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1648 delete_lwp (get_thread_lwp (thread
));
1651 /* Freeing all private data. */
1652 priv
= process
->priv
;
1653 low_delete_process (priv
->arch_private
);
1655 process
->priv
= NULL
;
1657 remove_process (process
);
1661 linux_process_target::join (int pid
)
1666 ret
= my_waitpid (pid
, &status
, 0);
1667 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1669 } while (ret
!= -1 || errno
!= ECHILD
);
1672 /* Return true if the given thread is still alive. */
1675 linux_process_target::thread_alive (ptid_t ptid
)
1677 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1679 /* We assume we always know if a thread exits. If a whole process
1680 exited but we still haven't been able to report it to GDB, we'll
1681 hold on to the last lwp of the dead process. */
1683 return !lwp_is_marked_dead (lwp
);
1689 linux_process_target::thread_still_has_status_pending (thread_info
*thread
)
1691 struct lwp_info
*lp
= get_thread_lwp (thread
);
1693 if (!lp
->status_pending_p
)
1696 if (thread
->last_resume_kind
!= resume_stop
1697 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1698 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1700 struct thread_info
*saved_thread
;
1704 gdb_assert (lp
->last_status
!= 0);
1708 saved_thread
= current_thread
;
1709 current_thread
= thread
;
1711 if (pc
!= lp
->stop_pc
)
1714 debug_printf ("PC of %ld changed\n",
1719 #if !USE_SIGTRAP_SIGINFO
1720 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1721 && !low_breakpoint_at (pc
))
1724 debug_printf ("previous SW breakpoint of %ld gone\n",
1728 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1729 && !hardware_breakpoint_inserted_here (pc
))
1732 debug_printf ("previous HW breakpoint of %ld gone\n",
1738 current_thread
= saved_thread
;
1743 debug_printf ("discarding pending breakpoint status\n");
1744 lp
->status_pending_p
= 0;
1752 /* Returns true if LWP is resumed from the client's perspective. */
1755 lwp_resumed (struct lwp_info
*lwp
)
1757 struct thread_info
*thread
= get_lwp_thread (lwp
);
1759 if (thread
->last_resume_kind
!= resume_stop
)
1762 /* Did gdb send us a `vCont;t', but we haven't reported the
1763 corresponding stop to gdb yet? If so, the thread is still
1764 resumed/running from gdb's perspective. */
1765 if (thread
->last_resume_kind
== resume_stop
1766 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1773 linux_process_target::status_pending_p_callback (thread_info
*thread
,
1776 struct lwp_info
*lp
= get_thread_lwp (thread
);
1778 /* Check if we're only interested in events from a specific process
1779 or a specific LWP. */
1780 if (!thread
->id
.matches (ptid
))
1783 if (!lwp_resumed (lp
))
1786 if (lp
->status_pending_p
1787 && !thread_still_has_status_pending (thread
))
1789 resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1793 return lp
->status_pending_p
;
1797 find_lwp_pid (ptid_t ptid
)
1799 thread_info
*thread
= find_thread ([&] (thread_info
*thr_arg
)
1801 int lwp
= ptid
.lwp () != 0 ? ptid
.lwp () : ptid
.pid ();
1802 return thr_arg
->id
.lwp () == lwp
;
1808 return get_thread_lwp (thread
);
1811 /* Return the number of known LWPs in the tgid given by PID. */
1818 for_each_thread (pid
, [&] (thread_info
*thread
)
1826 /* See nat/linux-nat.h. */
1829 iterate_over_lwps (ptid_t filter
,
1830 gdb::function_view
<iterate_over_lwps_ftype
> callback
)
1832 thread_info
*thread
= find_thread (filter
, [&] (thread_info
*thr_arg
)
1834 lwp_info
*lwp
= get_thread_lwp (thr_arg
);
1836 return callback (lwp
);
1842 return get_thread_lwp (thread
);
1846 linux_process_target::check_zombie_leaders ()
1848 for_each_process ([this] (process_info
*proc
) {
1849 pid_t leader_pid
= pid_of (proc
);
1850 struct lwp_info
*leader_lp
;
1852 leader_lp
= find_lwp_pid (ptid_t (leader_pid
));
1855 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1856 "num_lwps=%d, zombie=%d\n",
1857 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1858 linux_proc_pid_is_zombie (leader_pid
));
1860 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1861 /* Check if there are other threads in the group, as we may
1862 have raced with the inferior simply exiting. */
1863 && !last_thread_of_process_p (leader_pid
)
1864 && linux_proc_pid_is_zombie (leader_pid
))
1866 /* A leader zombie can mean one of two things:
1868 - It exited, and there's an exit status pending
1869 available, or only the leader exited (not the whole
1870 program). In the latter case, we can't waitpid the
1871 leader's exit status until all other threads are gone.
1873 - There are 3 or more threads in the group, and a thread
1874 other than the leader exec'd. On an exec, the Linux
1875 kernel destroys all other threads (except the execing
1876 one) in the thread group, and resets the execing thread's
1877 tid to the tgid. No exit notification is sent for the
1878 execing thread -- from the ptracer's perspective, it
1879 appears as though the execing thread just vanishes.
1880 Until we reap all other threads except the leader and the
1881 execing thread, the leader will be zombie, and the
1882 execing thread will be in `D (disc sleep)'. As soon as
1883 all other threads are reaped, the execing thread changes
1884 it's tid to the tgid, and the previous (zombie) leader
1885 vanishes, giving place to the "new" leader. We could try
1886 distinguishing the exit and exec cases, by waiting once
1887 more, and seeing if something comes out, but it doesn't
1888 sound useful. The previous leader _does_ go away, and
1889 we'll re-add the new one once we see the exec event
1890 (which is just the same as what would happen if the
1891 previous leader did exit voluntarily before some other
1895 debug_printf ("CZL: Thread group leader %d zombie "
1896 "(it exited, or another thread execd).\n",
1899 delete_lwp (leader_lp
);
1904 /* Callback for `find_thread'. Returns the first LWP that is not
1908 not_stopped_callback (thread_info
*thread
, ptid_t filter
)
1910 if (!thread
->id
.matches (filter
))
1913 lwp_info
*lwp
= get_thread_lwp (thread
);
1915 return !lwp
->stopped
;
1918 /* Increment LWP's suspend count. */
1921 lwp_suspended_inc (struct lwp_info
*lwp
)
1925 if (debug_threads
&& lwp
->suspended
> 4)
1927 struct thread_info
*thread
= get_lwp_thread (lwp
);
1929 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1930 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1934 /* Decrement LWP's suspend count. */
1937 lwp_suspended_decr (struct lwp_info
*lwp
)
1941 if (lwp
->suspended
< 0)
1943 struct thread_info
*thread
= get_lwp_thread (lwp
);
1945 internal_error (__FILE__
, __LINE__
,
1946 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1951 /* This function should only be called if the LWP got a SIGTRAP.
1953 Handle any tracepoint steps or hits. Return true if a tracepoint
1954 event was handled, 0 otherwise. */
1957 handle_tracepoints (struct lwp_info
*lwp
)
1959 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1960 int tpoint_related_event
= 0;
1962 gdb_assert (lwp
->suspended
== 0);
1964 /* If this tracepoint hit causes a tracing stop, we'll immediately
1965 uninsert tracepoints. To do this, we temporarily pause all
1966 threads, unpatch away, and then unpause threads. We need to make
1967 sure the unpausing doesn't resume LWP too. */
1968 lwp_suspended_inc (lwp
);
1970 /* And we need to be sure that any all-threads-stopping doesn't try
1971 to move threads out of the jump pads, as it could deadlock the
1972 inferior (LWP could be in the jump pad, maybe even holding the
1975 /* Do any necessary step collect actions. */
1976 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1978 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1980 /* See if we just hit a tracepoint and do its main collect
1982 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1984 lwp_suspended_decr (lwp
);
1986 gdb_assert (lwp
->suspended
== 0);
1987 gdb_assert (!stabilizing_threads
1988 || (lwp
->collecting_fast_tracepoint
1989 != fast_tpoint_collect_result::not_collecting
));
1991 if (tpoint_related_event
)
1994 debug_printf ("got a tracepoint event\n");
2001 /* Convenience wrapper. Returns information about LWP's fast tracepoint
2002 collection status. */
2004 static fast_tpoint_collect_result
2005 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
2006 struct fast_tpoint_collect_status
*status
)
2008 CORE_ADDR thread_area
;
2009 struct thread_info
*thread
= get_lwp_thread (lwp
);
2011 if (the_low_target
.get_thread_area
== NULL
)
2012 return fast_tpoint_collect_result::not_collecting
;
2014 /* Get the thread area address. This is used to recognize which
2015 thread is which when tracing with the in-process agent library.
2016 We don't read anything from the address, and treat it as opaque;
2017 it's the address itself that we assume is unique per-thread. */
2018 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
2019 return fast_tpoint_collect_result::not_collecting
;
2021 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
2025 linux_process_target::maybe_move_out_of_jump_pad (lwp_info
*lwp
, int *wstat
)
2027 struct thread_info
*saved_thread
;
2029 saved_thread
= current_thread
;
2030 current_thread
= get_lwp_thread (lwp
);
2033 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
2034 && supports_fast_tracepoints ()
2035 && agent_loaded_p ())
2037 struct fast_tpoint_collect_status status
;
2040 debug_printf ("Checking whether LWP %ld needs to move out of the "
2042 lwpid_of (current_thread
));
2044 fast_tpoint_collect_result r
2045 = linux_fast_tracepoint_collecting (lwp
, &status
);
2048 || (WSTOPSIG (*wstat
) != SIGILL
2049 && WSTOPSIG (*wstat
) != SIGFPE
2050 && WSTOPSIG (*wstat
) != SIGSEGV
2051 && WSTOPSIG (*wstat
) != SIGBUS
))
2053 lwp
->collecting_fast_tracepoint
= r
;
2055 if (r
!= fast_tpoint_collect_result::not_collecting
)
2057 if (r
== fast_tpoint_collect_result::before_insn
2058 && lwp
->exit_jump_pad_bkpt
== NULL
)
2060 /* Haven't executed the original instruction yet.
2061 Set breakpoint there, and wait till it's hit,
2062 then single-step until exiting the jump pad. */
2063 lwp
->exit_jump_pad_bkpt
2064 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2068 debug_printf ("Checking whether LWP %ld needs to move out of "
2069 "the jump pad...it does\n",
2070 lwpid_of (current_thread
));
2071 current_thread
= saved_thread
;
2078 /* If we get a synchronous signal while collecting, *and*
2079 while executing the (relocated) original instruction,
2080 reset the PC to point at the tpoint address, before
2081 reporting to GDB. Otherwise, it's an IPA lib bug: just
2082 report the signal to GDB, and pray for the best. */
2084 lwp
->collecting_fast_tracepoint
2085 = fast_tpoint_collect_result::not_collecting
;
2087 if (r
!= fast_tpoint_collect_result::not_collecting
2088 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2089 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2092 struct regcache
*regcache
;
2094 /* The si_addr on a few signals references the address
2095 of the faulting instruction. Adjust that as
2097 if ((WSTOPSIG (*wstat
) == SIGILL
2098 || WSTOPSIG (*wstat
) == SIGFPE
2099 || WSTOPSIG (*wstat
) == SIGBUS
2100 || WSTOPSIG (*wstat
) == SIGSEGV
)
2101 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2102 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2103 /* Final check just to make sure we don't clobber
2104 the siginfo of non-kernel-sent signals. */
2105 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2107 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2108 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2109 (PTRACE_TYPE_ARG3
) 0, &info
);
2112 regcache
= get_thread_regcache (current_thread
, 1);
2113 low_set_pc (regcache
, status
.tpoint_addr
);
2114 lwp
->stop_pc
= status
.tpoint_addr
;
2116 /* Cancel any fast tracepoint lock this thread was
2118 force_unlock_trace_buffer ();
2121 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2124 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2125 "stopping all threads momentarily.\n");
2127 stop_all_lwps (1, lwp
);
2129 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2130 lwp
->exit_jump_pad_bkpt
= NULL
;
2132 unstop_all_lwps (1, lwp
);
2134 gdb_assert (lwp
->suspended
>= 0);
2140 debug_printf ("Checking whether LWP %ld needs to move out of the "
2142 lwpid_of (current_thread
));
2144 current_thread
= saved_thread
;
2148 /* Enqueue one signal in the "signals to report later when out of the
2152 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2154 struct pending_signals
*p_sig
;
2155 struct thread_info
*thread
= get_lwp_thread (lwp
);
2158 debug_printf ("Deferring signal %d for LWP %ld.\n",
2159 WSTOPSIG (*wstat
), lwpid_of (thread
));
2163 struct pending_signals
*sig
;
2165 for (sig
= lwp
->pending_signals_to_report
;
2168 debug_printf (" Already queued %d\n",
2171 debug_printf (" (no more currently queued signals)\n");
2174 /* Don't enqueue non-RT signals if they are already in the deferred
2175 queue. (SIGSTOP being the easiest signal to see ending up here
2177 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2179 struct pending_signals
*sig
;
2181 for (sig
= lwp
->pending_signals_to_report
;
2185 if (sig
->signal
== WSTOPSIG (*wstat
))
2188 debug_printf ("Not requeuing already queued non-RT signal %d"
2197 p_sig
= XCNEW (struct pending_signals
);
2198 p_sig
->prev
= lwp
->pending_signals_to_report
;
2199 p_sig
->signal
= WSTOPSIG (*wstat
);
2201 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2204 lwp
->pending_signals_to_report
= p_sig
;
2207 /* Dequeue one signal from the "signals to report later when out of
2208 the jump pad" list. */
2211 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2213 struct thread_info
*thread
= get_lwp_thread (lwp
);
2215 if (lwp
->pending_signals_to_report
!= NULL
)
2217 struct pending_signals
**p_sig
;
2219 p_sig
= &lwp
->pending_signals_to_report
;
2220 while ((*p_sig
)->prev
!= NULL
)
2221 p_sig
= &(*p_sig
)->prev
;
2223 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2224 if ((*p_sig
)->info
.si_signo
!= 0)
2225 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2231 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2232 WSTOPSIG (*wstat
), lwpid_of (thread
));
2236 struct pending_signals
*sig
;
2238 for (sig
= lwp
->pending_signals_to_report
;
2241 debug_printf (" Still queued %d\n",
2244 debug_printf (" (no more queued signals)\n");
2254 linux_process_target::check_stopped_by_watchpoint (lwp_info
*child
)
2256 struct thread_info
*saved_thread
= current_thread
;
2257 current_thread
= get_lwp_thread (child
);
2259 if (low_stopped_by_watchpoint ())
2261 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2262 child
->stopped_data_address
= low_stopped_data_address ();
2265 current_thread
= saved_thread
;
2267 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2271 linux_process_target::low_stopped_by_watchpoint ()
2277 linux_process_target::low_stopped_data_address ()
2282 /* Return the ptrace options that we want to try to enable. */
2285 linux_low_ptrace_options (int attached
)
2287 client_state
&cs
= get_client_state ();
2291 options
|= PTRACE_O_EXITKILL
;
2293 if (cs
.report_fork_events
)
2294 options
|= PTRACE_O_TRACEFORK
;
2296 if (cs
.report_vfork_events
)
2297 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2299 if (cs
.report_exec_events
)
2300 options
|= PTRACE_O_TRACEEXEC
;
2302 options
|= PTRACE_O_TRACESYSGOOD
;
2308 linux_process_target::filter_event (int lwpid
, int wstat
)
2310 client_state
&cs
= get_client_state ();
2311 struct lwp_info
*child
;
2312 struct thread_info
*thread
;
2313 int have_stop_pc
= 0;
2315 child
= find_lwp_pid (ptid_t (lwpid
));
2317 /* Check for stop events reported by a process we didn't already
2318 know about - anything not already in our LWP list.
2320 If we're expecting to receive stopped processes after
2321 fork, vfork, and clone events, then we'll just add the
2322 new one to our list and go back to waiting for the event
2323 to be reported - the stopped process might be returned
2324 from waitpid before or after the event is.
2326 But note the case of a non-leader thread exec'ing after the
2327 leader having exited, and gone from our lists (because
2328 check_zombie_leaders deleted it). The non-leader thread
2329 changes its tid to the tgid. */
2331 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2332 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2336 /* A multi-thread exec after we had seen the leader exiting. */
2339 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2340 "after exec.\n", lwpid
);
2343 child_ptid
= ptid_t (lwpid
, lwpid
, 0);
2344 child
= add_lwp (child_ptid
);
2346 current_thread
= child
->thread
;
2349 /* If we didn't find a process, one of two things presumably happened:
2350 - A process we started and then detached from has exited. Ignore it.
2351 - A process we are controlling has forked and the new child's stop
2352 was reported to us by the kernel. Save its PID. */
2353 if (child
== NULL
&& WIFSTOPPED (wstat
))
2355 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2358 else if (child
== NULL
)
2361 thread
= get_lwp_thread (child
);
2365 child
->last_status
= wstat
;
2367 /* Check if the thread has exited. */
2368 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2371 debug_printf ("LLFE: %d exited.\n", lwpid
);
2373 if (finish_step_over (child
))
2375 /* Unsuspend all other LWPs, and set them back running again. */
2376 unsuspend_all_lwps (child
);
2379 /* If there is at least one more LWP, then the exit signal was
2380 not the end of the debugged application and should be
2381 ignored, unless GDB wants to hear about thread exits. */
2382 if (cs
.report_thread_events
2383 || last_thread_of_process_p (pid_of (thread
)))
2385 /* Since events are serialized to GDB core, and we can't
2386 report this one right now. Leave the status pending for
2387 the next time we're able to report it. */
2388 mark_lwp_dead (child
, wstat
);
2398 gdb_assert (WIFSTOPPED (wstat
));
2400 if (WIFSTOPPED (wstat
))
2402 struct process_info
*proc
;
2404 /* Architecture-specific setup after inferior is running. */
2405 proc
= find_process_pid (pid_of (thread
));
2406 if (proc
->tdesc
== NULL
)
2410 /* This needs to happen after we have attached to the
2411 inferior and it is stopped for the first time, but
2412 before we access any inferior registers. */
2413 arch_setup_thread (thread
);
2417 /* The process is started, but GDBserver will do
2418 architecture-specific setup after the program stops at
2419 the first instruction. */
2420 child
->status_pending_p
= 1;
2421 child
->status_pending
= wstat
;
2427 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2429 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2430 int options
= linux_low_ptrace_options (proc
->attached
);
2432 linux_enable_event_reporting (lwpid
, options
);
2433 child
->must_set_ptrace_flags
= 0;
2436 /* Always update syscall_state, even if it will be filtered later. */
2437 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2439 child
->syscall_state
2440 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2441 ? TARGET_WAITKIND_SYSCALL_RETURN
2442 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2446 /* Almost all other ptrace-stops are known to be outside of system
2447 calls, with further exceptions in handle_extended_wait. */
2448 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2451 /* Be careful to not overwrite stop_pc until save_stop_reason is
2453 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2454 && linux_is_extended_waitstatus (wstat
))
2456 child
->stop_pc
= get_pc (child
);
2457 if (handle_extended_wait (&child
, wstat
))
2459 /* The event has been handled, so just return without
2465 if (linux_wstatus_maybe_breakpoint (wstat
))
2467 if (save_stop_reason (child
))
2472 child
->stop_pc
= get_pc (child
);
2474 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2475 && child
->stop_expected
)
2478 debug_printf ("Expected stop.\n");
2479 child
->stop_expected
= 0;
2481 if (thread
->last_resume_kind
== resume_stop
)
2483 /* We want to report the stop to the core. Treat the
2484 SIGSTOP as a normal event. */
2486 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2487 target_pid_to_str (ptid_of (thread
)));
2489 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2491 /* Stopping threads. We don't want this SIGSTOP to end up
2494 debug_printf ("LLW: SIGSTOP caught for %s "
2495 "while stopping threads.\n",
2496 target_pid_to_str (ptid_of (thread
)));
2501 /* This is a delayed SIGSTOP. Filter out the event. */
2503 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2504 child
->stepping
? "step" : "continue",
2505 target_pid_to_str (ptid_of (thread
)));
2507 resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2512 child
->status_pending_p
= 1;
2513 child
->status_pending
= wstat
;
2517 /* Return true if THREAD is doing hardware single step. */
2520 maybe_hw_step (struct thread_info
*thread
)
2522 if (can_hardware_single_step ())
2526 /* GDBserver must insert single-step breakpoint for software
2528 gdb_assert (has_single_step_breakpoints (thread
));
2534 linux_process_target::resume_stopped_resumed_lwps (thread_info
*thread
)
2536 struct lwp_info
*lp
= get_thread_lwp (thread
);
2540 && !lp
->status_pending_p
2541 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2545 if (thread
->last_resume_kind
== resume_step
)
2546 step
= maybe_hw_step (thread
);
2549 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2550 target_pid_to_str (ptid_of (thread
)),
2551 paddress (lp
->stop_pc
),
2554 resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2559 linux_process_target::wait_for_event_filtered (ptid_t wait_ptid
,
2561 int *wstatp
, int options
)
2563 struct thread_info
*event_thread
;
2564 struct lwp_info
*event_child
, *requested_child
;
2565 sigset_t block_mask
, prev_mask
;
2568 /* N.B. event_thread points to the thread_info struct that contains
2569 event_child. Keep them in sync. */
2570 event_thread
= NULL
;
2572 requested_child
= NULL
;
2574 /* Check for a lwp with a pending status. */
2576 if (filter_ptid
== minus_one_ptid
|| filter_ptid
.is_pid ())
2578 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2580 return status_pending_p_callback (thread
, filter_ptid
);
2583 if (event_thread
!= NULL
)
2584 event_child
= get_thread_lwp (event_thread
);
2585 if (debug_threads
&& event_thread
)
2586 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2588 else if (filter_ptid
!= null_ptid
)
2590 requested_child
= find_lwp_pid (filter_ptid
);
2592 if (stopping_threads
== NOT_STOPPING_THREADS
2593 && requested_child
->status_pending_p
2594 && (requested_child
->collecting_fast_tracepoint
2595 != fast_tpoint_collect_result::not_collecting
))
2597 enqueue_one_deferred_signal (requested_child
,
2598 &requested_child
->status_pending
);
2599 requested_child
->status_pending_p
= 0;
2600 requested_child
->status_pending
= 0;
2601 resume_one_lwp (requested_child
, 0, 0, NULL
);
2604 if (requested_child
->suspended
2605 && requested_child
->status_pending_p
)
2607 internal_error (__FILE__
, __LINE__
,
2608 "requesting an event out of a"
2609 " suspended child?");
2612 if (requested_child
->status_pending_p
)
2614 event_child
= requested_child
;
2615 event_thread
= get_lwp_thread (event_child
);
2619 if (event_child
!= NULL
)
2622 debug_printf ("Got an event from pending child %ld (%04x)\n",
2623 lwpid_of (event_thread
), event_child
->status_pending
);
2624 *wstatp
= event_child
->status_pending
;
2625 event_child
->status_pending_p
= 0;
2626 event_child
->status_pending
= 0;
2627 current_thread
= event_thread
;
2628 return lwpid_of (event_thread
);
2631 /* But if we don't find a pending event, we'll have to wait.
2633 We only enter this loop if no process has a pending wait status.
2634 Thus any action taken in response to a wait status inside this
2635 loop is responding as soon as we detect the status, not after any
2638 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2639 all signals while here. */
2640 sigfillset (&block_mask
);
2641 gdb_sigmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2643 /* Always pull all events out of the kernel. We'll randomly select
2644 an event LWP out of all that have events, to prevent
2646 while (event_child
== NULL
)
2650 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2653 - If the thread group leader exits while other threads in the
2654 thread group still exist, waitpid(TGID, ...) hangs. That
2655 waitpid won't return an exit status until the other threads
2656 in the group are reaped.
2658 - When a non-leader thread execs, that thread just vanishes
2659 without reporting an exit (so we'd hang if we waited for it
2660 explicitly in that case). The exec event is reported to
2663 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2666 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2667 ret
, errno
? safe_strerror (errno
) : "ERRNO-OK");
2673 debug_printf ("LLW: waitpid %ld received %s\n",
2674 (long) ret
, status_to_str (*wstatp
));
2677 /* Filter all events. IOW, leave all events pending. We'll
2678 randomly select an event LWP out of all that have events
2680 filter_event (ret
, *wstatp
);
2681 /* Retry until nothing comes out of waitpid. A single
2682 SIGCHLD can indicate more than one child stopped. */
2686 /* Now that we've pulled all events out of the kernel, resume
2687 LWPs that don't have an interesting event to report. */
2688 if (stopping_threads
== NOT_STOPPING_THREADS
)
2689 for_each_thread ([this] (thread_info
*thread
)
2691 resume_stopped_resumed_lwps (thread
);
2694 /* ... and find an LWP with a status to report to the core, if
2696 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2698 return status_pending_p_callback (thread
, filter_ptid
);
2701 if (event_thread
!= NULL
)
2703 event_child
= get_thread_lwp (event_thread
);
2704 *wstatp
= event_child
->status_pending
;
2705 event_child
->status_pending_p
= 0;
2706 event_child
->status_pending
= 0;
2710 /* Check for zombie thread group leaders. Those can't be reaped
2711 until all other threads in the thread group are. */
2712 check_zombie_leaders ();
2714 auto not_stopped
= [&] (thread_info
*thread
)
2716 return not_stopped_callback (thread
, wait_ptid
);
2719 /* If there are no resumed children left in the set of LWPs we
2720 want to wait for, bail. We can't just block in
2721 waitpid/sigsuspend, because lwps might have been left stopped
2722 in trace-stop state, and we'd be stuck forever waiting for
2723 their status to change (which would only happen if we resumed
2724 them). Even if WNOHANG is set, this return code is preferred
2725 over 0 (below), as it is more detailed. */
2726 if (find_thread (not_stopped
) == NULL
)
2729 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2730 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2734 /* No interesting event to report to the caller. */
2735 if ((options
& WNOHANG
))
2738 debug_printf ("WNOHANG set, no event found\n");
2740 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2744 /* Block until we get an event reported with SIGCHLD. */
2746 debug_printf ("sigsuspend'ing\n");
2748 sigsuspend (&prev_mask
);
2749 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2753 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2755 current_thread
= event_thread
;
2757 return lwpid_of (event_thread
);
2761 linux_process_target::wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2763 return wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2766 /* Select one LWP out of those that have events pending. */
2769 select_event_lwp (struct lwp_info
**orig_lp
)
2771 struct thread_info
*event_thread
= NULL
;
2773 /* In all-stop, give preference to the LWP that is being
2774 single-stepped. There will be at most one, and it's the LWP that
2775 the core is most interested in. If we didn't do this, then we'd
2776 have to handle pending step SIGTRAPs somehow in case the core
2777 later continues the previously-stepped thread, otherwise we'd
2778 report the pending SIGTRAP, and the core, not having stepped the
2779 thread, wouldn't understand what the trap was for, and therefore
2780 would report it to the user as a random signal. */
2783 event_thread
= find_thread ([] (thread_info
*thread
)
2785 lwp_info
*lp
= get_thread_lwp (thread
);
2787 return (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2788 && thread
->last_resume_kind
== resume_step
2789 && lp
->status_pending_p
);
2792 if (event_thread
!= NULL
)
2795 debug_printf ("SEL: Select single-step %s\n",
2796 target_pid_to_str (ptid_of (event_thread
)));
2799 if (event_thread
== NULL
)
2801 /* No single-stepping LWP. Select one at random, out of those
2802 which have had events. */
2804 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2806 lwp_info
*lp
= get_thread_lwp (thread
);
2808 /* Only resumed LWPs that have an event pending. */
2809 return (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2810 && lp
->status_pending_p
);
2814 if (event_thread
!= NULL
)
2816 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2818 /* Switch the event LWP. */
2819 *orig_lp
= event_lp
;
2823 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2827 unsuspend_all_lwps (struct lwp_info
*except
)
2829 for_each_thread ([&] (thread_info
*thread
)
2831 lwp_info
*lwp
= get_thread_lwp (thread
);
2834 lwp_suspended_decr (lwp
);
2838 static bool stuck_in_jump_pad_callback (thread_info
*thread
);
2839 static bool lwp_running (thread_info
*thread
);
2841 /* Stabilize threads (move out of jump pads).
2843 If a thread is midway collecting a fast tracepoint, we need to
2844 finish the collection and move it out of the jump pad before
2845 reporting the signal.
2847 This avoids recursion while collecting (when a signal arrives
2848 midway, and the signal handler itself collects), which would trash
2849 the trace buffer. In case the user set a breakpoint in a signal
2850 handler, this avoids the backtrace showing the jump pad, etc..
2851 Most importantly, there are certain things we can't do safely if
2852 threads are stopped in a jump pad (or in its callee's). For
2855 - starting a new trace run. A thread still collecting the
2856 previous run, could trash the trace buffer when resumed. The trace
2857 buffer control structures would have been reset but the thread had
2858 no way to tell. The thread could even midway memcpy'ing to the
2859 buffer, which would mean that when resumed, it would clobber the
2860 trace buffer that had been set for a new run.
2862 - we can't rewrite/reuse the jump pads for new tracepoints
2863 safely. Say you do tstart while a thread is stopped midway while
2864 collecting. When the thread is later resumed, it finishes the
2865 collection, and returns to the jump pad, to execute the original
2866 instruction that was under the tracepoint jump at the time the
2867 older run had been started. If the jump pad had been rewritten
2868 since for something else in the new run, the thread would now
2869 execute the wrong / random instructions. */
2872 linux_process_target::stabilize_threads ()
2874 thread_info
*thread_stuck
= find_thread (stuck_in_jump_pad_callback
);
2876 if (thread_stuck
!= NULL
)
2879 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2880 lwpid_of (thread_stuck
));
2884 thread_info
*saved_thread
= current_thread
;
2886 stabilizing_threads
= 1;
2889 for_each_thread ([this] (thread_info
*thread
)
2891 move_out_of_jump_pad (thread
);
2894 /* Loop until all are stopped out of the jump pads. */
2895 while (find_thread (lwp_running
) != NULL
)
2897 struct target_waitstatus ourstatus
;
2898 struct lwp_info
*lwp
;
2901 /* Note that we go through the full wait even loop. While
2902 moving threads out of jump pad, we need to be able to step
2903 over internal breakpoints and such. */
2904 wait_1 (minus_one_ptid
, &ourstatus
, 0);
2906 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2908 lwp
= get_thread_lwp (current_thread
);
2911 lwp_suspended_inc (lwp
);
2913 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2914 || current_thread
->last_resume_kind
== resume_stop
)
2916 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2917 enqueue_one_deferred_signal (lwp
, &wstat
);
2922 unsuspend_all_lwps (NULL
);
2924 stabilizing_threads
= 0;
2926 current_thread
= saved_thread
;
2930 thread_stuck
= find_thread (stuck_in_jump_pad_callback
);
2932 if (thread_stuck
!= NULL
)
2933 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2934 lwpid_of (thread_stuck
));
2938 /* Convenience function that is called when the kernel reports an
2939 event that is not passed out to GDB. */
2942 ignore_event (struct target_waitstatus
*ourstatus
)
2944 /* If we got an event, there may still be others, as a single
2945 SIGCHLD can indicate more than one child stopped. This forces
2946 another target_wait call. */
2949 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2954 linux_process_target::filter_exit_event (lwp_info
*event_child
,
2955 target_waitstatus
*ourstatus
)
2957 client_state
&cs
= get_client_state ();
2958 struct thread_info
*thread
= get_lwp_thread (event_child
);
2959 ptid_t ptid
= ptid_of (thread
);
2961 if (!last_thread_of_process_p (pid_of (thread
)))
2963 if (cs
.report_thread_events
)
2964 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
2966 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2968 delete_lwp (event_child
);
2973 /* Returns 1 if GDB is interested in any event_child syscalls. */
2976 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
2978 struct thread_info
*thread
= get_lwp_thread (event_child
);
2979 struct process_info
*proc
= get_thread_process (thread
);
2981 return !proc
->syscalls_to_catch
.empty ();
2984 /* Returns 1 if GDB is interested in the event_child syscall.
2985 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
2988 gdb_catch_this_syscall_p (struct lwp_info
*event_child
)
2991 struct thread_info
*thread
= get_lwp_thread (event_child
);
2992 struct process_info
*proc
= get_thread_process (thread
);
2994 if (proc
->syscalls_to_catch
.empty ())
2997 if (proc
->syscalls_to_catch
[0] == ANY_SYSCALL
)
3000 get_syscall_trapinfo (event_child
, &sysno
);
3002 for (int iter
: proc
->syscalls_to_catch
)
3010 linux_process_target::wait_1 (ptid_t ptid
, target_waitstatus
*ourstatus
,
3013 client_state
&cs
= get_client_state ();
3015 struct lwp_info
*event_child
;
3018 int step_over_finished
;
3019 int bp_explains_trap
;
3020 int maybe_internal_trap
;
3029 debug_printf ("wait_1: [%s]\n", target_pid_to_str (ptid
));
3032 /* Translate generic target options into linux options. */
3034 if (target_options
& TARGET_WNOHANG
)
3037 bp_explains_trap
= 0;
3040 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3042 auto status_pending_p_any
= [&] (thread_info
*thread
)
3044 return status_pending_p_callback (thread
, minus_one_ptid
);
3047 auto not_stopped
= [&] (thread_info
*thread
)
3049 return not_stopped_callback (thread
, minus_one_ptid
);
3052 /* Find a resumed LWP, if any. */
3053 if (find_thread (status_pending_p_any
) != NULL
)
3055 else if (find_thread (not_stopped
) != NULL
)
3060 if (step_over_bkpt
== null_ptid
)
3061 pid
= wait_for_event (ptid
, &w
, options
);
3065 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3066 target_pid_to_str (step_over_bkpt
));
3067 pid
= wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3070 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3072 gdb_assert (target_options
& TARGET_WNOHANG
);
3076 debug_printf ("wait_1 ret = null_ptid, "
3077 "TARGET_WAITKIND_IGNORE\n");
3081 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3088 debug_printf ("wait_1 ret = null_ptid, "
3089 "TARGET_WAITKIND_NO_RESUMED\n");
3093 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3097 event_child
= get_thread_lwp (current_thread
);
3099 /* wait_for_event only returns an exit status for the last
3100 child of a process. Report it. */
3101 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3105 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3106 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3110 debug_printf ("wait_1 ret = %s, exited with "
3112 target_pid_to_str (ptid_of (current_thread
)),
3119 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3120 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3124 debug_printf ("wait_1 ret = %s, terminated with "
3126 target_pid_to_str (ptid_of (current_thread
)),
3132 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3133 return filter_exit_event (event_child
, ourstatus
);
3135 return ptid_of (current_thread
);
3138 /* If step-over executes a breakpoint instruction, in the case of a
3139 hardware single step it means a gdb/gdbserver breakpoint had been
3140 planted on top of a permanent breakpoint, in the case of a software
3141 single step it may just mean that gdbserver hit the reinsert breakpoint.
3142 The PC has been adjusted by save_stop_reason to point at
3143 the breakpoint address.
3144 So in the case of the hardware single step advance the PC manually
3145 past the breakpoint and in the case of software single step advance only
3146 if it's not the single_step_breakpoint we are hitting.
3147 This avoids that a program would keep trapping a permanent breakpoint
3149 if (step_over_bkpt
!= null_ptid
3150 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3151 && (event_child
->stepping
3152 || !single_step_breakpoint_inserted_here (event_child
->stop_pc
)))
3154 int increment_pc
= 0;
3155 int breakpoint_kind
= 0;
3156 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3158 breakpoint_kind
= breakpoint_kind_from_current_state (&stop_pc
);
3159 sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3163 debug_printf ("step-over for %s executed software breakpoint\n",
3164 target_pid_to_str (ptid_of (current_thread
)));
3167 if (increment_pc
!= 0)
3169 struct regcache
*regcache
3170 = get_thread_regcache (current_thread
, 1);
3172 event_child
->stop_pc
+= increment_pc
;
3173 low_set_pc (regcache
, event_child
->stop_pc
);
3175 if (!low_breakpoint_at (event_child
->stop_pc
))
3176 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3180 /* If this event was not handled before, and is not a SIGTRAP, we
3181 report it. SIGILL and SIGSEGV are also treated as traps in case
3182 a breakpoint is inserted at the current PC. If this target does
3183 not support internal breakpoints at all, we also report the
3184 SIGTRAP without further processing; it's of no concern to us. */
3186 = (low_supports_breakpoints ()
3187 && (WSTOPSIG (w
) == SIGTRAP
3188 || ((WSTOPSIG (w
) == SIGILL
3189 || WSTOPSIG (w
) == SIGSEGV
)
3190 && low_breakpoint_at (event_child
->stop_pc
))));
3192 if (maybe_internal_trap
)
3194 /* Handle anything that requires bookkeeping before deciding to
3195 report the event or continue waiting. */
3197 /* First check if we can explain the SIGTRAP with an internal
3198 breakpoint, or if we should possibly report the event to GDB.
3199 Do this before anything that may remove or insert a
3201 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3203 /* We have a SIGTRAP, possibly a step-over dance has just
3204 finished. If so, tweak the state machine accordingly,
3205 reinsert breakpoints and delete any single-step
3207 step_over_finished
= finish_step_over (event_child
);
3209 /* Now invoke the callbacks of any internal breakpoints there. */
3210 check_breakpoints (event_child
->stop_pc
);
3212 /* Handle tracepoint data collecting. This may overflow the
3213 trace buffer, and cause a tracing stop, removing
3215 trace_event
= handle_tracepoints (event_child
);
3217 if (bp_explains_trap
)
3220 debug_printf ("Hit a gdbserver breakpoint.\n");
3225 /* We have some other signal, possibly a step-over dance was in
3226 progress, and it should be cancelled too. */
3227 step_over_finished
= finish_step_over (event_child
);
3230 /* We have all the data we need. Either report the event to GDB, or
3231 resume threads and keep waiting for more. */
3233 /* If we're collecting a fast tracepoint, finish the collection and
3234 move out of the jump pad before delivering a signal. See
3235 linux_stabilize_threads. */
3238 && WSTOPSIG (w
) != SIGTRAP
3239 && supports_fast_tracepoints ()
3240 && agent_loaded_p ())
3243 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3244 "to defer or adjust it.\n",
3245 WSTOPSIG (w
), lwpid_of (current_thread
));
3247 /* Allow debugging the jump pad itself. */
3248 if (current_thread
->last_resume_kind
!= resume_step
3249 && maybe_move_out_of_jump_pad (event_child
, &w
))
3251 enqueue_one_deferred_signal (event_child
, &w
);
3254 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3255 WSTOPSIG (w
), lwpid_of (current_thread
));
3257 resume_one_lwp (event_child
, 0, 0, NULL
);
3261 return ignore_event (ourstatus
);
3265 if (event_child
->collecting_fast_tracepoint
3266 != fast_tpoint_collect_result::not_collecting
)
3269 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3270 "Check if we're already there.\n",
3271 lwpid_of (current_thread
),
3272 (int) event_child
->collecting_fast_tracepoint
);
3276 event_child
->collecting_fast_tracepoint
3277 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3279 if (event_child
->collecting_fast_tracepoint
3280 != fast_tpoint_collect_result::before_insn
)
3282 /* No longer need this breakpoint. */
3283 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3286 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3287 "stopping all threads momentarily.\n");
3289 /* Other running threads could hit this breakpoint.
3290 We don't handle moribund locations like GDB does,
3291 instead we always pause all threads when removing
3292 breakpoints, so that any step-over or
3293 decr_pc_after_break adjustment is always taken
3294 care of while the breakpoint is still
3296 stop_all_lwps (1, event_child
);
3298 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3299 event_child
->exit_jump_pad_bkpt
= NULL
;
3301 unstop_all_lwps (1, event_child
);
3303 gdb_assert (event_child
->suspended
>= 0);
3307 if (event_child
->collecting_fast_tracepoint
3308 == fast_tpoint_collect_result::not_collecting
)
3311 debug_printf ("fast tracepoint finished "
3312 "collecting successfully.\n");
3314 /* We may have a deferred signal to report. */
3315 if (dequeue_one_deferred_signal (event_child
, &w
))
3318 debug_printf ("dequeued one signal.\n");
3323 debug_printf ("no deferred signals.\n");
3325 if (stabilizing_threads
)
3327 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3328 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3332 debug_printf ("wait_1 ret = %s, stopped "
3333 "while stabilizing threads\n",
3334 target_pid_to_str (ptid_of (current_thread
)));
3338 return ptid_of (current_thread
);
3344 /* Check whether GDB would be interested in this event. */
3346 /* Check if GDB is interested in this syscall. */
3348 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3349 && !gdb_catch_this_syscall_p (event_child
))
3353 debug_printf ("Ignored syscall for LWP %ld.\n",
3354 lwpid_of (current_thread
));
3357 resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
3361 return ignore_event (ourstatus
);
3364 /* If GDB is not interested in this signal, don't stop other
3365 threads, and don't report it to GDB. Just resume the inferior
3366 right away. We do this for threading-related signals as well as
3367 any that GDB specifically requested we ignore. But never ignore
3368 SIGSTOP if we sent it ourselves, and do not ignore signals when
3369 stepping - they may require special handling to skip the signal
3370 handler. Also never ignore signals that could be caused by a
3373 && current_thread
->last_resume_kind
!= resume_step
3375 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3376 (current_process ()->priv
->thread_db
!= NULL
3377 && (WSTOPSIG (w
) == __SIGRTMIN
3378 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3381 (cs
.pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3382 && !(WSTOPSIG (w
) == SIGSTOP
3383 && current_thread
->last_resume_kind
== resume_stop
)
3384 && !linux_wstatus_maybe_breakpoint (w
))))
3386 siginfo_t info
, *info_p
;
3389 debug_printf ("Ignored signal %d for LWP %ld.\n",
3390 WSTOPSIG (w
), lwpid_of (current_thread
));
3392 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3393 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3398 if (step_over_finished
)
3400 /* We cancelled this thread's step-over above. We still
3401 need to unsuspend all other LWPs, and set them back
3402 running again while the signal handler runs. */
3403 unsuspend_all_lwps (event_child
);
3405 /* Enqueue the pending signal info so that proceed_all_lwps
3407 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3409 proceed_all_lwps ();
3413 resume_one_lwp (event_child
, event_child
->stepping
,
3414 WSTOPSIG (w
), info_p
);
3420 return ignore_event (ourstatus
);
3423 /* Note that all addresses are always "out of the step range" when
3424 there's no range to begin with. */
3425 in_step_range
= lwp_in_step_range (event_child
);
3427 /* If GDB wanted this thread to single step, and the thread is out
3428 of the step range, we always want to report the SIGTRAP, and let
3429 GDB handle it. Watchpoints should always be reported. So should
3430 signals we can't explain. A SIGTRAP we can't explain could be a
3431 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3432 do, we're be able to handle GDB breakpoints on top of internal
3433 breakpoints, by handling the internal breakpoint and still
3434 reporting the event to GDB. If we don't, we're out of luck, GDB
3435 won't see the breakpoint hit. If we see a single-step event but
3436 the thread should be continuing, don't pass the trap to gdb.
3437 That indicates that we had previously finished a single-step but
3438 left the single-step pending -- see
3439 complete_ongoing_step_over. */
3440 report_to_gdb
= (!maybe_internal_trap
3441 || (current_thread
->last_resume_kind
== resume_step
3443 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3445 && !bp_explains_trap
3447 && !step_over_finished
3448 && !(current_thread
->last_resume_kind
== resume_continue
3449 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3450 || (gdb_breakpoint_here (event_child
->stop_pc
)
3451 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3452 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3453 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3455 run_breakpoint_commands (event_child
->stop_pc
);
3457 /* We found no reason GDB would want us to stop. We either hit one
3458 of our own breakpoints, or finished an internal step GDB
3459 shouldn't know about. */
3464 if (bp_explains_trap
)
3465 debug_printf ("Hit a gdbserver breakpoint.\n");
3466 if (step_over_finished
)
3467 debug_printf ("Step-over finished.\n");
3469 debug_printf ("Tracepoint event.\n");
3470 if (lwp_in_step_range (event_child
))
3471 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3472 paddress (event_child
->stop_pc
),
3473 paddress (event_child
->step_range_start
),
3474 paddress (event_child
->step_range_end
));
3477 /* We're not reporting this breakpoint to GDB, so apply the
3478 decr_pc_after_break adjustment to the inferior's regcache
3481 if (low_supports_breakpoints ())
3483 struct regcache
*regcache
3484 = get_thread_regcache (current_thread
, 1);
3485 low_set_pc (regcache
, event_child
->stop_pc
);
3488 if (step_over_finished
)
3490 /* If we have finished stepping over a breakpoint, we've
3491 stopped and suspended all LWPs momentarily except the
3492 stepping one. This is where we resume them all again.
3493 We're going to keep waiting, so use proceed, which
3494 handles stepping over the next breakpoint. */
3495 unsuspend_all_lwps (event_child
);
3499 /* Remove the single-step breakpoints if any. Note that
3500 there isn't single-step breakpoint if we finished stepping
3502 if (supports_software_single_step ()
3503 && has_single_step_breakpoints (current_thread
))
3505 stop_all_lwps (0, event_child
);
3506 delete_single_step_breakpoints (current_thread
);
3507 unstop_all_lwps (0, event_child
);
3512 debug_printf ("proceeding all threads.\n");
3513 proceed_all_lwps ();
3518 return ignore_event (ourstatus
);
3523 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3526 = target_waitstatus_to_string (&event_child
->waitstatus
);
3528 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3529 lwpid_of (get_lwp_thread (event_child
)), str
.c_str ());
3531 if (current_thread
->last_resume_kind
== resume_step
)
3533 if (event_child
->step_range_start
== event_child
->step_range_end
)
3534 debug_printf ("GDB wanted to single-step, reporting event.\n");
3535 else if (!lwp_in_step_range (event_child
))
3536 debug_printf ("Out of step range, reporting event.\n");
3538 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3539 debug_printf ("Stopped by watchpoint.\n");
3540 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3541 debug_printf ("Stopped by GDB breakpoint.\n");
3543 debug_printf ("Hit a non-gdbserver trap event.\n");
3546 /* Alright, we're going to report a stop. */
3548 /* Remove single-step breakpoints. */
3549 if (supports_software_single_step ())
3551 /* Remove single-step breakpoints or not. It it is true, stop all
3552 lwps, so that other threads won't hit the breakpoint in the
3554 int remove_single_step_breakpoints_p
= 0;
3558 remove_single_step_breakpoints_p
3559 = has_single_step_breakpoints (current_thread
);
3563 /* In all-stop, a stop reply cancels all previous resume
3564 requests. Delete all single-step breakpoints. */
3566 find_thread ([&] (thread_info
*thread
) {
3567 if (has_single_step_breakpoints (thread
))
3569 remove_single_step_breakpoints_p
= 1;
3577 if (remove_single_step_breakpoints_p
)
3579 /* If we remove single-step breakpoints from memory, stop all lwps,
3580 so that other threads won't hit the breakpoint in the staled
3582 stop_all_lwps (0, event_child
);
3586 gdb_assert (has_single_step_breakpoints (current_thread
));
3587 delete_single_step_breakpoints (current_thread
);
3591 for_each_thread ([] (thread_info
*thread
){
3592 if (has_single_step_breakpoints (thread
))
3593 delete_single_step_breakpoints (thread
);
3597 unstop_all_lwps (0, event_child
);
3601 if (!stabilizing_threads
)
3603 /* In all-stop, stop all threads. */
3605 stop_all_lwps (0, NULL
);
3607 if (step_over_finished
)
3611 /* If we were doing a step-over, all other threads but
3612 the stepping one had been paused in start_step_over,
3613 with their suspend counts incremented. We don't want
3614 to do a full unstop/unpause, because we're in
3615 all-stop mode (so we want threads stopped), but we
3616 still need to unsuspend the other threads, to
3617 decrement their `suspended' count back. */
3618 unsuspend_all_lwps (event_child
);
3622 /* If we just finished a step-over, then all threads had
3623 been momentarily paused. In all-stop, that's fine,
3624 we want threads stopped by now anyway. In non-stop,
3625 we need to re-resume threads that GDB wanted to be
3627 unstop_all_lwps (1, event_child
);
3631 /* If we're not waiting for a specific LWP, choose an event LWP
3632 from among those that have had events. Giving equal priority
3633 to all LWPs that have had events helps prevent
3635 if (ptid
== minus_one_ptid
)
3637 event_child
->status_pending_p
= 1;
3638 event_child
->status_pending
= w
;
3640 select_event_lwp (&event_child
);
3642 /* current_thread and event_child must stay in sync. */
3643 current_thread
= get_lwp_thread (event_child
);
3645 event_child
->status_pending_p
= 0;
3646 w
= event_child
->status_pending
;
3650 /* Stabilize threads (move out of jump pads). */
3652 target_stabilize_threads ();
3656 /* If we just finished a step-over, then all threads had been
3657 momentarily paused. In all-stop, that's fine, we want
3658 threads stopped by now anyway. In non-stop, we need to
3659 re-resume threads that GDB wanted to be running. */
3660 if (step_over_finished
)
3661 unstop_all_lwps (1, event_child
);
3664 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3666 /* If the reported event is an exit, fork, vfork or exec, let
3669 /* Break the unreported fork relationship chain. */
3670 if (event_child
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
3671 || event_child
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
)
3673 event_child
->fork_relative
->fork_relative
= NULL
;
3674 event_child
->fork_relative
= NULL
;
3677 *ourstatus
= event_child
->waitstatus
;
3678 /* Clear the event lwp's waitstatus since we handled it already. */
3679 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3682 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3684 /* Now that we've selected our final event LWP, un-adjust its PC if
3685 it was a software breakpoint, and the client doesn't know we can
3686 adjust the breakpoint ourselves. */
3687 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3688 && !cs
.swbreak_feature
)
3690 int decr_pc
= low_decr_pc_after_break ();
3694 struct regcache
*regcache
3695 = get_thread_regcache (current_thread
, 1);
3696 low_set_pc (regcache
, event_child
->stop_pc
+ decr_pc
);
3700 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3702 get_syscall_trapinfo (event_child
,
3703 &ourstatus
->value
.syscall_number
);
3704 ourstatus
->kind
= event_child
->syscall_state
;
3706 else if (current_thread
->last_resume_kind
== resume_stop
3707 && WSTOPSIG (w
) == SIGSTOP
)
3709 /* A thread that has been requested to stop by GDB with vCont;t,
3710 and it stopped cleanly, so report as SIG0. The use of
3711 SIGSTOP is an implementation detail. */
3712 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3714 else if (current_thread
->last_resume_kind
== resume_stop
3715 && WSTOPSIG (w
) != SIGSTOP
)
3717 /* A thread that has been requested to stop by GDB with vCont;t,
3718 but, it stopped for other reasons. */
3719 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3721 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3723 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3726 gdb_assert (step_over_bkpt
== null_ptid
);
3730 debug_printf ("wait_1 ret = %s, %d, %d\n",
3731 target_pid_to_str (ptid_of (current_thread
)),
3732 ourstatus
->kind
, ourstatus
->value
.sig
);
3736 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3737 return filter_exit_event (event_child
, ourstatus
);
3739 return ptid_of (current_thread
);
3742 /* Get rid of any pending event in the pipe. */
3744 async_file_flush (void)
3750 ret
= read (linux_event_pipe
[0], &buf
, 1);
3751 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3754 /* Put something in the pipe, so the event loop wakes up. */
3756 async_file_mark (void)
3760 async_file_flush ();
3763 ret
= write (linux_event_pipe
[1], "+", 1);
3764 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3766 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3767 be awakened anyway. */
3771 linux_process_target::wait (ptid_t ptid
,
3772 target_waitstatus
*ourstatus
,
3777 /* Flush the async file first. */
3778 if (target_is_async_p ())
3779 async_file_flush ();
3783 event_ptid
= wait_1 (ptid
, ourstatus
, target_options
);
3785 while ((target_options
& TARGET_WNOHANG
) == 0
3786 && event_ptid
== null_ptid
3787 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3789 /* If at least one stop was reported, there may be more. A single
3790 SIGCHLD can signal more than one child stop. */
3791 if (target_is_async_p ()
3792 && (target_options
& TARGET_WNOHANG
) != 0
3793 && event_ptid
!= null_ptid
)
3799 /* Send a signal to an LWP. */
3802 kill_lwp (unsigned long lwpid
, int signo
)
3807 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3808 if (errno
== ENOSYS
)
3810 /* If tkill fails, then we are not using nptl threads, a
3811 configuration we no longer support. */
3812 perror_with_name (("tkill"));
3818 linux_stop_lwp (struct lwp_info
*lwp
)
3824 send_sigstop (struct lwp_info
*lwp
)
3828 pid
= lwpid_of (get_lwp_thread (lwp
));
3830 /* If we already have a pending stop signal for this process, don't
3832 if (lwp
->stop_expected
)
3835 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3841 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3843 lwp
->stop_expected
= 1;
3844 kill_lwp (pid
, SIGSTOP
);
3848 send_sigstop (thread_info
*thread
, lwp_info
*except
)
3850 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3852 /* Ignore EXCEPT. */
3862 /* Increment the suspend count of an LWP, and stop it, if not stopped
3865 suspend_and_send_sigstop (thread_info
*thread
, lwp_info
*except
)
3867 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3869 /* Ignore EXCEPT. */
3873 lwp_suspended_inc (lwp
);
3875 send_sigstop (thread
, except
);
3879 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3881 /* Store the exit status for later. */
3882 lwp
->status_pending_p
= 1;
3883 lwp
->status_pending
= wstat
;
3885 /* Store in waitstatus as well, as there's nothing else to process
3887 if (WIFEXITED (wstat
))
3889 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3890 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3892 else if (WIFSIGNALED (wstat
))
3894 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3895 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3898 /* Prevent trying to stop it. */
3901 /* No further stops are expected from a dead lwp. */
3902 lwp
->stop_expected
= 0;
3905 /* Return true if LWP has exited already, and has a pending exit event
3906 to report to GDB. */
3909 lwp_is_marked_dead (struct lwp_info
*lwp
)
3911 return (lwp
->status_pending_p
3912 && (WIFEXITED (lwp
->status_pending
)
3913 || WIFSIGNALED (lwp
->status_pending
)));
3917 linux_process_target::wait_for_sigstop ()
3919 struct thread_info
*saved_thread
;
3924 saved_thread
= current_thread
;
3925 if (saved_thread
!= NULL
)
3926 saved_tid
= saved_thread
->id
;
3928 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3931 debug_printf ("wait_for_sigstop: pulling events\n");
3933 /* Passing NULL_PTID as filter indicates we want all events to be
3934 left pending. Eventually this returns when there are no
3935 unwaited-for children left. */
3936 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
, __WALL
);
3937 gdb_assert (ret
== -1);
3939 if (saved_thread
== NULL
|| mythread_alive (saved_tid
))
3940 current_thread
= saved_thread
;
3944 debug_printf ("Previously current thread died.\n");
3946 /* We can't change the current inferior behind GDB's back,
3947 otherwise, a subsequent command may apply to the wrong
3949 current_thread
= NULL
;
3953 /* Returns true if THREAD is stopped in a jump pad, and we can't
3954 move it out, because we need to report the stop event to GDB. For
3955 example, if the user puts a breakpoint in the jump pad, it's
3956 because she wants to debug it. */
3959 stuck_in_jump_pad_callback (thread_info
*thread
)
3961 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3963 if (lwp
->suspended
!= 0)
3965 internal_error (__FILE__
, __LINE__
,
3966 "LWP %ld is suspended, suspended=%d\n",
3967 lwpid_of (thread
), lwp
->suspended
);
3969 gdb_assert (lwp
->stopped
);
3971 /* Allow debugging the jump pad, gdb_collect, etc.. */
3972 return (supports_fast_tracepoints ()
3973 && agent_loaded_p ()
3974 && (gdb_breakpoint_here (lwp
->stop_pc
)
3975 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3976 || thread
->last_resume_kind
== resume_step
)
3977 && (linux_fast_tracepoint_collecting (lwp
, NULL
)
3978 != fast_tpoint_collect_result::not_collecting
));
3982 linux_process_target::move_out_of_jump_pad (thread_info
*thread
)
3984 struct thread_info
*saved_thread
;
3985 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3988 if (lwp
->suspended
!= 0)
3990 internal_error (__FILE__
, __LINE__
,
3991 "LWP %ld is suspended, suspended=%d\n",
3992 lwpid_of (thread
), lwp
->suspended
);
3994 gdb_assert (lwp
->stopped
);
3996 /* For gdb_breakpoint_here. */
3997 saved_thread
= current_thread
;
3998 current_thread
= thread
;
4000 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
4002 /* Allow debugging the jump pad, gdb_collect, etc. */
4003 if (!gdb_breakpoint_here (lwp
->stop_pc
)
4004 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
4005 && thread
->last_resume_kind
!= resume_step
4006 && maybe_move_out_of_jump_pad (lwp
, wstat
))
4009 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
4014 lwp
->status_pending_p
= 0;
4015 enqueue_one_deferred_signal (lwp
, wstat
);
4018 debug_printf ("Signal %d for LWP %ld deferred "
4020 WSTOPSIG (*wstat
), lwpid_of (thread
));
4023 resume_one_lwp (lwp
, 0, 0, NULL
);
4026 lwp_suspended_inc (lwp
);
4028 current_thread
= saved_thread
;
4032 lwp_running (thread_info
*thread
)
4034 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4036 if (lwp_is_marked_dead (lwp
))
4039 return !lwp
->stopped
;
4043 linux_process_target::stop_all_lwps (int suspend
, lwp_info
*except
)
4045 /* Should not be called recursively. */
4046 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
4051 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4052 suspend
? "stop-and-suspend" : "stop",
4054 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
4058 stopping_threads
= (suspend
4059 ? STOPPING_AND_SUSPENDING_THREADS
4060 : STOPPING_THREADS
);
4063 for_each_thread ([&] (thread_info
*thread
)
4065 suspend_and_send_sigstop (thread
, except
);
4068 for_each_thread ([&] (thread_info
*thread
)
4070 send_sigstop (thread
, except
);
4073 wait_for_sigstop ();
4074 stopping_threads
= NOT_STOPPING_THREADS
;
4078 debug_printf ("stop_all_lwps done, setting stopping_threads "
4079 "back to !stopping\n");
4084 /* Enqueue one signal in the chain of signals which need to be
4085 delivered to this process on next resume. */
4088 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4090 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4092 p_sig
->prev
= lwp
->pending_signals
;
4093 p_sig
->signal
= signal
;
4095 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4097 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4098 lwp
->pending_signals
= p_sig
;
4102 linux_process_target::install_software_single_step_breakpoints (lwp_info
*lwp
)
4104 struct thread_info
*thread
= get_lwp_thread (lwp
);
4105 struct regcache
*regcache
= get_thread_regcache (thread
, 1);
4107 scoped_restore save_current_thread
= make_scoped_restore (¤t_thread
);
4109 current_thread
= thread
;
4110 std::vector
<CORE_ADDR
> next_pcs
= low_get_next_pcs (regcache
);
4112 for (CORE_ADDR pc
: next_pcs
)
4113 set_single_step_breakpoint (pc
, current_ptid
);
4117 linux_process_target::single_step (lwp_info
* lwp
)
4121 if (can_hardware_single_step ())
4125 else if (supports_software_single_step ())
4127 install_software_single_step_breakpoints (lwp
);
4133 debug_printf ("stepping is not implemented on this target");
4139 /* The signal can be delivered to the inferior if we are not trying to
4140 finish a fast tracepoint collect. Since signal can be delivered in
4141 the step-over, the program may go to signal handler and trap again
4142 after return from the signal handler. We can live with the spurious
4146 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
4148 return (lwp
->collecting_fast_tracepoint
4149 == fast_tpoint_collect_result::not_collecting
);
4153 linux_process_target::resume_one_lwp_throw (lwp_info
*lwp
, int step
,
4154 int signal
, siginfo_t
*info
)
4156 struct thread_info
*thread
= get_lwp_thread (lwp
);
4157 struct thread_info
*saved_thread
;
4159 struct process_info
*proc
= get_thread_process (thread
);
4161 /* Note that target description may not be initialised
4162 (proc->tdesc == NULL) at this point because the program hasn't
4163 stopped at the first instruction yet. It means GDBserver skips
4164 the extra traps from the wrapper program (see option --wrapper).
4165 Code in this function that requires register access should be
4166 guarded by proc->tdesc == NULL or something else. */
4168 if (lwp
->stopped
== 0)
4171 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4173 fast_tpoint_collect_result fast_tp_collecting
4174 = lwp
->collecting_fast_tracepoint
;
4176 gdb_assert (!stabilizing_threads
4177 || (fast_tp_collecting
4178 != fast_tpoint_collect_result::not_collecting
));
4180 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4181 user used the "jump" command, or "set $pc = foo"). */
4182 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4184 /* Collecting 'while-stepping' actions doesn't make sense
4186 release_while_stepping_state_list (thread
);
4189 /* If we have pending signals or status, and a new signal, enqueue the
4190 signal. Also enqueue the signal if it can't be delivered to the
4191 inferior right now. */
4193 && (lwp
->status_pending_p
4194 || lwp
->pending_signals
!= NULL
4195 || !lwp_signal_can_be_delivered (lwp
)))
4197 enqueue_pending_signal (lwp
, signal
, info
);
4199 /* Postpone any pending signal. It was enqueued above. */
4203 if (lwp
->status_pending_p
)
4206 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4207 " has pending status\n",
4208 lwpid_of (thread
), step
? "step" : "continue",
4209 lwp
->stop_expected
? "expected" : "not expected");
4213 saved_thread
= current_thread
;
4214 current_thread
= thread
;
4216 /* This bit needs some thinking about. If we get a signal that
4217 we must report while a single-step reinsert is still pending,
4218 we often end up resuming the thread. It might be better to
4219 (ew) allow a stack of pending events; then we could be sure that
4220 the reinsert happened right away and not lose any signals.
4222 Making this stack would also shrink the window in which breakpoints are
4223 uninserted (see comment in linux_wait_for_lwp) but not enough for
4224 complete correctness, so it won't solve that problem. It may be
4225 worthwhile just to solve this one, however. */
4226 if (lwp
->bp_reinsert
!= 0)
4229 debug_printf (" pending reinsert at 0x%s\n",
4230 paddress (lwp
->bp_reinsert
));
4232 if (can_hardware_single_step ())
4234 if (fast_tp_collecting
== fast_tpoint_collect_result::not_collecting
)
4237 warning ("BAD - reinserting but not stepping.");
4239 warning ("BAD - reinserting and suspended(%d).",
4244 step
= maybe_hw_step (thread
);
4247 if (fast_tp_collecting
== fast_tpoint_collect_result::before_insn
)
4250 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4251 " (exit-jump-pad-bkpt)\n",
4254 else if (fast_tp_collecting
== fast_tpoint_collect_result::at_insn
)
4257 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4258 " single-stepping\n",
4261 if (can_hardware_single_step ())
4265 internal_error (__FILE__
, __LINE__
,
4266 "moving out of jump pad single-stepping"
4267 " not implemented on this target");
4271 /* If we have while-stepping actions in this thread set it stepping.
4272 If we have a signal to deliver, it may or may not be set to
4273 SIG_IGN, we don't know. Assume so, and allow collecting
4274 while-stepping into a signal handler. A possible smart thing to
4275 do would be to set an internal breakpoint at the signal return
4276 address, continue, and carry on catching this while-stepping
4277 action only when that breakpoint is hit. A future
4279 if (thread
->while_stepping
!= NULL
)
4282 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4285 step
= single_step (lwp
);
4288 if (proc
->tdesc
!= NULL
&& low_supports_breakpoints ())
4290 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4292 lwp
->stop_pc
= low_get_pc (regcache
);
4296 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4297 (long) lwp
->stop_pc
);
4301 /* If we have pending signals, consume one if it can be delivered to
4303 if (lwp
->pending_signals
!= NULL
&& lwp_signal_can_be_delivered (lwp
))
4305 struct pending_signals
**p_sig
;
4307 p_sig
= &lwp
->pending_signals
;
4308 while ((*p_sig
)->prev
!= NULL
)
4309 p_sig
= &(*p_sig
)->prev
;
4311 signal
= (*p_sig
)->signal
;
4312 if ((*p_sig
)->info
.si_signo
!= 0)
4313 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4321 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4322 lwpid_of (thread
), step
? "step" : "continue", signal
,
4323 lwp
->stop_expected
? "expected" : "not expected");
4325 if (the_low_target
.prepare_to_resume
!= NULL
)
4326 the_low_target
.prepare_to_resume (lwp
);
4328 regcache_invalidate_thread (thread
);
4330 lwp
->stepping
= step
;
4332 ptrace_request
= PTRACE_SINGLESTEP
;
4333 else if (gdb_catching_syscalls_p (lwp
))
4334 ptrace_request
= PTRACE_SYSCALL
;
4336 ptrace_request
= PTRACE_CONT
;
4337 ptrace (ptrace_request
,
4339 (PTRACE_TYPE_ARG3
) 0,
4340 /* Coerce to a uintptr_t first to avoid potential gcc warning
4341 of coercing an 8 byte integer to a 4 byte pointer. */
4342 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4344 current_thread
= saved_thread
;
4346 perror_with_name ("resuming thread");
4348 /* Successfully resumed. Clear state that no longer makes sense,
4349 and mark the LWP as running. Must not do this before resuming
4350 otherwise if that fails other code will be confused. E.g., we'd
4351 later try to stop the LWP and hang forever waiting for a stop
4352 status. Note that we must not throw after this is cleared,
4353 otherwise handle_zombie_lwp_error would get confused. */
4355 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4358 /* Called when we try to resume a stopped LWP and that errors out. If
4359 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4360 or about to become), discard the error, clear any pending status
4361 the LWP may have, and return true (we'll collect the exit status
4362 soon enough). Otherwise, return false. */
4365 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4367 struct thread_info
*thread
= get_lwp_thread (lp
);
4369 /* If we get an error after resuming the LWP successfully, we'd
4370 confuse !T state for the LWP being gone. */
4371 gdb_assert (lp
->stopped
);
4373 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4374 because even if ptrace failed with ESRCH, the tracee may be "not
4375 yet fully dead", but already refusing ptrace requests. In that
4376 case the tracee has 'R (Running)' state for a little bit
4377 (observed in Linux 3.18). See also the note on ESRCH in the
4378 ptrace(2) man page. Instead, check whether the LWP has any state
4379 other than ptrace-stopped. */
4381 /* Don't assume anything if /proc/PID/status can't be read. */
4382 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4384 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4385 lp
->status_pending_p
= 0;
4392 linux_process_target::resume_one_lwp (lwp_info
*lwp
, int step
, int signal
,
4397 resume_one_lwp_throw (lwp
, step
, signal
, info
);
4399 catch (const gdb_exception_error
&ex
)
4401 if (!check_ptrace_stopped_lwp_gone (lwp
))
4406 /* This function is called once per thread via for_each_thread.
4407 We look up which resume request applies to THREAD and mark it with a
4408 pointer to the appropriate resume request.
4410 This algorithm is O(threads * resume elements), but resume elements
4411 is small (and will remain small at least until GDB supports thread
4415 linux_set_resume_request (thread_info
*thread
, thread_resume
*resume
, size_t n
)
4417 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4419 for (int ndx
= 0; ndx
< n
; ndx
++)
4421 ptid_t ptid
= resume
[ndx
].thread
;
4422 if (ptid
== minus_one_ptid
4423 || ptid
== thread
->id
4424 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4426 || (ptid
.pid () == pid_of (thread
)
4428 || ptid
.lwp () == -1)))
4430 if (resume
[ndx
].kind
== resume_stop
4431 && thread
->last_resume_kind
== resume_stop
)
4434 debug_printf ("already %s LWP %ld at GDB's request\n",
4435 (thread
->last_status
.kind
4436 == TARGET_WAITKIND_STOPPED
)
4444 /* Ignore (wildcard) resume requests for already-resumed
4446 if (resume
[ndx
].kind
!= resume_stop
4447 && thread
->last_resume_kind
!= resume_stop
)
4450 debug_printf ("already %s LWP %ld at GDB's request\n",
4451 (thread
->last_resume_kind
4459 /* Don't let wildcard resumes resume fork children that GDB
4460 does not yet know are new fork children. */
4461 if (lwp
->fork_relative
!= NULL
)
4463 struct lwp_info
*rel
= lwp
->fork_relative
;
4465 if (rel
->status_pending_p
4466 && (rel
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
4467 || rel
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
))
4470 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4476 /* If the thread has a pending event that has already been
4477 reported to GDBserver core, but GDB has not pulled the
4478 event out of the vStopped queue yet, likewise, ignore the
4479 (wildcard) resume request. */
4480 if (in_queued_stop_replies (thread
->id
))
4483 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4488 lwp
->resume
= &resume
[ndx
];
4489 thread
->last_resume_kind
= lwp
->resume
->kind
;
4491 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4492 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4494 /* If we had a deferred signal to report, dequeue one now.
4495 This can happen if LWP gets more than one signal while
4496 trying to get out of a jump pad. */
4498 && !lwp
->status_pending_p
4499 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4501 lwp
->status_pending_p
= 1;
4504 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4505 "leaving status pending.\n",
4506 WSTOPSIG (lwp
->status_pending
),
4514 /* No resume action for this thread. */
4519 linux_process_target::resume_status_pending (thread_info
*thread
)
4521 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4523 /* LWPs which will not be resumed are not interesting, because
4524 we might not wait for them next time through linux_wait. */
4525 if (lwp
->resume
== NULL
)
4528 return thread_still_has_status_pending (thread
);
4532 linux_process_target::thread_needs_step_over (thread_info
*thread
)
4534 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4535 struct thread_info
*saved_thread
;
4537 struct process_info
*proc
= get_thread_process (thread
);
4539 /* GDBserver is skipping the extra traps from the wrapper program,
4540 don't have to do step over. */
4541 if (proc
->tdesc
== NULL
)
4544 /* LWPs which will not be resumed are not interesting, because we
4545 might not wait for them next time through linux_wait. */
4550 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4555 if (thread
->last_resume_kind
== resume_stop
)
4558 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4564 gdb_assert (lwp
->suspended
>= 0);
4569 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4574 if (lwp
->status_pending_p
)
4577 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4583 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4587 /* If the PC has changed since we stopped, then don't do anything,
4588 and let the breakpoint/tracepoint be hit. This happens if, for
4589 instance, GDB handled the decr_pc_after_break subtraction itself,
4590 GDB is OOL stepping this thread, or the user has issued a "jump"
4591 command, or poked thread's registers herself. */
4592 if (pc
!= lwp
->stop_pc
)
4595 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4596 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4598 paddress (lwp
->stop_pc
), paddress (pc
));
4602 /* On software single step target, resume the inferior with signal
4603 rather than stepping over. */
4604 if (supports_software_single_step ()
4605 && lwp
->pending_signals
!= NULL
4606 && lwp_signal_can_be_delivered (lwp
))
4609 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4616 saved_thread
= current_thread
;
4617 current_thread
= thread
;
4619 /* We can only step over breakpoints we know about. */
4620 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4622 /* Don't step over a breakpoint that GDB expects to hit
4623 though. If the condition is being evaluated on the target's side
4624 and it evaluate to false, step over this breakpoint as well. */
4625 if (gdb_breakpoint_here (pc
)
4626 && gdb_condition_true_at_breakpoint (pc
)
4627 && gdb_no_commands_at_breakpoint (pc
))
4630 debug_printf ("Need step over [LWP %ld]? yes, but found"
4631 " GDB breakpoint at 0x%s; skipping step over\n",
4632 lwpid_of (thread
), paddress (pc
));
4634 current_thread
= saved_thread
;
4640 debug_printf ("Need step over [LWP %ld]? yes, "
4641 "found breakpoint at 0x%s\n",
4642 lwpid_of (thread
), paddress (pc
));
4644 /* We've found an lwp that needs stepping over --- return 1 so
4645 that find_thread stops looking. */
4646 current_thread
= saved_thread
;
4652 current_thread
= saved_thread
;
4655 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4657 lwpid_of (thread
), paddress (pc
));
4663 linux_process_target::start_step_over (lwp_info
*lwp
)
4665 struct thread_info
*thread
= get_lwp_thread (lwp
);
4666 struct thread_info
*saved_thread
;
4671 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4674 stop_all_lwps (1, lwp
);
4676 if (lwp
->suspended
!= 0)
4678 internal_error (__FILE__
, __LINE__
,
4679 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4684 debug_printf ("Done stopping all threads for step-over.\n");
4686 /* Note, we should always reach here with an already adjusted PC,
4687 either by GDB (if we're resuming due to GDB's request), or by our
4688 caller, if we just finished handling an internal breakpoint GDB
4689 shouldn't care about. */
4692 saved_thread
= current_thread
;
4693 current_thread
= thread
;
4695 lwp
->bp_reinsert
= pc
;
4696 uninsert_breakpoints_at (pc
);
4697 uninsert_fast_tracepoint_jumps_at (pc
);
4699 step
= single_step (lwp
);
4701 current_thread
= saved_thread
;
4703 resume_one_lwp (lwp
, step
, 0, NULL
);
4705 /* Require next event from this LWP. */
4706 step_over_bkpt
= thread
->id
;
4709 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4710 start_step_over, if still there, and delete any single-step
4711 breakpoints we've set, on non hardware single-step targets. */
4714 finish_step_over (struct lwp_info
*lwp
)
4716 if (lwp
->bp_reinsert
!= 0)
4718 struct thread_info
*saved_thread
= current_thread
;
4721 debug_printf ("Finished step over.\n");
4723 current_thread
= get_lwp_thread (lwp
);
4725 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4726 may be no breakpoint to reinsert there by now. */
4727 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4728 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4730 lwp
->bp_reinsert
= 0;
4732 /* Delete any single-step breakpoints. No longer needed. We
4733 don't have to worry about other threads hitting this trap,
4734 and later not being able to explain it, because we were
4735 stepping over a breakpoint, and we hold all threads but
4736 LWP stopped while doing that. */
4737 if (!can_hardware_single_step ())
4739 gdb_assert (has_single_step_breakpoints (current_thread
));
4740 delete_single_step_breakpoints (current_thread
);
4743 step_over_bkpt
= null_ptid
;
4744 current_thread
= saved_thread
;
4752 linux_process_target::complete_ongoing_step_over ()
4754 if (step_over_bkpt
!= null_ptid
)
4756 struct lwp_info
*lwp
;
4761 debug_printf ("detach: step over in progress, finish it first\n");
4763 /* Passing NULL_PTID as filter indicates we want all events to
4764 be left pending. Eventually this returns when there are no
4765 unwaited-for children left. */
4766 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
,
4768 gdb_assert (ret
== -1);
4770 lwp
= find_lwp_pid (step_over_bkpt
);
4772 finish_step_over (lwp
);
4773 step_over_bkpt
= null_ptid
;
4774 unsuspend_all_lwps (lwp
);
4779 linux_process_target::resume_one_thread (thread_info
*thread
,
4780 bool leave_all_stopped
)
4782 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4785 if (lwp
->resume
== NULL
)
4788 if (lwp
->resume
->kind
== resume_stop
)
4791 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4796 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4798 /* Stop the thread, and wait for the event asynchronously,
4799 through the event loop. */
4805 debug_printf ("already stopped LWP %ld\n",
4808 /* The LWP may have been stopped in an internal event that
4809 was not meant to be notified back to GDB (e.g., gdbserver
4810 breakpoint), so we should be reporting a stop event in
4813 /* If the thread already has a pending SIGSTOP, this is a
4814 no-op. Otherwise, something later will presumably resume
4815 the thread and this will cause it to cancel any pending
4816 operation, due to last_resume_kind == resume_stop. If
4817 the thread already has a pending status to report, we
4818 will still report it the next time we wait - see
4819 status_pending_p_callback. */
4821 /* If we already have a pending signal to report, then
4822 there's no need to queue a SIGSTOP, as this means we're
4823 midway through moving the LWP out of the jumppad, and we
4824 will report the pending signal as soon as that is
4826 if (lwp
->pending_signals_to_report
== NULL
)
4830 /* For stop requests, we're done. */
4832 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4836 /* If this thread which is about to be resumed has a pending status,
4837 then don't resume it - we can just report the pending status.
4838 Likewise if it is suspended, because e.g., another thread is
4839 stepping past a breakpoint. Make sure to queue any signals that
4840 would otherwise be sent. In all-stop mode, we do this decision
4841 based on if *any* thread has a pending status. If there's a
4842 thread that needs the step-over-breakpoint dance, then don't
4843 resume any other thread but that particular one. */
4844 leave_pending
= (lwp
->suspended
4845 || lwp
->status_pending_p
4846 || leave_all_stopped
);
4848 /* If we have a new signal, enqueue the signal. */
4849 if (lwp
->resume
->sig
!= 0)
4851 siginfo_t info
, *info_p
;
4853 /* If this is the same signal we were previously stopped by,
4854 make sure to queue its siginfo. */
4855 if (WIFSTOPPED (lwp
->last_status
)
4856 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
4857 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
),
4858 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
4863 enqueue_pending_signal (lwp
, lwp
->resume
->sig
, info_p
);
4869 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4871 proceed_one_lwp (thread
, NULL
);
4876 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4879 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4884 linux_process_target::resume (thread_resume
*resume_info
, size_t n
)
4886 struct thread_info
*need_step_over
= NULL
;
4891 debug_printf ("linux_resume:\n");
4894 for_each_thread ([&] (thread_info
*thread
)
4896 linux_set_resume_request (thread
, resume_info
, n
);
4899 /* If there is a thread which would otherwise be resumed, which has
4900 a pending status, then don't resume any threads - we can just
4901 report the pending status. Make sure to queue any signals that
4902 would otherwise be sent. In non-stop mode, we'll apply this
4903 logic to each thread individually. We consume all pending events
4904 before considering to start a step-over (in all-stop). */
4905 bool any_pending
= false;
4907 any_pending
= find_thread ([this] (thread_info
*thread
)
4909 return resume_status_pending (thread
);
4912 /* If there is a thread which would otherwise be resumed, which is
4913 stopped at a breakpoint that needs stepping over, then don't
4914 resume any threads - have it step over the breakpoint with all
4915 other threads stopped, then resume all threads again. Make sure
4916 to queue any signals that would otherwise be delivered or
4918 if (!any_pending
&& low_supports_breakpoints ())
4919 need_step_over
= find_thread ([this] (thread_info
*thread
)
4921 return thread_needs_step_over (thread
);
4924 bool leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4928 if (need_step_over
!= NULL
)
4929 debug_printf ("Not resuming all, need step over\n");
4930 else if (any_pending
)
4931 debug_printf ("Not resuming, all-stop and found "
4932 "an LWP with pending status\n");
4934 debug_printf ("Resuming, no pending status or step over needed\n");
4937 /* Even if we're leaving threads stopped, queue all signals we'd
4938 otherwise deliver. */
4939 for_each_thread ([&] (thread_info
*thread
)
4941 resume_one_thread (thread
, leave_all_stopped
);
4945 start_step_over (get_thread_lwp (need_step_over
));
4949 debug_printf ("linux_resume done\n");
4953 /* We may have events that were pending that can/should be sent to
4954 the client now. Trigger a linux_wait call. */
4955 if (target_is_async_p ())
4960 linux_process_target::proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
4962 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4969 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4974 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4978 if (thread
->last_resume_kind
== resume_stop
4979 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4982 debug_printf (" client wants LWP to remain %ld stopped\n",
4987 if (lwp
->status_pending_p
)
4990 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4995 gdb_assert (lwp
->suspended
>= 0);
5000 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
5004 if (thread
->last_resume_kind
== resume_stop
5005 && lwp
->pending_signals_to_report
== NULL
5006 && (lwp
->collecting_fast_tracepoint
5007 == fast_tpoint_collect_result::not_collecting
))
5009 /* We haven't reported this LWP as stopped yet (otherwise, the
5010 last_status.kind check above would catch it, and we wouldn't
5011 reach here. This LWP may have been momentarily paused by a
5012 stop_all_lwps call while handling for example, another LWP's
5013 step-over. In that case, the pending expected SIGSTOP signal
5014 that was queued at vCont;t handling time will have already
5015 been consumed by wait_for_sigstop, and so we need to requeue
5016 another one here. Note that if the LWP already has a SIGSTOP
5017 pending, this is a no-op. */
5020 debug_printf ("Client wants LWP %ld to stop. "
5021 "Making sure it has a SIGSTOP pending\n",
5027 if (thread
->last_resume_kind
== resume_step
)
5030 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5033 /* If resume_step is requested by GDB, install single-step
5034 breakpoints when the thread is about to be actually resumed if
5035 the single-step breakpoints weren't removed. */
5036 if (supports_software_single_step ()
5037 && !has_single_step_breakpoints (thread
))
5038 install_software_single_step_breakpoints (lwp
);
5040 step
= maybe_hw_step (thread
);
5042 else if (lwp
->bp_reinsert
!= 0)
5045 debug_printf (" stepping LWP %ld, reinsert set\n",
5048 step
= maybe_hw_step (thread
);
5053 resume_one_lwp (lwp
, step
, 0, NULL
);
5057 linux_process_target::unsuspend_and_proceed_one_lwp (thread_info
*thread
,
5060 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5065 lwp_suspended_decr (lwp
);
5067 proceed_one_lwp (thread
, except
);
5071 linux_process_target::proceed_all_lwps ()
5073 struct thread_info
*need_step_over
;
5075 /* If there is a thread which would otherwise be resumed, which is
5076 stopped at a breakpoint that needs stepping over, then don't
5077 resume any threads - have it step over the breakpoint with all
5078 other threads stopped, then resume all threads again. */
5080 if (low_supports_breakpoints ())
5082 need_step_over
= find_thread ([this] (thread_info
*thread
)
5084 return thread_needs_step_over (thread
);
5087 if (need_step_over
!= NULL
)
5090 debug_printf ("proceed_all_lwps: found "
5091 "thread %ld needing a step-over\n",
5092 lwpid_of (need_step_over
));
5094 start_step_over (get_thread_lwp (need_step_over
));
5100 debug_printf ("Proceeding, no step-over needed\n");
5102 for_each_thread ([this] (thread_info
*thread
)
5104 proceed_one_lwp (thread
, NULL
);
5109 linux_process_target::unstop_all_lwps (int unsuspend
, lwp_info
*except
)
5115 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5116 lwpid_of (get_lwp_thread (except
)));
5118 debug_printf ("unstopping all lwps\n");
5122 for_each_thread ([&] (thread_info
*thread
)
5124 unsuspend_and_proceed_one_lwp (thread
, except
);
5127 for_each_thread ([&] (thread_info
*thread
)
5129 proceed_one_lwp (thread
, except
);
5134 debug_printf ("unstop_all_lwps done\n");
5140 #ifdef HAVE_LINUX_REGSETS
5142 #define use_linux_regsets 1
5144 /* Returns true if REGSET has been disabled. */
5147 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5149 return (info
->disabled_regsets
!= NULL
5150 && info
->disabled_regsets
[regset
- info
->regsets
]);
5153 /* Disable REGSET. */
5156 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5160 dr_offset
= regset
- info
->regsets
;
5161 if (info
->disabled_regsets
== NULL
)
5162 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5163 info
->disabled_regsets
[dr_offset
] = 1;
5167 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5168 struct regcache
*regcache
)
5170 struct regset_info
*regset
;
5171 int saw_general_regs
= 0;
5175 pid
= lwpid_of (current_thread
);
5176 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5181 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5184 buf
= xmalloc (regset
->size
);
5186 nt_type
= regset
->nt_type
;
5190 iov
.iov_len
= regset
->size
;
5191 data
= (void *) &iov
;
5197 res
= ptrace (regset
->get_request
, pid
,
5198 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5200 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5205 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
5207 /* If we get EIO on a regset, or an EINVAL and the regset is
5208 optional, do not try it again for this process mode. */
5209 disable_regset (regsets_info
, regset
);
5211 else if (errno
== ENODATA
)
5213 /* ENODATA may be returned if the regset is currently
5214 not "active". This can happen in normal operation,
5215 so suppress the warning in this case. */
5217 else if (errno
== ESRCH
)
5219 /* At this point, ESRCH should mean the process is
5220 already gone, in which case we simply ignore attempts
5221 to read its registers. */
5226 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5233 if (regset
->type
== GENERAL_REGS
)
5234 saw_general_regs
= 1;
5235 regset
->store_function (regcache
, buf
);
5239 if (saw_general_regs
)
5246 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5247 struct regcache
*regcache
)
5249 struct regset_info
*regset
;
5250 int saw_general_regs
= 0;
5254 pid
= lwpid_of (current_thread
);
5255 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5260 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5261 || regset
->fill_function
== NULL
)
5264 buf
= xmalloc (regset
->size
);
5266 /* First fill the buffer with the current register set contents,
5267 in case there are any items in the kernel's regset that are
5268 not in gdbserver's regcache. */
5270 nt_type
= regset
->nt_type
;
5274 iov
.iov_len
= regset
->size
;
5275 data
= (void *) &iov
;
5281 res
= ptrace (regset
->get_request
, pid
,
5282 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5284 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5289 /* Then overlay our cached registers on that. */
5290 regset
->fill_function (regcache
, buf
);
5292 /* Only now do we write the register set. */
5294 res
= ptrace (regset
->set_request
, pid
,
5295 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5297 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5304 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
5306 /* If we get EIO on a regset, or an EINVAL and the regset is
5307 optional, do not try it again for this process mode. */
5308 disable_regset (regsets_info
, regset
);
5310 else if (errno
== ESRCH
)
5312 /* At this point, ESRCH should mean the process is
5313 already gone, in which case we simply ignore attempts
5314 to change its registers. See also the related
5315 comment in resume_one_lwp. */
5321 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5324 else if (regset
->type
== GENERAL_REGS
)
5325 saw_general_regs
= 1;
5328 if (saw_general_regs
)
5334 #else /* !HAVE_LINUX_REGSETS */
5336 #define use_linux_regsets 0
5337 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5338 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5342 /* Return 1 if register REGNO is supported by one of the regset ptrace
5343 calls or 0 if it has to be transferred individually. */
5346 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5348 unsigned char mask
= 1 << (regno
% 8);
5349 size_t index
= regno
/ 8;
5351 return (use_linux_regsets
5352 && (regs_info
->regset_bitmap
== NULL
5353 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5356 #ifdef HAVE_LINUX_USRREGS
5359 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5363 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5364 error ("Invalid register number %d.", regnum
);
5366 addr
= usrregs
->regmap
[regnum
];
5373 linux_process_target::fetch_register (const usrregs_info
*usrregs
,
5374 regcache
*regcache
, int regno
)
5381 if (regno
>= usrregs
->num_regs
)
5383 if (low_cannot_fetch_register (regno
))
5386 regaddr
= register_addr (usrregs
, regno
);
5390 size
= ((register_size (regcache
->tdesc
, regno
)
5391 + sizeof (PTRACE_XFER_TYPE
) - 1)
5392 & -sizeof (PTRACE_XFER_TYPE
));
5393 buf
= (char *) alloca (size
);
5395 pid
= lwpid_of (current_thread
);
5396 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5399 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5400 ptrace (PTRACE_PEEKUSER
, pid
,
5401 /* Coerce to a uintptr_t first to avoid potential gcc warning
5402 of coercing an 8 byte integer to a 4 byte pointer. */
5403 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5404 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5407 /* Mark register REGNO unavailable. */
5408 supply_register (regcache
, regno
, NULL
);
5413 low_supply_ptrace_register (regcache
, regno
, buf
);
5417 linux_process_target::store_register (const usrregs_info
*usrregs
,
5418 regcache
*regcache
, int regno
)
5425 if (regno
>= usrregs
->num_regs
)
5427 if (low_cannot_store_register (regno
))
5430 regaddr
= register_addr (usrregs
, regno
);
5434 size
= ((register_size (regcache
->tdesc
, regno
)
5435 + sizeof (PTRACE_XFER_TYPE
) - 1)
5436 & -sizeof (PTRACE_XFER_TYPE
));
5437 buf
= (char *) alloca (size
);
5438 memset (buf
, 0, size
);
5440 low_collect_ptrace_register (regcache
, regno
, buf
);
5442 pid
= lwpid_of (current_thread
);
5443 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5446 ptrace (PTRACE_POKEUSER
, pid
,
5447 /* Coerce to a uintptr_t first to avoid potential gcc warning
5448 about coercing an 8 byte integer to a 4 byte pointer. */
5449 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5450 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5453 /* At this point, ESRCH should mean the process is
5454 already gone, in which case we simply ignore attempts
5455 to change its registers. See also the related
5456 comment in resume_one_lwp. */
5461 if (!low_cannot_store_register (regno
))
5462 error ("writing register %d: %s", regno
, safe_strerror (errno
));
5464 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5467 #endif /* HAVE_LINUX_USRREGS */
5470 linux_process_target::low_collect_ptrace_register (regcache
*regcache
,
5471 int regno
, char *buf
)
5473 collect_register (regcache
, regno
, buf
);
5477 linux_process_target::low_supply_ptrace_register (regcache
*regcache
,
5478 int regno
, const char *buf
)
5480 supply_register (regcache
, regno
, buf
);
5484 linux_process_target::usr_fetch_inferior_registers (const regs_info
*regs_info
,
5488 #ifdef HAVE_LINUX_USRREGS
5489 struct usrregs_info
*usr
= regs_info
->usrregs
;
5493 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5494 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5495 fetch_register (usr
, regcache
, regno
);
5498 fetch_register (usr
, regcache
, regno
);
5503 linux_process_target::usr_store_inferior_registers (const regs_info
*regs_info
,
5507 #ifdef HAVE_LINUX_USRREGS
5508 struct usrregs_info
*usr
= regs_info
->usrregs
;
5512 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5513 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5514 store_register (usr
, regcache
, regno
);
5517 store_register (usr
, regcache
, regno
);
5522 linux_process_target::fetch_registers (regcache
*regcache
, int regno
)
5526 const regs_info
*regs_info
= get_regs_info ();
5530 if (regs_info
->usrregs
!= NULL
)
5531 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5532 low_fetch_register (regcache
, regno
);
5534 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5535 if (regs_info
->usrregs
!= NULL
)
5536 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5540 if (low_fetch_register (regcache
, regno
))
5543 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5545 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5547 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5548 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5553 linux_process_target::store_registers (regcache
*regcache
, int regno
)
5557 const regs_info
*regs_info
= get_regs_info ();
5561 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5563 if (regs_info
->usrregs
!= NULL
)
5564 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5568 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5570 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5572 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5573 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5578 linux_process_target::low_fetch_register (regcache
*regcache
, int regno
)
5583 /* A wrapper for the read_memory target op. */
5586 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5588 return the_target
->read_memory (memaddr
, myaddr
, len
);
5591 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5592 to debugger memory starting at MYADDR. */
5595 linux_process_target::read_memory (CORE_ADDR memaddr
,
5596 unsigned char *myaddr
, int len
)
5598 int pid
= lwpid_of (current_thread
);
5599 PTRACE_XFER_TYPE
*buffer
;
5607 /* Try using /proc. Don't bother for one word. */
5608 if (len
>= 3 * sizeof (long))
5612 /* We could keep this file open and cache it - possibly one per
5613 thread. That requires some juggling, but is even faster. */
5614 sprintf (filename
, "/proc/%d/mem", pid
);
5615 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5619 /* If pread64 is available, use it. It's faster if the kernel
5620 supports it (only one syscall), and it's 64-bit safe even on
5621 32-bit platforms (for instance, SPARC debugging a SPARC64
5624 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5627 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5628 bytes
= read (fd
, myaddr
, len
);
5635 /* Some data was read, we'll try to get the rest with ptrace. */
5645 /* Round starting address down to longword boundary. */
5646 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5647 /* Round ending address up; get number of longwords that makes. */
5648 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5649 / sizeof (PTRACE_XFER_TYPE
));
5650 /* Allocate buffer of that many longwords. */
5651 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5653 /* Read all the longwords */
5655 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5657 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5658 about coercing an 8 byte integer to a 4 byte pointer. */
5659 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5660 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5661 (PTRACE_TYPE_ARG4
) 0);
5667 /* Copy appropriate bytes out of the buffer. */
5670 i
*= sizeof (PTRACE_XFER_TYPE
);
5671 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5673 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5680 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5681 memory at MEMADDR. On failure (cannot write to the inferior)
5682 returns the value of errno. Always succeeds if LEN is zero. */
5685 linux_process_target::write_memory (CORE_ADDR memaddr
,
5686 const unsigned char *myaddr
, int len
)
5689 /* Round starting address down to longword boundary. */
5690 CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5691 /* Round ending address up; get number of longwords that makes. */
5693 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5694 / sizeof (PTRACE_XFER_TYPE
);
5696 /* Allocate buffer of that many longwords. */
5697 PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5699 int pid
= lwpid_of (current_thread
);
5703 /* Zero length write always succeeds. */
5709 /* Dump up to four bytes. */
5710 char str
[4 * 2 + 1];
5712 int dump
= len
< 4 ? len
: 4;
5714 for (i
= 0; i
< dump
; i
++)
5716 sprintf (p
, "%02x", myaddr
[i
]);
5721 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5722 str
, (long) memaddr
, pid
);
5725 /* Fill start and end extra bytes of buffer with existing memory data. */
5728 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5729 about coercing an 8 byte integer to a 4 byte pointer. */
5730 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5731 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5732 (PTRACE_TYPE_ARG4
) 0);
5740 = ptrace (PTRACE_PEEKTEXT
, pid
,
5741 /* Coerce to a uintptr_t first to avoid potential gcc warning
5742 about coercing an 8 byte integer to a 4 byte pointer. */
5743 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5744 * sizeof (PTRACE_XFER_TYPE
)),
5745 (PTRACE_TYPE_ARG4
) 0);
5750 /* Copy data to be written over corresponding part of buffer. */
5752 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5755 /* Write the entire buffer. */
5757 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5760 ptrace (PTRACE_POKETEXT
, pid
,
5761 /* Coerce to a uintptr_t first to avoid potential gcc warning
5762 about coercing an 8 byte integer to a 4 byte pointer. */
5763 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5764 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5773 linux_process_target::look_up_symbols ()
5775 #ifdef USE_THREAD_DB
5776 struct process_info
*proc
= current_process ();
5778 if (proc
->priv
->thread_db
!= NULL
)
5786 linux_process_target::request_interrupt ()
5788 /* Send a SIGINT to the process group. This acts just like the user
5789 typed a ^C on the controlling terminal. */
5790 ::kill (-signal_pid
, SIGINT
);
5794 linux_process_target::supports_read_auxv ()
5799 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5800 to debugger memory starting at MYADDR. */
5803 linux_process_target::read_auxv (CORE_ADDR offset
, unsigned char *myaddr
,
5806 char filename
[PATH_MAX
];
5808 int pid
= lwpid_of (current_thread
);
5810 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5812 fd
= open (filename
, O_RDONLY
);
5816 if (offset
!= (CORE_ADDR
) 0
5817 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5820 n
= read (fd
, myaddr
, len
);
5828 linux_process_target::insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5829 int size
, raw_breakpoint
*bp
)
5831 if (type
== raw_bkpt_type_sw
)
5832 return insert_memory_breakpoint (bp
);
5834 return low_insert_point (type
, addr
, size
, bp
);
5838 linux_process_target::low_insert_point (raw_bkpt_type type
, CORE_ADDR addr
,
5839 int size
, raw_breakpoint
*bp
)
5841 /* Unsupported (see target.h). */
5846 linux_process_target::remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5847 int size
, raw_breakpoint
*bp
)
5849 if (type
== raw_bkpt_type_sw
)
5850 return remove_memory_breakpoint (bp
);
5852 return low_remove_point (type
, addr
, size
, bp
);
5856 linux_process_target::low_remove_point (raw_bkpt_type type
, CORE_ADDR addr
,
5857 int size
, raw_breakpoint
*bp
)
5859 /* Unsupported (see target.h). */
5863 /* Implement the stopped_by_sw_breakpoint target_ops
5867 linux_process_target::stopped_by_sw_breakpoint ()
5869 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5871 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5874 /* Implement the supports_stopped_by_sw_breakpoint target_ops
5878 linux_process_target::supports_stopped_by_sw_breakpoint ()
5880 return USE_SIGTRAP_SIGINFO
;
5883 /* Implement the stopped_by_hw_breakpoint target_ops
5887 linux_process_target::stopped_by_hw_breakpoint ()
5889 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5891 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5894 /* Implement the supports_stopped_by_hw_breakpoint target_ops
5898 linux_process_target::supports_stopped_by_hw_breakpoint ()
5900 return USE_SIGTRAP_SIGINFO
;
5903 /* Implement the supports_hardware_single_step target_ops method. */
5906 linux_process_target::supports_hardware_single_step ()
5908 return can_hardware_single_step ();
5912 linux_process_target::stopped_by_watchpoint ()
5914 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5916 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5920 linux_process_target::stopped_data_address ()
5922 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5924 return lwp
->stopped_data_address
;
5927 /* This is only used for targets that define PT_TEXT_ADDR,
5928 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5929 the target has different ways of acquiring this information, like
5933 linux_process_target::supports_read_offsets ()
5935 #ifdef SUPPORTS_READ_OFFSETS
5942 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5943 to tell gdb about. */
5946 linux_process_target::read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5948 #ifdef SUPPORTS_READ_OFFSETS
5949 unsigned long text
, text_end
, data
;
5950 int pid
= lwpid_of (current_thread
);
5954 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5955 (PTRACE_TYPE_ARG4
) 0);
5956 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5957 (PTRACE_TYPE_ARG4
) 0);
5958 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5959 (PTRACE_TYPE_ARG4
) 0);
5963 /* Both text and data offsets produced at compile-time (and so
5964 used by gdb) are relative to the beginning of the program,
5965 with the data segment immediately following the text segment.
5966 However, the actual runtime layout in memory may put the data
5967 somewhere else, so when we send gdb a data base-address, we
5968 use the real data base address and subtract the compile-time
5969 data base-address from it (which is just the length of the
5970 text segment). BSS immediately follows data in both
5973 *data_p
= data
- (text_end
- text
);
5979 gdb_assert_not_reached ("target op read_offsets not supported");
5984 linux_process_target::supports_get_tls_address ()
5986 #ifdef USE_THREAD_DB
5994 linux_process_target::get_tls_address (thread_info
*thread
,
5996 CORE_ADDR load_module
,
5999 #ifdef USE_THREAD_DB
6000 return thread_db_get_tls_address (thread
, offset
, load_module
, address
);
6007 linux_process_target::supports_qxfer_osdata ()
6013 linux_process_target::qxfer_osdata (const char *annex
,
6014 unsigned char *readbuf
,
6015 unsigned const char *writebuf
,
6016 CORE_ADDR offset
, int len
)
6018 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
6022 linux_process_target::siginfo_fixup (siginfo_t
*siginfo
,
6023 gdb_byte
*inf_siginfo
, int direction
)
6025 bool done
= low_siginfo_fixup (siginfo
, inf_siginfo
, direction
);
6027 /* If there was no callback, or the callback didn't do anything,
6028 then just do a straight memcpy. */
6032 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
6034 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
6039 linux_process_target::low_siginfo_fixup (siginfo_t
*native
, gdb_byte
*inf
,
6046 linux_process_target::supports_qxfer_siginfo ()
6052 linux_process_target::qxfer_siginfo (const char *annex
,
6053 unsigned char *readbuf
,
6054 unsigned const char *writebuf
,
6055 CORE_ADDR offset
, int len
)
6059 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
6061 if (current_thread
== NULL
)
6064 pid
= lwpid_of (current_thread
);
6067 debug_printf ("%s siginfo for lwp %d.\n",
6068 readbuf
!= NULL
? "Reading" : "Writing",
6071 if (offset
>= sizeof (siginfo
))
6074 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6077 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6078 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6079 inferior with a 64-bit GDBSERVER should look the same as debugging it
6080 with a 32-bit GDBSERVER, we need to convert it. */
6081 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
6083 if (offset
+ len
> sizeof (siginfo
))
6084 len
= sizeof (siginfo
) - offset
;
6086 if (readbuf
!= NULL
)
6087 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6090 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6092 /* Convert back to ptrace layout before flushing it out. */
6093 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6095 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6102 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6103 so we notice when children change state; as the handler for the
6104 sigsuspend in my_waitpid. */
6107 sigchld_handler (int signo
)
6109 int old_errno
= errno
;
6115 /* Use the async signal safe debug function. */
6116 if (debug_write ("sigchld_handler\n",
6117 sizeof ("sigchld_handler\n") - 1) < 0)
6118 break; /* just ignore */
6122 if (target_is_async_p ())
6123 async_file_mark (); /* trigger a linux_wait */
6129 linux_process_target::supports_non_stop ()
6135 linux_process_target::async (bool enable
)
6137 bool previous
= target_is_async_p ();
6140 debug_printf ("linux_async (%d), previous=%d\n",
6143 if (previous
!= enable
)
6146 sigemptyset (&mask
);
6147 sigaddset (&mask
, SIGCHLD
);
6149 gdb_sigmask (SIG_BLOCK
, &mask
, NULL
);
6153 if (pipe (linux_event_pipe
) == -1)
6155 linux_event_pipe
[0] = -1;
6156 linux_event_pipe
[1] = -1;
6157 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
6159 warning ("creating event pipe failed.");
6163 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6164 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6166 /* Register the event loop handler. */
6167 add_file_handler (linux_event_pipe
[0],
6168 handle_target_event
, NULL
);
6170 /* Always trigger a linux_wait. */
6175 delete_file_handler (linux_event_pipe
[0]);
6177 close (linux_event_pipe
[0]);
6178 close (linux_event_pipe
[1]);
6179 linux_event_pipe
[0] = -1;
6180 linux_event_pipe
[1] = -1;
6183 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
6190 linux_process_target::start_non_stop (bool nonstop
)
6192 /* Register or unregister from event-loop accordingly. */
6193 target_async (nonstop
);
6195 if (target_is_async_p () != (nonstop
!= false))
6202 linux_process_target::supports_multi_process ()
6207 /* Check if fork events are supported. */
6210 linux_process_target::supports_fork_events ()
6212 return linux_supports_tracefork ();
6215 /* Check if vfork events are supported. */
6218 linux_process_target::supports_vfork_events ()
6220 return linux_supports_tracefork ();
6223 /* Check if exec events are supported. */
6226 linux_process_target::supports_exec_events ()
6228 return linux_supports_traceexec ();
6231 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6232 ptrace flags for all inferiors. This is in case the new GDB connection
6233 doesn't support the same set of events that the previous one did. */
6236 linux_process_target::handle_new_gdb_connection ()
6238 /* Request that all the lwps reset their ptrace options. */
6239 for_each_thread ([] (thread_info
*thread
)
6241 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6245 /* Stop the lwp so we can modify its ptrace options. */
6246 lwp
->must_set_ptrace_flags
= 1;
6247 linux_stop_lwp (lwp
);
6251 /* Already stopped; go ahead and set the ptrace options. */
6252 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6253 int options
= linux_low_ptrace_options (proc
->attached
);
6255 linux_enable_event_reporting (lwpid_of (thread
), options
);
6256 lwp
->must_set_ptrace_flags
= 0;
6262 linux_process_target::handle_monitor_command (char *mon
)
6264 #ifdef USE_THREAD_DB
6265 return thread_db_handle_monitor_command (mon
);
6272 linux_process_target::core_of_thread (ptid_t ptid
)
6274 return linux_common_core_of_thread (ptid
);
6278 linux_process_target::supports_disable_randomization ()
6280 #ifdef HAVE_PERSONALITY
6288 linux_process_target::supports_agent ()
6294 linux_process_target::supports_range_stepping ()
6296 if (supports_software_single_step ())
6298 if (*the_low_target
.supports_range_stepping
== NULL
)
6301 return (*the_low_target
.supports_range_stepping
) ();
6305 linux_process_target::supports_pid_to_exec_file ()
6311 linux_process_target::pid_to_exec_file (int pid
)
6313 return linux_proc_pid_to_exec_file (pid
);
6317 linux_process_target::supports_multifs ()
6323 linux_process_target::multifs_open (int pid
, const char *filename
,
6324 int flags
, mode_t mode
)
6326 return linux_mntns_open_cloexec (pid
, filename
, flags
, mode
);
6330 linux_process_target::multifs_unlink (int pid
, const char *filename
)
6332 return linux_mntns_unlink (pid
, filename
);
6336 linux_process_target::multifs_readlink (int pid
, const char *filename
,
6337 char *buf
, size_t bufsiz
)
6339 return linux_mntns_readlink (pid
, filename
, buf
, bufsiz
);
6342 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6343 struct target_loadseg
6345 /* Core address to which the segment is mapped. */
6347 /* VMA recorded in the program header. */
6349 /* Size of this segment in memory. */
6353 # if defined PT_GETDSBT
6354 struct target_loadmap
6356 /* Protocol version number, must be zero. */
6358 /* Pointer to the DSBT table, its size, and the DSBT index. */
6359 unsigned *dsbt_table
;
6360 unsigned dsbt_size
, dsbt_index
;
6361 /* Number of segments in this map. */
6363 /* The actual memory map. */
6364 struct target_loadseg segs
[/*nsegs*/];
6366 # define LINUX_LOADMAP PT_GETDSBT
6367 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6368 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6370 struct target_loadmap
6372 /* Protocol version number, must be zero. */
6374 /* Number of segments in this map. */
6376 /* The actual memory map. */
6377 struct target_loadseg segs
[/*nsegs*/];
6379 # define LINUX_LOADMAP PTRACE_GETFDPIC
6380 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6381 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6385 linux_process_target::supports_read_loadmap ()
6391 linux_process_target::read_loadmap (const char *annex
, CORE_ADDR offset
,
6392 unsigned char *myaddr
, unsigned int len
)
6394 int pid
= lwpid_of (current_thread
);
6396 struct target_loadmap
*data
= NULL
;
6397 unsigned int actual_length
, copy_length
;
6399 if (strcmp (annex
, "exec") == 0)
6400 addr
= (int) LINUX_LOADMAP_EXEC
;
6401 else if (strcmp (annex
, "interp") == 0)
6402 addr
= (int) LINUX_LOADMAP_INTERP
;
6406 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6412 actual_length
= sizeof (struct target_loadmap
)
6413 + sizeof (struct target_loadseg
) * data
->nsegs
;
6415 if (offset
< 0 || offset
> actual_length
)
6418 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6419 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6422 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6425 linux_process_target::process_qsupported (char **features
, int count
)
6427 if (the_low_target
.process_qsupported
!= NULL
)
6428 the_low_target
.process_qsupported (features
, count
);
6432 linux_process_target::supports_catch_syscall ()
6434 return (the_low_target
.get_syscall_trapinfo
!= NULL
6435 && linux_supports_tracesysgood ());
6439 linux_process_target::get_ipa_tdesc_idx ()
6441 if (the_low_target
.get_ipa_tdesc_idx
== NULL
)
6444 return (*the_low_target
.get_ipa_tdesc_idx
) ();
6448 linux_process_target::supports_tracepoints ()
6450 if (*the_low_target
.supports_tracepoints
== NULL
)
6453 return (*the_low_target
.supports_tracepoints
) ();
6457 linux_process_target::read_pc (regcache
*regcache
)
6459 if (!low_supports_breakpoints ())
6462 return low_get_pc (regcache
);
6466 linux_process_target::write_pc (regcache
*regcache
, CORE_ADDR pc
)
6468 gdb_assert (low_supports_breakpoints ());
6470 low_set_pc (regcache
, pc
);
6474 linux_process_target::supports_thread_stopped ()
6480 linux_process_target::thread_stopped (thread_info
*thread
)
6482 return get_thread_lwp (thread
)->stopped
;
6485 /* This exposes stop-all-threads functionality to other modules. */
6488 linux_process_target::pause_all (bool freeze
)
6490 stop_all_lwps (freeze
, NULL
);
6493 /* This exposes unstop-all-threads functionality to other gdbserver
6497 linux_process_target::unpause_all (bool unfreeze
)
6499 unstop_all_lwps (unfreeze
, NULL
);
6503 linux_process_target::prepare_to_access_memory ()
6505 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6508 target_pause_all (true);
6513 linux_process_target::done_accessing_memory ()
6515 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6518 target_unpause_all (true);
6522 linux_process_target::supports_fast_tracepoints ()
6524 return the_low_target
.install_fast_tracepoint_jump_pad
!= nullptr;
6528 linux_process_target::install_fast_tracepoint_jump_pad
6529 (CORE_ADDR tpoint
, CORE_ADDR tpaddr
, CORE_ADDR collector
,
6530 CORE_ADDR lockaddr
, ULONGEST orig_size
, CORE_ADDR
*jump_entry
,
6531 CORE_ADDR
*trampoline
, ULONGEST
*trampoline_size
,
6532 unsigned char *jjump_pad_insn
, ULONGEST
*jjump_pad_insn_size
,
6533 CORE_ADDR
*adjusted_insn_addr
, CORE_ADDR
*adjusted_insn_addr_end
,
6536 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6537 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6538 jump_entry
, trampoline
, trampoline_size
,
6539 jjump_pad_insn
, jjump_pad_insn_size
,
6540 adjusted_insn_addr
, adjusted_insn_addr_end
,
6545 linux_process_target::emit_ops ()
6547 if (the_low_target
.emit_ops
!= NULL
)
6548 return (*the_low_target
.emit_ops
) ();
6554 linux_process_target::get_min_fast_tracepoint_insn_len ()
6556 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6559 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6562 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6563 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6565 char filename
[PATH_MAX
];
6567 const int auxv_size
= is_elf64
6568 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6569 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6571 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6573 fd
= open (filename
, O_RDONLY
);
6579 while (read (fd
, buf
, auxv_size
) == auxv_size
6580 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6584 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6586 switch (aux
->a_type
)
6589 *phdr_memaddr
= aux
->a_un
.a_val
;
6592 *num_phdr
= aux
->a_un
.a_val
;
6598 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6600 switch (aux
->a_type
)
6603 *phdr_memaddr
= aux
->a_un
.a_val
;
6606 *num_phdr
= aux
->a_un
.a_val
;
6614 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6616 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6617 "phdr_memaddr = %ld, phdr_num = %d",
6618 (long) *phdr_memaddr
, *num_phdr
);
6625 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6628 get_dynamic (const int pid
, const int is_elf64
)
6630 CORE_ADDR phdr_memaddr
, relocation
;
6632 unsigned char *phdr_buf
;
6633 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6635 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6638 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6639 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6641 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6644 /* Compute relocation: it is expected to be 0 for "regular" executables,
6645 non-zero for PIE ones. */
6647 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6650 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6652 if (p
->p_type
== PT_PHDR
)
6653 relocation
= phdr_memaddr
- p
->p_vaddr
;
6657 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6659 if (p
->p_type
== PT_PHDR
)
6660 relocation
= phdr_memaddr
- p
->p_vaddr
;
6663 if (relocation
== -1)
6665 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6666 any real world executables, including PIE executables, have always
6667 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6668 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6669 or present DT_DEBUG anyway (fpc binaries are statically linked).
6671 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6673 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6678 for (i
= 0; i
< num_phdr
; i
++)
6682 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6684 if (p
->p_type
== PT_DYNAMIC
)
6685 return p
->p_vaddr
+ relocation
;
6689 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6691 if (p
->p_type
== PT_DYNAMIC
)
6692 return p
->p_vaddr
+ relocation
;
6699 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6700 can be 0 if the inferior does not yet have the library list initialized.
6701 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6702 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6705 get_r_debug (const int pid
, const int is_elf64
)
6707 CORE_ADDR dynamic_memaddr
;
6708 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6709 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6712 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6713 if (dynamic_memaddr
== 0)
6716 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6720 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6721 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6725 unsigned char buf
[sizeof (Elf64_Xword
)];
6729 #ifdef DT_MIPS_RLD_MAP
6730 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6732 if (linux_read_memory (dyn
->d_un
.d_val
,
6733 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6738 #endif /* DT_MIPS_RLD_MAP */
6739 #ifdef DT_MIPS_RLD_MAP_REL
6740 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6742 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6743 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6748 #endif /* DT_MIPS_RLD_MAP_REL */
6750 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6751 map
= dyn
->d_un
.d_val
;
6753 if (dyn
->d_tag
== DT_NULL
)
6758 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6759 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6763 unsigned char buf
[sizeof (Elf32_Word
)];
6767 #ifdef DT_MIPS_RLD_MAP
6768 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6770 if (linux_read_memory (dyn
->d_un
.d_val
,
6771 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6776 #endif /* DT_MIPS_RLD_MAP */
6777 #ifdef DT_MIPS_RLD_MAP_REL
6778 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6780 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6781 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6786 #endif /* DT_MIPS_RLD_MAP_REL */
6788 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6789 map
= dyn
->d_un
.d_val
;
6791 if (dyn
->d_tag
== DT_NULL
)
6795 dynamic_memaddr
+= dyn_size
;
6801 /* Read one pointer from MEMADDR in the inferior. */
6804 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6808 /* Go through a union so this works on either big or little endian
6809 hosts, when the inferior's pointer size is smaller than the size
6810 of CORE_ADDR. It is assumed the inferior's endianness is the
6811 same of the superior's. */
6814 CORE_ADDR core_addr
;
6819 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6822 if (ptr_size
== sizeof (CORE_ADDR
))
6823 *ptr
= addr
.core_addr
;
6824 else if (ptr_size
== sizeof (unsigned int))
6827 gdb_assert_not_reached ("unhandled pointer size");
6833 linux_process_target::supports_qxfer_libraries_svr4 ()
6838 struct link_map_offsets
6840 /* Offset and size of r_debug.r_version. */
6841 int r_version_offset
;
6843 /* Offset and size of r_debug.r_map. */
6846 /* Offset to l_addr field in struct link_map. */
6849 /* Offset to l_name field in struct link_map. */
6852 /* Offset to l_ld field in struct link_map. */
6855 /* Offset to l_next field in struct link_map. */
6858 /* Offset to l_prev field in struct link_map. */
6862 /* Construct qXfer:libraries-svr4:read reply. */
6865 linux_process_target::qxfer_libraries_svr4 (const char *annex
,
6866 unsigned char *readbuf
,
6867 unsigned const char *writebuf
,
6868 CORE_ADDR offset
, int len
)
6870 struct process_info_private
*const priv
= current_process ()->priv
;
6871 char filename
[PATH_MAX
];
6874 static const struct link_map_offsets lmo_32bit_offsets
=
6876 0, /* r_version offset. */
6877 4, /* r_debug.r_map offset. */
6878 0, /* l_addr offset in link_map. */
6879 4, /* l_name offset in link_map. */
6880 8, /* l_ld offset in link_map. */
6881 12, /* l_next offset in link_map. */
6882 16 /* l_prev offset in link_map. */
6885 static const struct link_map_offsets lmo_64bit_offsets
=
6887 0, /* r_version offset. */
6888 8, /* r_debug.r_map offset. */
6889 0, /* l_addr offset in link_map. */
6890 8, /* l_name offset in link_map. */
6891 16, /* l_ld offset in link_map. */
6892 24, /* l_next offset in link_map. */
6893 32 /* l_prev offset in link_map. */
6895 const struct link_map_offsets
*lmo
;
6896 unsigned int machine
;
6898 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6899 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6900 int header_done
= 0;
6902 if (writebuf
!= NULL
)
6904 if (readbuf
== NULL
)
6907 pid
= lwpid_of (current_thread
);
6908 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6909 is_elf64
= elf_64_file_p (filename
, &machine
);
6910 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6911 ptr_size
= is_elf64
? 8 : 4;
6913 while (annex
[0] != '\0')
6919 sep
= strchr (annex
, '=');
6923 name_len
= sep
- annex
;
6924 if (name_len
== 5 && startswith (annex
, "start"))
6926 else if (name_len
== 4 && startswith (annex
, "prev"))
6930 annex
= strchr (sep
, ';');
6937 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6944 if (priv
->r_debug
== 0)
6945 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6947 /* We failed to find DT_DEBUG. Such situation will not change
6948 for this inferior - do not retry it. Report it to GDB as
6949 E01, see for the reasons at the GDB solib-svr4.c side. */
6950 if (priv
->r_debug
== (CORE_ADDR
) -1)
6953 if (priv
->r_debug
!= 0)
6955 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6956 (unsigned char *) &r_version
,
6957 sizeof (r_version
)) != 0
6960 warning ("unexpected r_debug version %d", r_version
);
6962 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6963 &lm_addr
, ptr_size
) != 0)
6965 warning ("unable to read r_map from 0x%lx",
6966 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6971 std::string document
= "<library-list-svr4 version=\"1.0\"";
6974 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6975 &l_name
, ptr_size
) == 0
6976 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6977 &l_addr
, ptr_size
) == 0
6978 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6979 &l_ld
, ptr_size
) == 0
6980 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6981 &l_prev
, ptr_size
) == 0
6982 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6983 &l_next
, ptr_size
) == 0)
6985 unsigned char libname
[PATH_MAX
];
6987 if (lm_prev
!= l_prev
)
6989 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6990 (long) lm_prev
, (long) l_prev
);
6994 /* Ignore the first entry even if it has valid name as the first entry
6995 corresponds to the main executable. The first entry should not be
6996 skipped if the dynamic loader was loaded late by a static executable
6997 (see solib-svr4.c parameter ignore_first). But in such case the main
6998 executable does not have PT_DYNAMIC present and this function already
6999 exited above due to failed get_r_debug. */
7001 string_appendf (document
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
7004 /* Not checking for error because reading may stop before
7005 we've got PATH_MAX worth of characters. */
7007 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
7008 libname
[sizeof (libname
) - 1] = '\0';
7009 if (libname
[0] != '\0')
7013 /* Terminate `<library-list-svr4'. */
7018 string_appendf (document
, "<library name=\"");
7019 xml_escape_text_append (&document
, (char *) libname
);
7020 string_appendf (document
, "\" lm=\"0x%lx\" "
7021 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
7022 (unsigned long) lm_addr
, (unsigned long) l_addr
,
7023 (unsigned long) l_ld
);
7033 /* Empty list; terminate `<library-list-svr4'. */
7037 document
+= "</library-list-svr4>";
7039 int document_len
= document
.length ();
7040 if (offset
< document_len
)
7041 document_len
-= offset
;
7044 if (len
> document_len
)
7047 memcpy (readbuf
, document
.data () + offset
, len
);
7052 #ifdef HAVE_LINUX_BTRACE
7054 btrace_target_info
*
7055 linux_process_target::enable_btrace (ptid_t ptid
,
7056 const btrace_config
*conf
)
7058 return linux_enable_btrace (ptid
, conf
);
7061 /* See to_disable_btrace target method. */
7064 linux_process_target::disable_btrace (btrace_target_info
*tinfo
)
7066 enum btrace_error err
;
7068 err
= linux_disable_btrace (tinfo
);
7069 return (err
== BTRACE_ERR_NONE
? 0 : -1);
7072 /* Encode an Intel Processor Trace configuration. */
7075 linux_low_encode_pt_config (struct buffer
*buffer
,
7076 const struct btrace_data_pt_config
*config
)
7078 buffer_grow_str (buffer
, "<pt-config>\n");
7080 switch (config
->cpu
.vendor
)
7083 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7084 "model=\"%u\" stepping=\"%u\"/>\n",
7085 config
->cpu
.family
, config
->cpu
.model
,
7086 config
->cpu
.stepping
);
7093 buffer_grow_str (buffer
, "</pt-config>\n");
7096 /* Encode a raw buffer. */
7099 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
7105 /* We use hex encoding - see gdbsupport/rsp-low.h. */
7106 buffer_grow_str (buffer
, "<raw>\n");
7112 elem
[0] = tohex ((*data
>> 4) & 0xf);
7113 elem
[1] = tohex (*data
++ & 0xf);
7115 buffer_grow (buffer
, elem
, 2);
7118 buffer_grow_str (buffer
, "</raw>\n");
7121 /* See to_read_btrace target method. */
7124 linux_process_target::read_btrace (btrace_target_info
*tinfo
,
7126 enum btrace_read_type type
)
7128 struct btrace_data btrace
;
7129 enum btrace_error err
;
7131 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7132 if (err
!= BTRACE_ERR_NONE
)
7134 if (err
== BTRACE_ERR_OVERFLOW
)
7135 buffer_grow_str0 (buffer
, "E.Overflow.");
7137 buffer_grow_str0 (buffer
, "E.Generic Error.");
7142 switch (btrace
.format
)
7144 case BTRACE_FORMAT_NONE
:
7145 buffer_grow_str0 (buffer
, "E.No Trace.");
7148 case BTRACE_FORMAT_BTS
:
7149 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7150 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7152 for (const btrace_block
&block
: *btrace
.variant
.bts
.blocks
)
7153 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7154 paddress (block
.begin
), paddress (block
.end
));
7156 buffer_grow_str0 (buffer
, "</btrace>\n");
7159 case BTRACE_FORMAT_PT
:
7160 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7161 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7162 buffer_grow_str (buffer
, "<pt>\n");
7164 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7166 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7167 btrace
.variant
.pt
.size
);
7169 buffer_grow_str (buffer
, "</pt>\n");
7170 buffer_grow_str0 (buffer
, "</btrace>\n");
7174 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7181 /* See to_btrace_conf target method. */
7184 linux_process_target::read_btrace_conf (const btrace_target_info
*tinfo
,
7187 const struct btrace_config
*conf
;
7189 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7190 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7192 conf
= linux_btrace_conf (tinfo
);
7195 switch (conf
->format
)
7197 case BTRACE_FORMAT_NONE
:
7200 case BTRACE_FORMAT_BTS
:
7201 buffer_xml_printf (buffer
, "<bts");
7202 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7203 buffer_xml_printf (buffer
, " />\n");
7206 case BTRACE_FORMAT_PT
:
7207 buffer_xml_printf (buffer
, "<pt");
7208 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7209 buffer_xml_printf (buffer
, "/>\n");
7214 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7217 #endif /* HAVE_LINUX_BTRACE */
7219 /* See nat/linux-nat.h. */
7222 current_lwp_ptid (void)
7224 return ptid_of (current_thread
);
7228 linux_process_target::thread_name (ptid_t thread
)
7230 return linux_proc_tid_get_name (thread
);
7235 linux_process_target::thread_handle (ptid_t ptid
, gdb_byte
**handle
,
7238 return thread_db_thread_handle (ptid
, handle
, handle_len
);
7242 /* Default implementation of linux_target_ops method "set_pc" for
7243 32-bit pc register which is literally named "pc". */
7246 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7248 uint32_t newpc
= pc
;
7250 supply_register_by_name (regcache
, "pc", &newpc
);
7253 /* Default implementation of linux_target_ops method "get_pc" for
7254 32-bit pc register which is literally named "pc". */
7257 linux_get_pc_32bit (struct regcache
*regcache
)
7261 collect_register_by_name (regcache
, "pc", &pc
);
7263 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7267 /* Default implementation of linux_target_ops method "set_pc" for
7268 64-bit pc register which is literally named "pc". */
7271 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7273 uint64_t newpc
= pc
;
7275 supply_register_by_name (regcache
, "pc", &newpc
);
7278 /* Default implementation of linux_target_ops method "get_pc" for
7279 64-bit pc register which is literally named "pc". */
7282 linux_get_pc_64bit (struct regcache
*regcache
)
7286 collect_register_by_name (regcache
, "pc", &pc
);
7288 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7292 /* See linux-low.h. */
7295 linux_get_auxv (int wordsize
, CORE_ADDR match
, CORE_ADDR
*valp
)
7297 gdb_byte
*data
= (gdb_byte
*) alloca (2 * wordsize
);
7300 gdb_assert (wordsize
== 4 || wordsize
== 8);
7302 while (the_target
->read_auxv (offset
, data
, 2 * wordsize
) == 2 * wordsize
)
7306 uint32_t *data_p
= (uint32_t *) data
;
7307 if (data_p
[0] == match
)
7315 uint64_t *data_p
= (uint64_t *) data
;
7316 if (data_p
[0] == match
)
7323 offset
+= 2 * wordsize
;
7329 /* See linux-low.h. */
7332 linux_get_hwcap (int wordsize
)
7334 CORE_ADDR hwcap
= 0;
7335 linux_get_auxv (wordsize
, AT_HWCAP
, &hwcap
);
7339 /* See linux-low.h. */
7342 linux_get_hwcap2 (int wordsize
)
7344 CORE_ADDR hwcap2
= 0;
7345 linux_get_auxv (wordsize
, AT_HWCAP2
, &hwcap2
);
7349 #ifdef HAVE_LINUX_REGSETS
7351 initialize_regsets_info (struct regsets_info
*info
)
7353 for (info
->num_regsets
= 0;
7354 info
->regsets
[info
->num_regsets
].size
>= 0;
7355 info
->num_regsets
++)
7361 initialize_low (void)
7363 struct sigaction sigchld_action
;
7365 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7366 set_target_ops (the_linux_target
);
7368 linux_ptrace_init_warnings ();
7369 linux_proc_init_warnings ();
7371 sigchld_action
.sa_handler
= sigchld_handler
;
7372 sigemptyset (&sigchld_action
.sa_mask
);
7373 sigchld_action
.sa_flags
= SA_RESTART
;
7374 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7376 initialize_low_arch ();
7378 linux_check_ptrace_features ();