1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2019 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 "common/agent.h"
24 #include "common/rsp-low.h"
25 #include "common/signals-state-save-restore.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
28 #include "common/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 "common/filestuff.h"
47 #include "tracepoint.h"
50 #include "common/common-inferior.h"
51 #include "nat/fork-inferior.h"
52 #include "common/environ.h"
53 #include "common/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"
64 #define SPUFS_MAGIC 0x23c9b64e
67 #ifdef HAVE_PERSONALITY
68 # include <sys/personality.h>
69 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
70 # 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 #ifdef HAVE_LINUX_BTRACE
103 # include "nat/linux-btrace.h"
104 # include "common/btrace-common.h"
107 #ifndef HAVE_ELF32_AUXV_T
108 /* Copied from glibc's elf.h. */
111 uint32_t a_type
; /* Entry type */
114 uint32_t a_val
; /* Integer value */
115 /* We use to have pointer elements added here. We cannot do that,
116 though, since it does not work when using 32-bit definitions
117 on 64-bit platforms and vice versa. */
122 #ifndef HAVE_ELF64_AUXV_T
123 /* Copied from glibc's elf.h. */
126 uint64_t a_type
; /* Entry type */
129 uint64_t a_val
; /* Integer value */
130 /* We use to have pointer elements added here. We cannot do that,
131 though, since it does not work when using 32-bit definitions
132 on 64-bit platforms and vice versa. */
137 /* Does the current host support PTRACE_GETREGSET? */
138 int have_ptrace_getregset
= -1;
142 /* See nat/linux-nat.h. */
145 ptid_of_lwp (struct lwp_info
*lwp
)
147 return ptid_of (get_lwp_thread (lwp
));
150 /* See nat/linux-nat.h. */
153 lwp_set_arch_private_info (struct lwp_info
*lwp
,
154 struct arch_lwp_info
*info
)
156 lwp
->arch_private
= info
;
159 /* See nat/linux-nat.h. */
161 struct arch_lwp_info
*
162 lwp_arch_private_info (struct lwp_info
*lwp
)
164 return lwp
->arch_private
;
167 /* See nat/linux-nat.h. */
170 lwp_is_stopped (struct lwp_info
*lwp
)
175 /* See nat/linux-nat.h. */
177 enum target_stop_reason
178 lwp_stop_reason (struct lwp_info
*lwp
)
180 return lwp
->stop_reason
;
183 /* See nat/linux-nat.h. */
186 lwp_is_stepping (struct lwp_info
*lwp
)
188 return lwp
->stepping
;
191 /* A list of all unknown processes which receive stop signals. Some
192 other process will presumably claim each of these as forked
193 children momentarily. */
195 struct simple_pid_list
197 /* The process ID. */
200 /* The status as reported by waitpid. */
204 struct simple_pid_list
*next
;
206 struct simple_pid_list
*stopped_pids
;
208 /* Trivial list manipulation functions to keep track of a list of new
209 stopped processes. */
212 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
214 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
217 new_pid
->status
= status
;
218 new_pid
->next
= *listp
;
223 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
225 struct simple_pid_list
**p
;
227 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
228 if ((*p
)->pid
== pid
)
230 struct simple_pid_list
*next
= (*p
)->next
;
232 *statusp
= (*p
)->status
;
240 enum stopping_threads_kind
242 /* Not stopping threads presently. */
243 NOT_STOPPING_THREADS
,
245 /* Stopping threads. */
248 /* Stopping and suspending threads. */
249 STOPPING_AND_SUSPENDING_THREADS
252 /* This is set while stop_all_lwps is in effect. */
253 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
255 /* FIXME make into a target method? */
256 int using_threads
= 1;
258 /* True if we're presently stabilizing threads (moving them out of
260 static int stabilizing_threads
;
262 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
263 int step
, int signal
, siginfo_t
*info
);
264 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
265 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
266 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
267 static void unsuspend_all_lwps (struct lwp_info
*except
);
268 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
269 int *wstat
, int options
);
270 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
271 static struct lwp_info
*add_lwp (ptid_t ptid
);
272 static void linux_mourn (struct process_info
*process
);
273 static int linux_stopped_by_watchpoint (void);
274 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
275 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
276 static void proceed_all_lwps (void);
277 static int finish_step_over (struct lwp_info
*lwp
);
278 static int kill_lwp (unsigned long lwpid
, int signo
);
279 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
280 static void complete_ongoing_step_over (void);
281 static int linux_low_ptrace_options (int attached
);
282 static int check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
);
283 static void proceed_one_lwp (thread_info
*thread
, lwp_info
*except
);
285 /* When the event-loop is doing a step-over, this points at the thread
287 ptid_t step_over_bkpt
;
289 /* True if the low target can hardware single-step. */
292 can_hardware_single_step (void)
294 if (the_low_target
.supports_hardware_single_step
!= NULL
)
295 return the_low_target
.supports_hardware_single_step ();
300 /* True if the low target can software single-step. Such targets
301 implement the GET_NEXT_PCS callback. */
304 can_software_single_step (void)
306 return (the_low_target
.get_next_pcs
!= NULL
);
309 /* True if the low target supports memory breakpoints. If so, we'll
310 have a GET_PC implementation. */
313 supports_breakpoints (void)
315 return (the_low_target
.get_pc
!= NULL
);
318 /* Returns true if this target can support fast tracepoints. This
319 does not mean that the in-process agent has been loaded in the
323 supports_fast_tracepoints (void)
325 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
328 /* True if LWP is stopped in its stepping range. */
331 lwp_in_step_range (struct lwp_info
*lwp
)
333 CORE_ADDR pc
= lwp
->stop_pc
;
335 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
338 struct pending_signals
342 struct pending_signals
*prev
;
345 /* The read/write ends of the pipe registered as waitable file in the
347 static int linux_event_pipe
[2] = { -1, -1 };
349 /* True if we're currently in async mode. */
350 #define target_is_async_p() (linux_event_pipe[0] != -1)
352 static void send_sigstop (struct lwp_info
*lwp
);
353 static void wait_for_sigstop (void);
355 /* Return non-zero if HEADER is a 64-bit ELF file. */
358 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
360 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
361 && header
->e_ident
[EI_MAG1
] == ELFMAG1
362 && header
->e_ident
[EI_MAG2
] == ELFMAG2
363 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
365 *machine
= header
->e_machine
;
366 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
373 /* Return non-zero if FILE is a 64-bit ELF file,
374 zero if the file is not a 64-bit ELF file,
375 and -1 if the file is not accessible or doesn't exist. */
378 elf_64_file_p (const char *file
, unsigned int *machine
)
383 fd
= open (file
, O_RDONLY
);
387 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
394 return elf_64_header_p (&header
, machine
);
397 /* Accepts an integer PID; Returns true if the executable PID is
398 running is a 64-bit ELF file.. */
401 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
405 sprintf (file
, "/proc/%d/exe", pid
);
406 return elf_64_file_p (file
, machine
);
410 delete_lwp (struct lwp_info
*lwp
)
412 struct thread_info
*thr
= get_lwp_thread (lwp
);
415 debug_printf ("deleting %ld\n", lwpid_of (thr
));
419 if (the_low_target
.delete_thread
!= NULL
)
420 the_low_target
.delete_thread (lwp
->arch_private
);
422 gdb_assert (lwp
->arch_private
== NULL
);
427 /* Add a process to the common process list, and set its private
430 static struct process_info
*
431 linux_add_process (int pid
, int attached
)
433 struct process_info
*proc
;
435 proc
= add_process (pid
, attached
);
436 proc
->priv
= XCNEW (struct process_info_private
);
438 if (the_low_target
.new_process
!= NULL
)
439 proc
->priv
->arch_private
= the_low_target
.new_process ();
444 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
446 /* Call the target arch_setup function on the current thread. */
449 linux_arch_setup (void)
451 the_low_target
.arch_setup ();
454 /* Call the target arch_setup function on THREAD. */
457 linux_arch_setup_thread (struct thread_info
*thread
)
459 struct thread_info
*saved_thread
;
461 saved_thread
= current_thread
;
462 current_thread
= thread
;
466 current_thread
= saved_thread
;
469 /* Handle a GNU/Linux extended wait response. If we see a clone,
470 fork, or vfork event, we need to add the new LWP to our list
471 (and return 0 so as not to report the trap to higher layers).
472 If we see an exec event, we will modify ORIG_EVENT_LWP to point
473 to a new LWP representing the new program. */
476 handle_extended_wait (struct lwp_info
**orig_event_lwp
, int wstat
)
478 client_state
&cs
= get_client_state ();
479 struct lwp_info
*event_lwp
= *orig_event_lwp
;
480 int event
= linux_ptrace_get_extended_event (wstat
);
481 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
482 struct lwp_info
*new_lwp
;
484 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
486 /* All extended events we currently use are mid-syscall. Only
487 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
488 you have to be using PTRACE_SEIZE to get that. */
489 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
491 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
492 || (event
== PTRACE_EVENT_CLONE
))
495 unsigned long new_pid
;
498 /* Get the pid of the new lwp. */
499 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
502 /* If we haven't already seen the new PID stop, wait for it now. */
503 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
505 /* The new child has a pending SIGSTOP. We can't affect it until it
506 hits the SIGSTOP, but we're already attached. */
508 ret
= my_waitpid (new_pid
, &status
, __WALL
);
511 perror_with_name ("waiting for new child");
512 else if (ret
!= new_pid
)
513 warning ("wait returned unexpected PID %d", ret
);
514 else if (!WIFSTOPPED (status
))
515 warning ("wait returned unexpected status 0x%x", status
);
518 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
520 struct process_info
*parent_proc
;
521 struct process_info
*child_proc
;
522 struct lwp_info
*child_lwp
;
523 struct thread_info
*child_thr
;
524 struct target_desc
*tdesc
;
526 ptid
= ptid_t (new_pid
, new_pid
, 0);
530 debug_printf ("HEW: Got fork event from LWP %ld, "
532 ptid_of (event_thr
).lwp (),
536 /* Add the new process to the tables and clone the breakpoint
537 lists of the parent. We need to do this even if the new process
538 will be detached, since we will need the process object and the
539 breakpoints to remove any breakpoints from memory when we
540 detach, and the client side will access registers. */
541 child_proc
= linux_add_process (new_pid
, 0);
542 gdb_assert (child_proc
!= NULL
);
543 child_lwp
= add_lwp (ptid
);
544 gdb_assert (child_lwp
!= NULL
);
545 child_lwp
->stopped
= 1;
546 child_lwp
->must_set_ptrace_flags
= 1;
547 child_lwp
->status_pending_p
= 0;
548 child_thr
= get_lwp_thread (child_lwp
);
549 child_thr
->last_resume_kind
= resume_stop
;
550 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
552 /* If we're suspending all threads, leave this one suspended
553 too. If the fork/clone parent is stepping over a breakpoint,
554 all other threads have been suspended already. Leave the
555 child suspended too. */
556 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
557 || event_lwp
->bp_reinsert
!= 0)
560 debug_printf ("HEW: leaving child suspended\n");
561 child_lwp
->suspended
= 1;
564 parent_proc
= get_thread_process (event_thr
);
565 child_proc
->attached
= parent_proc
->attached
;
567 if (event_lwp
->bp_reinsert
!= 0
568 && can_software_single_step ()
569 && event
== PTRACE_EVENT_VFORK
)
571 /* If we leave single-step breakpoints there, child will
572 hit it, so uninsert single-step breakpoints from parent
573 (and child). Once vfork child is done, reinsert
574 them back to parent. */
575 uninsert_single_step_breakpoints (event_thr
);
578 clone_all_breakpoints (child_thr
, event_thr
);
580 tdesc
= allocate_target_description ();
581 copy_target_description (tdesc
, parent_proc
->tdesc
);
582 child_proc
->tdesc
= tdesc
;
584 /* Clone arch-specific process data. */
585 if (the_low_target
.new_fork
!= NULL
)
586 the_low_target
.new_fork (parent_proc
, child_proc
);
588 /* Save fork info in the parent thread. */
589 if (event
== PTRACE_EVENT_FORK
)
590 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
591 else if (event
== PTRACE_EVENT_VFORK
)
592 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
594 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
596 /* The status_pending field contains bits denoting the
597 extended event, so when the pending event is handled,
598 the handler will look at lwp->waitstatus. */
599 event_lwp
->status_pending_p
= 1;
600 event_lwp
->status_pending
= wstat
;
602 /* Link the threads until the parent event is passed on to
604 event_lwp
->fork_relative
= child_lwp
;
605 child_lwp
->fork_relative
= event_lwp
;
607 /* If the parent thread is doing step-over with single-step
608 breakpoints, the list of single-step breakpoints are cloned
609 from the parent's. Remove them from the child process.
610 In case of vfork, we'll reinsert them back once vforked
612 if (event_lwp
->bp_reinsert
!= 0
613 && can_software_single_step ())
615 /* The child process is forked and stopped, so it is safe
616 to access its memory without stopping all other threads
617 from other processes. */
618 delete_single_step_breakpoints (child_thr
);
620 gdb_assert (has_single_step_breakpoints (event_thr
));
621 gdb_assert (!has_single_step_breakpoints (child_thr
));
624 /* Report the event. */
629 debug_printf ("HEW: Got clone event "
630 "from LWP %ld, new child is LWP %ld\n",
631 lwpid_of (event_thr
), new_pid
);
633 ptid
= ptid_t (pid_of (event_thr
), new_pid
, 0);
634 new_lwp
= add_lwp (ptid
);
636 /* Either we're going to immediately resume the new thread
637 or leave it stopped. linux_resume_one_lwp is a nop if it
638 thinks the thread is currently running, so set this first
639 before calling linux_resume_one_lwp. */
640 new_lwp
->stopped
= 1;
642 /* If we're suspending all threads, leave this one suspended
643 too. If the fork/clone parent is stepping over a breakpoint,
644 all other threads have been suspended already. Leave the
645 child suspended too. */
646 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
647 || event_lwp
->bp_reinsert
!= 0)
648 new_lwp
->suspended
= 1;
650 /* Normally we will get the pending SIGSTOP. But in some cases
651 we might get another signal delivered to the group first.
652 If we do get another signal, be sure not to lose it. */
653 if (WSTOPSIG (status
) != SIGSTOP
)
655 new_lwp
->stop_expected
= 1;
656 new_lwp
->status_pending_p
= 1;
657 new_lwp
->status_pending
= status
;
659 else if (cs
.report_thread_events
)
661 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
662 new_lwp
->status_pending_p
= 1;
663 new_lwp
->status_pending
= status
;
667 thread_db_notice_clone (event_thr
, ptid
);
670 /* Don't report the event. */
673 else if (event
== PTRACE_EVENT_VFORK_DONE
)
675 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
677 if (event_lwp
->bp_reinsert
!= 0 && can_software_single_step ())
679 reinsert_single_step_breakpoints (event_thr
);
681 gdb_assert (has_single_step_breakpoints (event_thr
));
684 /* Report the event. */
687 else if (event
== PTRACE_EVENT_EXEC
&& cs
.report_exec_events
)
689 struct process_info
*proc
;
690 std::vector
<int> syscalls_to_catch
;
696 debug_printf ("HEW: Got exec event from LWP %ld\n",
697 lwpid_of (event_thr
));
700 /* Get the event ptid. */
701 event_ptid
= ptid_of (event_thr
);
702 event_pid
= event_ptid
.pid ();
704 /* Save the syscall list from the execing process. */
705 proc
= get_thread_process (event_thr
);
706 syscalls_to_catch
= std::move (proc
->syscalls_to_catch
);
708 /* Delete the execing process and all its threads. */
710 current_thread
= NULL
;
712 /* Create a new process/lwp/thread. */
713 proc
= linux_add_process (event_pid
, 0);
714 event_lwp
= add_lwp (event_ptid
);
715 event_thr
= get_lwp_thread (event_lwp
);
716 gdb_assert (current_thread
== event_thr
);
717 linux_arch_setup_thread (event_thr
);
719 /* Set the event status. */
720 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
721 event_lwp
->waitstatus
.value
.execd_pathname
722 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
724 /* Mark the exec status as pending. */
725 event_lwp
->stopped
= 1;
726 event_lwp
->status_pending_p
= 1;
727 event_lwp
->status_pending
= wstat
;
728 event_thr
->last_resume_kind
= resume_continue
;
729 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
731 /* Update syscall state in the new lwp, effectively mid-syscall too. */
732 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
734 /* Restore the list to catch. Don't rely on the client, which is free
735 to avoid sending a new list when the architecture doesn't change.
736 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
737 proc
->syscalls_to_catch
= std::move (syscalls_to_catch
);
739 /* Report the event. */
740 *orig_event_lwp
= event_lwp
;
744 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
747 /* Return the PC as read from the regcache of LWP, without any
751 get_pc (struct lwp_info
*lwp
)
753 struct thread_info
*saved_thread
;
754 struct regcache
*regcache
;
757 if (the_low_target
.get_pc
== NULL
)
760 saved_thread
= current_thread
;
761 current_thread
= get_lwp_thread (lwp
);
763 regcache
= get_thread_regcache (current_thread
, 1);
764 pc
= (*the_low_target
.get_pc
) (regcache
);
767 debug_printf ("pc is 0x%lx\n", (long) pc
);
769 current_thread
= saved_thread
;
773 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
774 Fill *SYSNO with the syscall nr trapped. */
777 get_syscall_trapinfo (struct lwp_info
*lwp
, int *sysno
)
779 struct thread_info
*saved_thread
;
780 struct regcache
*regcache
;
782 if (the_low_target
.get_syscall_trapinfo
== NULL
)
784 /* If we cannot get the syscall trapinfo, report an unknown
785 system call number. */
786 *sysno
= UNKNOWN_SYSCALL
;
790 saved_thread
= current_thread
;
791 current_thread
= get_lwp_thread (lwp
);
793 regcache
= get_thread_regcache (current_thread
, 1);
794 (*the_low_target
.get_syscall_trapinfo
) (regcache
, sysno
);
797 debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno
);
799 current_thread
= saved_thread
;
802 static int check_stopped_by_watchpoint (struct lwp_info
*child
);
804 /* Called when the LWP stopped for a signal/trap. If it stopped for a
805 trap check what caused it (breakpoint, watchpoint, trace, etc.),
806 and save the result in the LWP's stop_reason field. If it stopped
807 for a breakpoint, decrement the PC if necessary on the lwp's
808 architecture. Returns true if we now have the LWP's stop PC. */
811 save_stop_reason (struct lwp_info
*lwp
)
814 CORE_ADDR sw_breakpoint_pc
;
815 struct thread_info
*saved_thread
;
816 #if USE_SIGTRAP_SIGINFO
820 if (the_low_target
.get_pc
== NULL
)
824 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
826 /* breakpoint_at reads from the current thread. */
827 saved_thread
= current_thread
;
828 current_thread
= get_lwp_thread (lwp
);
830 #if USE_SIGTRAP_SIGINFO
831 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
832 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
834 if (siginfo
.si_signo
== SIGTRAP
)
836 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
837 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
839 /* The si_code is ambiguous on this arch -- check debug
841 if (!check_stopped_by_watchpoint (lwp
))
842 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
844 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
846 /* If we determine the LWP stopped for a SW breakpoint,
847 trust it. Particularly don't check watchpoint
848 registers, because at least on s390, we'd find
849 stopped-by-watchpoint as long as there's a watchpoint
851 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
853 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
855 /* This can indicate either a hardware breakpoint or
856 hardware watchpoint. Check debug registers. */
857 if (!check_stopped_by_watchpoint (lwp
))
858 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
860 else if (siginfo
.si_code
== TRAP_TRACE
)
862 /* We may have single stepped an instruction that
863 triggered a watchpoint. In that case, on some
864 architectures (such as x86), instead of TRAP_HWBKPT,
865 si_code indicates TRAP_TRACE, and we need to check
866 the debug registers separately. */
867 if (!check_stopped_by_watchpoint (lwp
))
868 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
873 /* We may have just stepped a breakpoint instruction. E.g., in
874 non-stop mode, GDB first tells the thread A to step a range, and
875 then the user inserts a breakpoint inside the range. In that
876 case we need to report the breakpoint PC. */
877 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
878 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
879 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
881 if (hardware_breakpoint_inserted_here (pc
))
882 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
884 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
885 check_stopped_by_watchpoint (lwp
);
888 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
892 struct thread_info
*thr
= get_lwp_thread (lwp
);
894 debug_printf ("CSBB: %s stopped by software breakpoint\n",
895 target_pid_to_str (ptid_of (thr
)));
898 /* Back up the PC if necessary. */
899 if (pc
!= sw_breakpoint_pc
)
901 struct regcache
*regcache
902 = get_thread_regcache (current_thread
, 1);
903 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
906 /* Update this so we record the correct stop PC below. */
907 pc
= sw_breakpoint_pc
;
909 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
913 struct thread_info
*thr
= get_lwp_thread (lwp
);
915 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
916 target_pid_to_str (ptid_of (thr
)));
919 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
923 struct thread_info
*thr
= get_lwp_thread (lwp
);
925 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
926 target_pid_to_str (ptid_of (thr
)));
929 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
933 struct thread_info
*thr
= get_lwp_thread (lwp
);
935 debug_printf ("CSBB: %s stopped by trace\n",
936 target_pid_to_str (ptid_of (thr
)));
941 current_thread
= saved_thread
;
945 static struct lwp_info
*
946 add_lwp (ptid_t ptid
)
948 struct lwp_info
*lwp
;
950 lwp
= XCNEW (struct lwp_info
);
952 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
954 lwp
->thread
= add_thread (ptid
, lwp
);
956 if (the_low_target
.new_thread
!= NULL
)
957 the_low_target
.new_thread (lwp
);
962 /* Callback to be used when calling fork_inferior, responsible for
963 actually initiating the tracing of the inferior. */
968 if (ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0,
969 (PTRACE_TYPE_ARG4
) 0) < 0)
970 trace_start_error_with_name ("ptrace");
972 if (setpgid (0, 0) < 0)
973 trace_start_error_with_name ("setpgid");
975 /* If GDBserver is connected to gdb via stdio, redirect the inferior's
976 stdout to stderr so that inferior i/o doesn't corrupt the connection.
977 Also, redirect stdin to /dev/null. */
978 if (remote_connection_is_stdio ())
981 trace_start_error_with_name ("close");
982 if (open ("/dev/null", O_RDONLY
) < 0)
983 trace_start_error_with_name ("open");
985 trace_start_error_with_name ("dup2");
986 if (write (2, "stdin/stdout redirected\n",
987 sizeof ("stdin/stdout redirected\n") - 1) < 0)
989 /* Errors ignored. */;
994 /* Start an inferior process and returns its pid.
995 PROGRAM is the name of the program to be started, and PROGRAM_ARGS
996 are its arguments. */
999 linux_create_inferior (const char *program
,
1000 const std::vector
<char *> &program_args
)
1002 client_state
&cs
= get_client_state ();
1003 struct lwp_info
*new_lwp
;
1008 maybe_disable_address_space_randomization restore_personality
1009 (cs
.disable_randomization
);
1010 std::string str_program_args
= stringify_argv (program_args
);
1012 pid
= fork_inferior (program
,
1013 str_program_args
.c_str (),
1014 get_environ ()->envp (), linux_ptrace_fun
,
1015 NULL
, NULL
, NULL
, NULL
);
1018 linux_add_process (pid
, 0);
1020 ptid
= ptid_t (pid
, pid
, 0);
1021 new_lwp
= add_lwp (ptid
);
1022 new_lwp
->must_set_ptrace_flags
= 1;
1024 post_fork_inferior (pid
, program
);
1029 /* Implement the post_create_inferior target_ops method. */
1032 linux_post_create_inferior (void)
1034 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
1036 linux_arch_setup ();
1038 if (lwp
->must_set_ptrace_flags
)
1040 struct process_info
*proc
= current_process ();
1041 int options
= linux_low_ptrace_options (proc
->attached
);
1043 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
1044 lwp
->must_set_ptrace_flags
= 0;
1048 /* Attach to an inferior process. Returns 0 on success, ERRNO on
1052 linux_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
= linux_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
, 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_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
= linux_add_process (pid
, 1);
1193 /* Attach to PID. We will check for other threads
1195 err
= linux_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
= linux_wait_for_event_filtered (pid_ptid
, pid_ptid
,
1234 gdb_assert (lwpid
> 0);
1236 lwp
= find_lwp_pid (ptid_t (lwpid
));
1238 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1240 lwp
->status_pending_p
= 1;
1241 lwp
->status_pending
= wstat
;
1244 initial_thread
->last_resume_kind
= resume_continue
;
1248 gdb_assert (proc
->tdesc
!= NULL
);
1255 last_thread_of_process_p (int pid
)
1257 bool seen_one
= false;
1259 thread_info
*thread
= find_thread (pid
, [&] (thread_info
*thr_arg
)
1263 /* This is the first thread of this process we see. */
1269 /* This is the second thread of this process we see. */
1274 return thread
== NULL
;
1280 linux_kill_one_lwp (struct lwp_info
*lwp
)
1282 struct thread_info
*thr
= get_lwp_thread (lwp
);
1283 int pid
= lwpid_of (thr
);
1285 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1286 there is no signal context, and ptrace(PTRACE_KILL) (or
1287 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1288 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1289 alternative is to kill with SIGKILL. We only need one SIGKILL
1290 per process, not one for each thread. But since we still support
1291 support debugging programs using raw clone without CLONE_THREAD,
1292 we send one for each thread. For years, we used PTRACE_KILL
1293 only, so we're being a bit paranoid about some old kernels where
1294 PTRACE_KILL might work better (dubious if there are any such, but
1295 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1296 second, and so we're fine everywhere. */
1299 kill_lwp (pid
, SIGKILL
);
1302 int save_errno
= errno
;
1304 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1305 target_pid_to_str (ptid_of (thr
)),
1306 save_errno
? strerror (save_errno
) : "OK");
1310 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1313 int save_errno
= errno
;
1315 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1316 target_pid_to_str (ptid_of (thr
)),
1317 save_errno
? strerror (save_errno
) : "OK");
1321 /* Kill LWP and wait for it to die. */
1324 kill_wait_lwp (struct lwp_info
*lwp
)
1326 struct thread_info
*thr
= get_lwp_thread (lwp
);
1327 int pid
= ptid_of (thr
).pid ();
1328 int lwpid
= ptid_of (thr
).lwp ();
1333 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1337 linux_kill_one_lwp (lwp
);
1339 /* Make sure it died. Notes:
1341 - The loop is most likely unnecessary.
1343 - We don't use linux_wait_for_event as that could delete lwps
1344 while we're iterating over them. We're not interested in
1345 any pending status at this point, only in making sure all
1346 wait status on the kernel side are collected until the
1349 - We don't use __WALL here as the __WALL emulation relies on
1350 SIGCHLD, and killing a stopped process doesn't generate
1351 one, nor an exit status.
1353 res
= my_waitpid (lwpid
, &wstat
, 0);
1354 if (res
== -1 && errno
== ECHILD
)
1355 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1356 } while (res
> 0 && WIFSTOPPED (wstat
));
1358 /* Even if it was stopped, the child may have already disappeared.
1359 E.g., if it was killed by SIGKILL. */
1360 if (res
< 0 && errno
!= ECHILD
)
1361 perror_with_name ("kill_wait_lwp");
1364 /* Callback for `for_each_thread'. Kills an lwp of a given process,
1365 except the leader. */
1368 kill_one_lwp_callback (thread_info
*thread
, int pid
)
1370 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1372 /* We avoid killing the first thread here, because of a Linux kernel (at
1373 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1374 the children get a chance to be reaped, it will remain a zombie
1377 if (lwpid_of (thread
) == pid
)
1380 debug_printf ("lkop: is last of process %s\n",
1381 target_pid_to_str (thread
->id
));
1385 kill_wait_lwp (lwp
);
1389 linux_kill (process_info
*process
)
1391 int pid
= process
->pid
;
1393 /* If we're killing a running inferior, make sure it is stopped
1394 first, as PTRACE_KILL will not work otherwise. */
1395 stop_all_lwps (0, NULL
);
1397 for_each_thread (pid
, [&] (thread_info
*thread
)
1399 kill_one_lwp_callback (thread
, pid
);
1402 /* See the comment in linux_kill_one_lwp. We did not kill the first
1403 thread in the list, so do so now. */
1404 lwp_info
*lwp
= find_lwp_pid (ptid_t (pid
));
1409 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1413 kill_wait_lwp (lwp
);
1415 the_target
->mourn (process
);
1417 /* Since we presently can only stop all lwps of all processes, we
1418 need to unstop lwps of other processes. */
1419 unstop_all_lwps (0, NULL
);
1423 /* Get pending signal of THREAD, for detaching purposes. This is the
1424 signal the thread last stopped for, which we need to deliver to the
1425 thread when detaching, otherwise, it'd be suppressed/lost. */
1428 get_detach_signal (struct thread_info
*thread
)
1430 client_state
&cs
= get_client_state ();
1431 enum gdb_signal signo
= GDB_SIGNAL_0
;
1433 struct lwp_info
*lp
= get_thread_lwp (thread
);
1435 if (lp
->status_pending_p
)
1436 status
= lp
->status_pending
;
1439 /* If the thread had been suspended by gdbserver, and it stopped
1440 cleanly, then it'll have stopped with SIGSTOP. But we don't
1441 want to deliver that SIGSTOP. */
1442 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1443 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1446 /* Otherwise, we may need to deliver the signal we
1448 status
= lp
->last_status
;
1451 if (!WIFSTOPPED (status
))
1454 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1455 target_pid_to_str (ptid_of (thread
)));
1459 /* Extended wait statuses aren't real SIGTRAPs. */
1460 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1463 debug_printf ("GPS: lwp %s had stopped with extended "
1464 "status: no pending signal\n",
1465 target_pid_to_str (ptid_of (thread
)));
1469 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1471 if (cs
.program_signals_p
&& !cs
.program_signals
[signo
])
1474 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1475 target_pid_to_str (ptid_of (thread
)),
1476 gdb_signal_to_string (signo
));
1479 else if (!cs
.program_signals_p
1480 /* If we have no way to know which signals GDB does not
1481 want to have passed to the program, assume
1482 SIGTRAP/SIGINT, which is GDB's default. */
1483 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1486 debug_printf ("GPS: lwp %s had signal %s, "
1487 "but we don't know if we should pass it. "
1488 "Default to not.\n",
1489 target_pid_to_str (ptid_of (thread
)),
1490 gdb_signal_to_string (signo
));
1496 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1497 target_pid_to_str (ptid_of (thread
)),
1498 gdb_signal_to_string (signo
));
1500 return WSTOPSIG (status
);
1504 /* Detach from LWP. */
1507 linux_detach_one_lwp (struct lwp_info
*lwp
)
1509 struct thread_info
*thread
= get_lwp_thread (lwp
);
1513 /* If there is a pending SIGSTOP, get rid of it. */
1514 if (lwp
->stop_expected
)
1517 debug_printf ("Sending SIGCONT to %s\n",
1518 target_pid_to_str (ptid_of (thread
)));
1520 kill_lwp (lwpid_of (thread
), SIGCONT
);
1521 lwp
->stop_expected
= 0;
1524 /* Pass on any pending signal for this thread. */
1525 sig
= get_detach_signal (thread
);
1527 /* Preparing to resume may try to write registers, and fail if the
1528 lwp is zombie. If that happens, ignore the error. We'll handle
1529 it below, when detach fails with ESRCH. */
1532 /* Flush any pending changes to the process's registers. */
1533 regcache_invalidate_thread (thread
);
1535 /* Finally, let it resume. */
1536 if (the_low_target
.prepare_to_resume
!= NULL
)
1537 the_low_target
.prepare_to_resume (lwp
);
1539 CATCH (ex
, RETURN_MASK_ERROR
)
1541 if (!check_ptrace_stopped_lwp_gone (lwp
))
1542 throw_exception (ex
);
1546 lwpid
= lwpid_of (thread
);
1547 if (ptrace (PTRACE_DETACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0,
1548 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1550 int save_errno
= errno
;
1552 /* We know the thread exists, so ESRCH must mean the lwp is
1553 zombie. This can happen if one of the already-detached
1554 threads exits the whole thread group. In that case we're
1555 still attached, and must reap the lwp. */
1556 if (save_errno
== ESRCH
)
1560 ret
= my_waitpid (lwpid
, &status
, __WALL
);
1563 warning (_("Couldn't reap LWP %d while detaching: %s"),
1564 lwpid
, strerror (errno
));
1566 else if (!WIFEXITED (status
) && !WIFSIGNALED (status
))
1568 warning (_("Reaping LWP %d while detaching "
1569 "returned unexpected status 0x%x"),
1575 error (_("Can't detach %s: %s"),
1576 target_pid_to_str (ptid_of (thread
)),
1577 strerror (save_errno
));
1580 else if (debug_threads
)
1582 debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
1583 target_pid_to_str (ptid_of (thread
)),
1590 /* Callback for for_each_thread. Detaches from non-leader threads of a
1594 linux_detach_lwp_callback (thread_info
*thread
)
1596 /* We don't actually detach from the thread group leader just yet.
1597 If the thread group exits, we must reap the zombie clone lwps
1598 before we're able to reap the leader. */
1599 if (thread
->id
.pid () == thread
->id
.lwp ())
1602 lwp_info
*lwp
= get_thread_lwp (thread
);
1603 linux_detach_one_lwp (lwp
);
1607 linux_detach (process_info
*process
)
1609 struct lwp_info
*main_lwp
;
1611 /* As there's a step over already in progress, let it finish first,
1612 otherwise nesting a stabilize_threads operation on top gets real
1614 complete_ongoing_step_over ();
1616 /* Stop all threads before detaching. First, ptrace requires that
1617 the thread is stopped to sucessfully detach. Second, thread_db
1618 may need to uninstall thread event breakpoints from memory, which
1619 only works with a stopped process anyway. */
1620 stop_all_lwps (0, NULL
);
1622 #ifdef USE_THREAD_DB
1623 thread_db_detach (process
);
1626 /* Stabilize threads (move out of jump pads). */
1627 stabilize_threads ();
1629 /* Detach from the clone lwps first. If the thread group exits just
1630 while we're detaching, we must reap the clone lwps before we're
1631 able to reap the leader. */
1632 for_each_thread (process
->pid
, linux_detach_lwp_callback
);
1634 main_lwp
= find_lwp_pid (ptid_t (process
->pid
));
1635 linux_detach_one_lwp (main_lwp
);
1637 the_target
->mourn (process
);
1639 /* Since we presently can only stop all lwps of all processes, we
1640 need to unstop lwps of other processes. */
1641 unstop_all_lwps (0, NULL
);
1645 /* Remove all LWPs that belong to process PROC from the lwp list. */
1648 linux_mourn (struct process_info
*process
)
1650 struct process_info_private
*priv
;
1652 #ifdef USE_THREAD_DB
1653 thread_db_mourn (process
);
1656 for_each_thread (process
->pid
, [] (thread_info
*thread
)
1658 delete_lwp (get_thread_lwp (thread
));
1661 /* Freeing all private data. */
1662 priv
= process
->priv
;
1663 if (the_low_target
.delete_process
!= NULL
)
1664 the_low_target
.delete_process (priv
->arch_private
);
1666 gdb_assert (priv
->arch_private
== NULL
);
1668 process
->priv
= NULL
;
1670 remove_process (process
);
1674 linux_join (int pid
)
1679 ret
= my_waitpid (pid
, &status
, 0);
1680 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1682 } while (ret
!= -1 || errno
!= ECHILD
);
1685 /* Return nonzero if the given thread is still alive. */
1687 linux_thread_alive (ptid_t ptid
)
1689 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1691 /* We assume we always know if a thread exits. If a whole process
1692 exited but we still haven't been able to report it to GDB, we'll
1693 hold on to the last lwp of the dead process. */
1695 return !lwp_is_marked_dead (lwp
);
1700 /* Return 1 if this lwp still has an interesting status pending. If
1701 not (e.g., it had stopped for a breakpoint that is gone), return
1705 thread_still_has_status_pending_p (struct thread_info
*thread
)
1707 struct lwp_info
*lp
= get_thread_lwp (thread
);
1709 if (!lp
->status_pending_p
)
1712 if (thread
->last_resume_kind
!= resume_stop
1713 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1714 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1716 struct thread_info
*saved_thread
;
1720 gdb_assert (lp
->last_status
!= 0);
1724 saved_thread
= current_thread
;
1725 current_thread
= thread
;
1727 if (pc
!= lp
->stop_pc
)
1730 debug_printf ("PC of %ld changed\n",
1735 #if !USE_SIGTRAP_SIGINFO
1736 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1737 && !(*the_low_target
.breakpoint_at
) (pc
))
1740 debug_printf ("previous SW breakpoint of %ld gone\n",
1744 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1745 && !hardware_breakpoint_inserted_here (pc
))
1748 debug_printf ("previous HW breakpoint of %ld gone\n",
1754 current_thread
= saved_thread
;
1759 debug_printf ("discarding pending breakpoint status\n");
1760 lp
->status_pending_p
= 0;
1768 /* Returns true if LWP is resumed from the client's perspective. */
1771 lwp_resumed (struct lwp_info
*lwp
)
1773 struct thread_info
*thread
= get_lwp_thread (lwp
);
1775 if (thread
->last_resume_kind
!= resume_stop
)
1778 /* Did gdb send us a `vCont;t', but we haven't reported the
1779 corresponding stop to gdb yet? If so, the thread is still
1780 resumed/running from gdb's perspective. */
1781 if (thread
->last_resume_kind
== resume_stop
1782 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1788 /* Return true if this lwp has an interesting status pending. */
1790 status_pending_p_callback (thread_info
*thread
, ptid_t ptid
)
1792 struct lwp_info
*lp
= get_thread_lwp (thread
);
1794 /* Check if we're only interested in events from a specific process
1795 or a specific LWP. */
1796 if (!thread
->id
.matches (ptid
))
1799 if (!lwp_resumed (lp
))
1802 if (lp
->status_pending_p
1803 && !thread_still_has_status_pending_p (thread
))
1805 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1809 return lp
->status_pending_p
;
1813 find_lwp_pid (ptid_t ptid
)
1815 thread_info
*thread
= find_thread ([&] (thread_info
*thr_arg
)
1817 int lwp
= ptid
.lwp () != 0 ? ptid
.lwp () : ptid
.pid ();
1818 return thr_arg
->id
.lwp () == lwp
;
1824 return get_thread_lwp (thread
);
1827 /* Return the number of known LWPs in the tgid given by PID. */
1834 for_each_thread (pid
, [&] (thread_info
*thread
)
1842 /* See nat/linux-nat.h. */
1845 iterate_over_lwps (ptid_t filter
,
1846 iterate_over_lwps_ftype callback
,
1849 thread_info
*thread
= find_thread (filter
, [&] (thread_info
*thr_arg
)
1851 lwp_info
*lwp
= get_thread_lwp (thr_arg
);
1853 return callback (lwp
, data
);
1859 return get_thread_lwp (thread
);
1862 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1863 their exits until all other threads in the group have exited. */
1866 check_zombie_leaders (void)
1868 for_each_process ([] (process_info
*proc
) {
1869 pid_t leader_pid
= pid_of (proc
);
1870 struct lwp_info
*leader_lp
;
1872 leader_lp
= find_lwp_pid (ptid_t (leader_pid
));
1875 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1876 "num_lwps=%d, zombie=%d\n",
1877 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1878 linux_proc_pid_is_zombie (leader_pid
));
1880 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1881 /* Check if there are other threads in the group, as we may
1882 have raced with the inferior simply exiting. */
1883 && !last_thread_of_process_p (leader_pid
)
1884 && linux_proc_pid_is_zombie (leader_pid
))
1886 /* A leader zombie can mean one of two things:
1888 - It exited, and there's an exit status pending
1889 available, or only the leader exited (not the whole
1890 program). In the latter case, we can't waitpid the
1891 leader's exit status until all other threads are gone.
1893 - There are 3 or more threads in the group, and a thread
1894 other than the leader exec'd. On an exec, the Linux
1895 kernel destroys all other threads (except the execing
1896 one) in the thread group, and resets the execing thread's
1897 tid to the tgid. No exit notification is sent for the
1898 execing thread -- from the ptracer's perspective, it
1899 appears as though the execing thread just vanishes.
1900 Until we reap all other threads except the leader and the
1901 execing thread, the leader will be zombie, and the
1902 execing thread will be in `D (disc sleep)'. As soon as
1903 all other threads are reaped, the execing thread changes
1904 it's tid to the tgid, and the previous (zombie) leader
1905 vanishes, giving place to the "new" leader. We could try
1906 distinguishing the exit and exec cases, by waiting once
1907 more, and seeing if something comes out, but it doesn't
1908 sound useful. The previous leader _does_ go away, and
1909 we'll re-add the new one once we see the exec event
1910 (which is just the same as what would happen if the
1911 previous leader did exit voluntarily before some other
1915 debug_printf ("CZL: Thread group leader %d zombie "
1916 "(it exited, or another thread execd).\n",
1919 delete_lwp (leader_lp
);
1924 /* Callback for `find_thread'. Returns the first LWP that is not
1928 not_stopped_callback (thread_info
*thread
, ptid_t filter
)
1930 if (!thread
->id
.matches (filter
))
1933 lwp_info
*lwp
= get_thread_lwp (thread
);
1935 return !lwp
->stopped
;
1938 /* Increment LWP's suspend count. */
1941 lwp_suspended_inc (struct lwp_info
*lwp
)
1945 if (debug_threads
&& lwp
->suspended
> 4)
1947 struct thread_info
*thread
= get_lwp_thread (lwp
);
1949 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1950 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1954 /* Decrement LWP's suspend count. */
1957 lwp_suspended_decr (struct lwp_info
*lwp
)
1961 if (lwp
->suspended
< 0)
1963 struct thread_info
*thread
= get_lwp_thread (lwp
);
1965 internal_error (__FILE__
, __LINE__
,
1966 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1971 /* This function should only be called if the LWP got a SIGTRAP.
1973 Handle any tracepoint steps or hits. Return true if a tracepoint
1974 event was handled, 0 otherwise. */
1977 handle_tracepoints (struct lwp_info
*lwp
)
1979 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1980 int tpoint_related_event
= 0;
1982 gdb_assert (lwp
->suspended
== 0);
1984 /* If this tracepoint hit causes a tracing stop, we'll immediately
1985 uninsert tracepoints. To do this, we temporarily pause all
1986 threads, unpatch away, and then unpause threads. We need to make
1987 sure the unpausing doesn't resume LWP too. */
1988 lwp_suspended_inc (lwp
);
1990 /* And we need to be sure that any all-threads-stopping doesn't try
1991 to move threads out of the jump pads, as it could deadlock the
1992 inferior (LWP could be in the jump pad, maybe even holding the
1995 /* Do any necessary step collect actions. */
1996 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1998 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
2000 /* See if we just hit a tracepoint and do its main collect
2002 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
2004 lwp_suspended_decr (lwp
);
2006 gdb_assert (lwp
->suspended
== 0);
2007 gdb_assert (!stabilizing_threads
2008 || (lwp
->collecting_fast_tracepoint
2009 != fast_tpoint_collect_result::not_collecting
));
2011 if (tpoint_related_event
)
2014 debug_printf ("got a tracepoint event\n");
2021 /* Convenience wrapper. Returns information about LWP's fast tracepoint
2022 collection status. */
2024 static fast_tpoint_collect_result
2025 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
2026 struct fast_tpoint_collect_status
*status
)
2028 CORE_ADDR thread_area
;
2029 struct thread_info
*thread
= get_lwp_thread (lwp
);
2031 if (the_low_target
.get_thread_area
== NULL
)
2032 return fast_tpoint_collect_result::not_collecting
;
2034 /* Get the thread area address. This is used to recognize which
2035 thread is which when tracing with the in-process agent library.
2036 We don't read anything from the address, and treat it as opaque;
2037 it's the address itself that we assume is unique per-thread. */
2038 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
2039 return fast_tpoint_collect_result::not_collecting
;
2041 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
2044 /* The reason we resume in the caller, is because we want to be able
2045 to pass lwp->status_pending as WSTAT, and we need to clear
2046 status_pending_p before resuming, otherwise, linux_resume_one_lwp
2047 refuses to resume. */
2050 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
2052 struct thread_info
*saved_thread
;
2054 saved_thread
= current_thread
;
2055 current_thread
= get_lwp_thread (lwp
);
2058 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
2059 && supports_fast_tracepoints ()
2060 && agent_loaded_p ())
2062 struct fast_tpoint_collect_status status
;
2065 debug_printf ("Checking whether LWP %ld needs to move out of the "
2067 lwpid_of (current_thread
));
2069 fast_tpoint_collect_result r
2070 = linux_fast_tracepoint_collecting (lwp
, &status
);
2073 || (WSTOPSIG (*wstat
) != SIGILL
2074 && WSTOPSIG (*wstat
) != SIGFPE
2075 && WSTOPSIG (*wstat
) != SIGSEGV
2076 && WSTOPSIG (*wstat
) != SIGBUS
))
2078 lwp
->collecting_fast_tracepoint
= r
;
2080 if (r
!= fast_tpoint_collect_result::not_collecting
)
2082 if (r
== fast_tpoint_collect_result::before_insn
2083 && lwp
->exit_jump_pad_bkpt
== NULL
)
2085 /* Haven't executed the original instruction yet.
2086 Set breakpoint there, and wait till it's hit,
2087 then single-step until exiting the jump pad. */
2088 lwp
->exit_jump_pad_bkpt
2089 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2093 debug_printf ("Checking whether LWP %ld needs to move out of "
2094 "the jump pad...it does\n",
2095 lwpid_of (current_thread
));
2096 current_thread
= saved_thread
;
2103 /* If we get a synchronous signal while collecting, *and*
2104 while executing the (relocated) original instruction,
2105 reset the PC to point at the tpoint address, before
2106 reporting to GDB. Otherwise, it's an IPA lib bug: just
2107 report the signal to GDB, and pray for the best. */
2109 lwp
->collecting_fast_tracepoint
2110 = fast_tpoint_collect_result::not_collecting
;
2112 if (r
!= fast_tpoint_collect_result::not_collecting
2113 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2114 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2117 struct regcache
*regcache
;
2119 /* The si_addr on a few signals references the address
2120 of the faulting instruction. Adjust that as
2122 if ((WSTOPSIG (*wstat
) == SIGILL
2123 || WSTOPSIG (*wstat
) == SIGFPE
2124 || WSTOPSIG (*wstat
) == SIGBUS
2125 || WSTOPSIG (*wstat
) == SIGSEGV
)
2126 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2127 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2128 /* Final check just to make sure we don't clobber
2129 the siginfo of non-kernel-sent signals. */
2130 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2132 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2133 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2134 (PTRACE_TYPE_ARG3
) 0, &info
);
2137 regcache
= get_thread_regcache (current_thread
, 1);
2138 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
2139 lwp
->stop_pc
= status
.tpoint_addr
;
2141 /* Cancel any fast tracepoint lock this thread was
2143 force_unlock_trace_buffer ();
2146 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2149 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2150 "stopping all threads momentarily.\n");
2152 stop_all_lwps (1, lwp
);
2154 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2155 lwp
->exit_jump_pad_bkpt
= NULL
;
2157 unstop_all_lwps (1, lwp
);
2159 gdb_assert (lwp
->suspended
>= 0);
2165 debug_printf ("Checking whether LWP %ld needs to move out of the "
2167 lwpid_of (current_thread
));
2169 current_thread
= saved_thread
;
2173 /* Enqueue one signal in the "signals to report later when out of the
2177 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2179 struct pending_signals
*p_sig
;
2180 struct thread_info
*thread
= get_lwp_thread (lwp
);
2183 debug_printf ("Deferring signal %d for LWP %ld.\n",
2184 WSTOPSIG (*wstat
), lwpid_of (thread
));
2188 struct pending_signals
*sig
;
2190 for (sig
= lwp
->pending_signals_to_report
;
2193 debug_printf (" Already queued %d\n",
2196 debug_printf (" (no more currently queued signals)\n");
2199 /* Don't enqueue non-RT signals if they are already in the deferred
2200 queue. (SIGSTOP being the easiest signal to see ending up here
2202 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2204 struct pending_signals
*sig
;
2206 for (sig
= lwp
->pending_signals_to_report
;
2210 if (sig
->signal
== WSTOPSIG (*wstat
))
2213 debug_printf ("Not requeuing already queued non-RT signal %d"
2222 p_sig
= XCNEW (struct pending_signals
);
2223 p_sig
->prev
= lwp
->pending_signals_to_report
;
2224 p_sig
->signal
= WSTOPSIG (*wstat
);
2226 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2229 lwp
->pending_signals_to_report
= p_sig
;
2232 /* Dequeue one signal from the "signals to report later when out of
2233 the jump pad" list. */
2236 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2238 struct thread_info
*thread
= get_lwp_thread (lwp
);
2240 if (lwp
->pending_signals_to_report
!= NULL
)
2242 struct pending_signals
**p_sig
;
2244 p_sig
= &lwp
->pending_signals_to_report
;
2245 while ((*p_sig
)->prev
!= NULL
)
2246 p_sig
= &(*p_sig
)->prev
;
2248 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2249 if ((*p_sig
)->info
.si_signo
!= 0)
2250 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2256 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2257 WSTOPSIG (*wstat
), lwpid_of (thread
));
2261 struct pending_signals
*sig
;
2263 for (sig
= lwp
->pending_signals_to_report
;
2266 debug_printf (" Still queued %d\n",
2269 debug_printf (" (no more queued signals)\n");
2278 /* Fetch the possibly triggered data watchpoint info and store it in
2281 On some archs, like x86, that use debug registers to set
2282 watchpoints, it's possible that the way to know which watched
2283 address trapped, is to check the register that is used to select
2284 which address to watch. Problem is, between setting the watchpoint
2285 and reading back which data address trapped, the user may change
2286 the set of watchpoints, and, as a consequence, GDB changes the
2287 debug registers in the inferior. To avoid reading back a stale
2288 stopped-data-address when that happens, we cache in LP the fact
2289 that a watchpoint trapped, and the corresponding data address, as
2290 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2291 registers meanwhile, we have the cached data we can rely on. */
2294 check_stopped_by_watchpoint (struct lwp_info
*child
)
2296 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2298 struct thread_info
*saved_thread
;
2300 saved_thread
= current_thread
;
2301 current_thread
= get_lwp_thread (child
);
2303 if (the_low_target
.stopped_by_watchpoint ())
2305 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2307 if (the_low_target
.stopped_data_address
!= NULL
)
2308 child
->stopped_data_address
2309 = the_low_target
.stopped_data_address ();
2311 child
->stopped_data_address
= 0;
2314 current_thread
= saved_thread
;
2317 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2320 /* Return the ptrace options that we want to try to enable. */
2323 linux_low_ptrace_options (int attached
)
2325 client_state
&cs
= get_client_state ();
2329 options
|= PTRACE_O_EXITKILL
;
2331 if (cs
.report_fork_events
)
2332 options
|= PTRACE_O_TRACEFORK
;
2334 if (cs
.report_vfork_events
)
2335 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2337 if (cs
.report_exec_events
)
2338 options
|= PTRACE_O_TRACEEXEC
;
2340 options
|= PTRACE_O_TRACESYSGOOD
;
2345 /* Do low-level handling of the event, and check if we should go on
2346 and pass it to caller code. Return the affected lwp if we are, or
2349 static struct lwp_info
*
2350 linux_low_filter_event (int lwpid
, int wstat
)
2352 client_state
&cs
= get_client_state ();
2353 struct lwp_info
*child
;
2354 struct thread_info
*thread
;
2355 int have_stop_pc
= 0;
2357 child
= find_lwp_pid (ptid_t (lwpid
));
2359 /* Check for stop events reported by a process we didn't already
2360 know about - anything not already in our LWP list.
2362 If we're expecting to receive stopped processes after
2363 fork, vfork, and clone events, then we'll just add the
2364 new one to our list and go back to waiting for the event
2365 to be reported - the stopped process might be returned
2366 from waitpid before or after the event is.
2368 But note the case of a non-leader thread exec'ing after the
2369 leader having exited, and gone from our lists (because
2370 check_zombie_leaders deleted it). The non-leader thread
2371 changes its tid to the tgid. */
2373 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2374 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2378 /* A multi-thread exec after we had seen the leader exiting. */
2381 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2382 "after exec.\n", lwpid
);
2385 child_ptid
= ptid_t (lwpid
, lwpid
, 0);
2386 child
= add_lwp (child_ptid
);
2388 current_thread
= child
->thread
;
2391 /* If we didn't find a process, one of two things presumably happened:
2392 - A process we started and then detached from has exited. Ignore it.
2393 - A process we are controlling has forked and the new child's stop
2394 was reported to us by the kernel. Save its PID. */
2395 if (child
== NULL
&& WIFSTOPPED (wstat
))
2397 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2400 else if (child
== NULL
)
2403 thread
= get_lwp_thread (child
);
2407 child
->last_status
= wstat
;
2409 /* Check if the thread has exited. */
2410 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2413 debug_printf ("LLFE: %d exited.\n", lwpid
);
2415 if (finish_step_over (child
))
2417 /* Unsuspend all other LWPs, and set them back running again. */
2418 unsuspend_all_lwps (child
);
2421 /* If there is at least one more LWP, then the exit signal was
2422 not the end of the debugged application and should be
2423 ignored, unless GDB wants to hear about thread exits. */
2424 if (cs
.report_thread_events
2425 || last_thread_of_process_p (pid_of (thread
)))
2427 /* Since events are serialized to GDB core, and we can't
2428 report this one right now. Leave the status pending for
2429 the next time we're able to report it. */
2430 mark_lwp_dead (child
, wstat
);
2440 gdb_assert (WIFSTOPPED (wstat
));
2442 if (WIFSTOPPED (wstat
))
2444 struct process_info
*proc
;
2446 /* Architecture-specific setup after inferior is running. */
2447 proc
= find_process_pid (pid_of (thread
));
2448 if (proc
->tdesc
== NULL
)
2452 /* This needs to happen after we have attached to the
2453 inferior and it is stopped for the first time, but
2454 before we access any inferior registers. */
2455 linux_arch_setup_thread (thread
);
2459 /* The process is started, but GDBserver will do
2460 architecture-specific setup after the program stops at
2461 the first instruction. */
2462 child
->status_pending_p
= 1;
2463 child
->status_pending
= wstat
;
2469 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2471 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2472 int options
= linux_low_ptrace_options (proc
->attached
);
2474 linux_enable_event_reporting (lwpid
, options
);
2475 child
->must_set_ptrace_flags
= 0;
2478 /* Always update syscall_state, even if it will be filtered later. */
2479 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2481 child
->syscall_state
2482 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2483 ? TARGET_WAITKIND_SYSCALL_RETURN
2484 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2488 /* Almost all other ptrace-stops are known to be outside of system
2489 calls, with further exceptions in handle_extended_wait. */
2490 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2493 /* Be careful to not overwrite stop_pc until save_stop_reason is
2495 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2496 && linux_is_extended_waitstatus (wstat
))
2498 child
->stop_pc
= get_pc (child
);
2499 if (handle_extended_wait (&child
, wstat
))
2501 /* The event has been handled, so just return without
2507 if (linux_wstatus_maybe_breakpoint (wstat
))
2509 if (save_stop_reason (child
))
2514 child
->stop_pc
= get_pc (child
);
2516 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2517 && child
->stop_expected
)
2520 debug_printf ("Expected stop.\n");
2521 child
->stop_expected
= 0;
2523 if (thread
->last_resume_kind
== resume_stop
)
2525 /* We want to report the stop to the core. Treat the
2526 SIGSTOP as a normal event. */
2528 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2529 target_pid_to_str (ptid_of (thread
)));
2531 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2533 /* Stopping threads. We don't want this SIGSTOP to end up
2536 debug_printf ("LLW: SIGSTOP caught for %s "
2537 "while stopping threads.\n",
2538 target_pid_to_str (ptid_of (thread
)));
2543 /* This is a delayed SIGSTOP. Filter out the event. */
2545 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2546 child
->stepping
? "step" : "continue",
2547 target_pid_to_str (ptid_of (thread
)));
2549 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2554 child
->status_pending_p
= 1;
2555 child
->status_pending
= wstat
;
2559 /* Return true if THREAD is doing hardware single step. */
2562 maybe_hw_step (struct thread_info
*thread
)
2564 if (can_hardware_single_step ())
2568 /* GDBserver must insert single-step breakpoint for software
2570 gdb_assert (has_single_step_breakpoints (thread
));
2575 /* Resume LWPs that are currently stopped without any pending status
2576 to report, but are resumed from the core's perspective. */
2579 resume_stopped_resumed_lwps (thread_info
*thread
)
2581 struct lwp_info
*lp
= get_thread_lwp (thread
);
2585 && !lp
->status_pending_p
2586 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2590 if (thread
->last_resume_kind
== resume_step
)
2591 step
= maybe_hw_step (thread
);
2594 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2595 target_pid_to_str (ptid_of (thread
)),
2596 paddress (lp
->stop_pc
),
2599 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2603 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2604 match FILTER_PTID (leaving others pending). The PTIDs can be:
2605 minus_one_ptid, to specify any child; a pid PTID, specifying all
2606 lwps of a thread group; or a PTID representing a single lwp. Store
2607 the stop status through the status pointer WSTAT. OPTIONS is
2608 passed to the waitpid call. Return 0 if no event was found and
2609 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2610 was found. Return the PID of the stopped child otherwise. */
2613 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2614 int *wstatp
, int options
)
2616 struct thread_info
*event_thread
;
2617 struct lwp_info
*event_child
, *requested_child
;
2618 sigset_t block_mask
, prev_mask
;
2621 /* N.B. event_thread points to the thread_info struct that contains
2622 event_child. Keep them in sync. */
2623 event_thread
= NULL
;
2625 requested_child
= NULL
;
2627 /* Check for a lwp with a pending status. */
2629 if (filter_ptid
== minus_one_ptid
|| filter_ptid
.is_pid ())
2631 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2633 return status_pending_p_callback (thread
, filter_ptid
);
2636 if (event_thread
!= NULL
)
2637 event_child
= get_thread_lwp (event_thread
);
2638 if (debug_threads
&& event_thread
)
2639 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2641 else if (filter_ptid
!= null_ptid
)
2643 requested_child
= find_lwp_pid (filter_ptid
);
2645 if (stopping_threads
== NOT_STOPPING_THREADS
2646 && requested_child
->status_pending_p
2647 && (requested_child
->collecting_fast_tracepoint
2648 != fast_tpoint_collect_result::not_collecting
))
2650 enqueue_one_deferred_signal (requested_child
,
2651 &requested_child
->status_pending
);
2652 requested_child
->status_pending_p
= 0;
2653 requested_child
->status_pending
= 0;
2654 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2657 if (requested_child
->suspended
2658 && requested_child
->status_pending_p
)
2660 internal_error (__FILE__
, __LINE__
,
2661 "requesting an event out of a"
2662 " suspended child?");
2665 if (requested_child
->status_pending_p
)
2667 event_child
= requested_child
;
2668 event_thread
= get_lwp_thread (event_child
);
2672 if (event_child
!= NULL
)
2675 debug_printf ("Got an event from pending child %ld (%04x)\n",
2676 lwpid_of (event_thread
), event_child
->status_pending
);
2677 *wstatp
= event_child
->status_pending
;
2678 event_child
->status_pending_p
= 0;
2679 event_child
->status_pending
= 0;
2680 current_thread
= event_thread
;
2681 return lwpid_of (event_thread
);
2684 /* But if we don't find a pending event, we'll have to wait.
2686 We only enter this loop if no process has a pending wait status.
2687 Thus any action taken in response to a wait status inside this
2688 loop is responding as soon as we detect the status, not after any
2691 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2692 all signals while here. */
2693 sigfillset (&block_mask
);
2694 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2696 /* Always pull all events out of the kernel. We'll randomly select
2697 an event LWP out of all that have events, to prevent
2699 while (event_child
== NULL
)
2703 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2706 - If the thread group leader exits while other threads in the
2707 thread group still exist, waitpid(TGID, ...) hangs. That
2708 waitpid won't return an exit status until the other threads
2709 in the group are reaped.
2711 - When a non-leader thread execs, that thread just vanishes
2712 without reporting an exit (so we'd hang if we waited for it
2713 explicitly in that case). The exec event is reported to
2716 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2719 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2720 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2726 debug_printf ("LLW: waitpid %ld received %s\n",
2727 (long) ret
, status_to_str (*wstatp
));
2730 /* Filter all events. IOW, leave all events pending. We'll
2731 randomly select an event LWP out of all that have events
2733 linux_low_filter_event (ret
, *wstatp
);
2734 /* Retry until nothing comes out of waitpid. A single
2735 SIGCHLD can indicate more than one child stopped. */
2739 /* Now that we've pulled all events out of the kernel, resume
2740 LWPs that don't have an interesting event to report. */
2741 if (stopping_threads
== NOT_STOPPING_THREADS
)
2742 for_each_thread (resume_stopped_resumed_lwps
);
2744 /* ... and find an LWP with a status to report to the core, if
2746 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2748 return status_pending_p_callback (thread
, filter_ptid
);
2751 if (event_thread
!= NULL
)
2753 event_child
= get_thread_lwp (event_thread
);
2754 *wstatp
= event_child
->status_pending
;
2755 event_child
->status_pending_p
= 0;
2756 event_child
->status_pending
= 0;
2760 /* Check for zombie thread group leaders. Those can't be reaped
2761 until all other threads in the thread group are. */
2762 check_zombie_leaders ();
2764 auto not_stopped
= [&] (thread_info
*thread
)
2766 return not_stopped_callback (thread
, wait_ptid
);
2769 /* If there are no resumed children left in the set of LWPs we
2770 want to wait for, bail. We can't just block in
2771 waitpid/sigsuspend, because lwps might have been left stopped
2772 in trace-stop state, and we'd be stuck forever waiting for
2773 their status to change (which would only happen if we resumed
2774 them). Even if WNOHANG is set, this return code is preferred
2775 over 0 (below), as it is more detailed. */
2776 if (find_thread (not_stopped
) == NULL
)
2779 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2780 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2784 /* No interesting event to report to the caller. */
2785 if ((options
& WNOHANG
))
2788 debug_printf ("WNOHANG set, no event found\n");
2790 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2794 /* Block until we get an event reported with SIGCHLD. */
2796 debug_printf ("sigsuspend'ing\n");
2798 sigsuspend (&prev_mask
);
2799 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2803 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2805 current_thread
= event_thread
;
2807 return lwpid_of (event_thread
);
2810 /* Wait for an event from child(ren) PTID. PTIDs can be:
2811 minus_one_ptid, to specify any child; a pid PTID, specifying all
2812 lwps of a thread group; or a PTID representing a single lwp. Store
2813 the stop status through the status pointer WSTAT. OPTIONS is
2814 passed to the waitpid call. Return 0 if no event was found and
2815 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2816 was found. Return the PID of the stopped child otherwise. */
2819 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2821 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2824 /* Select one LWP out of those that have events pending. */
2827 select_event_lwp (struct lwp_info
**orig_lp
)
2829 int random_selector
;
2830 struct thread_info
*event_thread
= NULL
;
2832 /* In all-stop, give preference to the LWP that is being
2833 single-stepped. There will be at most one, and it's the LWP that
2834 the core is most interested in. If we didn't do this, then we'd
2835 have to handle pending step SIGTRAPs somehow in case the core
2836 later continues the previously-stepped thread, otherwise we'd
2837 report the pending SIGTRAP, and the core, not having stepped the
2838 thread, wouldn't understand what the trap was for, and therefore
2839 would report it to the user as a random signal. */
2842 event_thread
= find_thread ([] (thread_info
*thread
)
2844 lwp_info
*lp
= get_thread_lwp (thread
);
2846 return (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2847 && thread
->last_resume_kind
== resume_step
2848 && lp
->status_pending_p
);
2851 if (event_thread
!= NULL
)
2854 debug_printf ("SEL: Select single-step %s\n",
2855 target_pid_to_str (ptid_of (event_thread
)));
2858 if (event_thread
== NULL
)
2860 /* No single-stepping LWP. Select one at random, out of those
2861 which have had events. */
2863 /* First see how many events we have. */
2865 for_each_thread ([&] (thread_info
*thread
)
2867 lwp_info
*lp
= get_thread_lwp (thread
);
2869 /* Count only resumed LWPs that have an event pending. */
2870 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2871 && lp
->status_pending_p
)
2874 gdb_assert (num_events
> 0);
2876 /* Now randomly pick a LWP out of those that have had
2878 random_selector
= (int)
2879 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2881 if (debug_threads
&& num_events
> 1)
2882 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2883 num_events
, random_selector
);
2885 event_thread
= find_thread ([&] (thread_info
*thread
)
2887 lwp_info
*lp
= get_thread_lwp (thread
);
2889 /* Select only resumed LWPs that have an event pending. */
2890 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2891 && lp
->status_pending_p
)
2892 if (random_selector
-- == 0)
2899 if (event_thread
!= NULL
)
2901 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2903 /* Switch the event LWP. */
2904 *orig_lp
= event_lp
;
2908 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2912 unsuspend_all_lwps (struct lwp_info
*except
)
2914 for_each_thread ([&] (thread_info
*thread
)
2916 lwp_info
*lwp
= get_thread_lwp (thread
);
2919 lwp_suspended_decr (lwp
);
2923 static void move_out_of_jump_pad_callback (thread_info
*thread
);
2924 static bool stuck_in_jump_pad_callback (thread_info
*thread
);
2925 static bool lwp_running (thread_info
*thread
);
2926 static ptid_t
linux_wait_1 (ptid_t ptid
,
2927 struct target_waitstatus
*ourstatus
,
2928 int target_options
);
2930 /* Stabilize threads (move out of jump pads).
2932 If a thread is midway collecting a fast tracepoint, we need to
2933 finish the collection and move it out of the jump pad before
2934 reporting the signal.
2936 This avoids recursion while collecting (when a signal arrives
2937 midway, and the signal handler itself collects), which would trash
2938 the trace buffer. In case the user set a breakpoint in a signal
2939 handler, this avoids the backtrace showing the jump pad, etc..
2940 Most importantly, there are certain things we can't do safely if
2941 threads are stopped in a jump pad (or in its callee's). For
2944 - starting a new trace run. A thread still collecting the
2945 previous run, could trash the trace buffer when resumed. The trace
2946 buffer control structures would have been reset but the thread had
2947 no way to tell. The thread could even midway memcpy'ing to the
2948 buffer, which would mean that when resumed, it would clobber the
2949 trace buffer that had been set for a new run.
2951 - we can't rewrite/reuse the jump pads for new tracepoints
2952 safely. Say you do tstart while a thread is stopped midway while
2953 collecting. When the thread is later resumed, it finishes the
2954 collection, and returns to the jump pad, to execute the original
2955 instruction that was under the tracepoint jump at the time the
2956 older run had been started. If the jump pad had been rewritten
2957 since for something else in the new run, the thread would now
2958 execute the wrong / random instructions. */
2961 linux_stabilize_threads (void)
2963 thread_info
*thread_stuck
= find_thread (stuck_in_jump_pad_callback
);
2965 if (thread_stuck
!= NULL
)
2968 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2969 lwpid_of (thread_stuck
));
2973 thread_info
*saved_thread
= current_thread
;
2975 stabilizing_threads
= 1;
2978 for_each_thread (move_out_of_jump_pad_callback
);
2980 /* Loop until all are stopped out of the jump pads. */
2981 while (find_thread (lwp_running
) != NULL
)
2983 struct target_waitstatus ourstatus
;
2984 struct lwp_info
*lwp
;
2987 /* Note that we go through the full wait even loop. While
2988 moving threads out of jump pad, we need to be able to step
2989 over internal breakpoints and such. */
2990 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2992 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2994 lwp
= get_thread_lwp (current_thread
);
2997 lwp_suspended_inc (lwp
);
2999 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
3000 || current_thread
->last_resume_kind
== resume_stop
)
3002 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
3003 enqueue_one_deferred_signal (lwp
, &wstat
);
3008 unsuspend_all_lwps (NULL
);
3010 stabilizing_threads
= 0;
3012 current_thread
= saved_thread
;
3016 thread_stuck
= find_thread (stuck_in_jump_pad_callback
);
3018 if (thread_stuck
!= NULL
)
3019 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
3020 lwpid_of (thread_stuck
));
3024 /* Convenience function that is called when the kernel reports an
3025 event that is not passed out to GDB. */
3028 ignore_event (struct target_waitstatus
*ourstatus
)
3030 /* If we got an event, there may still be others, as a single
3031 SIGCHLD can indicate more than one child stopped. This forces
3032 another target_wait call. */
3035 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3039 /* Convenience function that is called when the kernel reports an exit
3040 event. This decides whether to report the event to GDB as a
3041 process exit event, a thread exit event, or to suppress the
3045 filter_exit_event (struct lwp_info
*event_child
,
3046 struct target_waitstatus
*ourstatus
)
3048 client_state
&cs
= get_client_state ();
3049 struct thread_info
*thread
= get_lwp_thread (event_child
);
3050 ptid_t ptid
= ptid_of (thread
);
3052 if (!last_thread_of_process_p (pid_of (thread
)))
3054 if (cs
.report_thread_events
)
3055 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
3057 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3059 delete_lwp (event_child
);
3064 /* Returns 1 if GDB is interested in any event_child syscalls. */
3067 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
3069 struct thread_info
*thread
= get_lwp_thread (event_child
);
3070 struct process_info
*proc
= get_thread_process (thread
);
3072 return !proc
->syscalls_to_catch
.empty ();
3075 /* Returns 1 if GDB is interested in the event_child syscall.
3076 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3079 gdb_catch_this_syscall_p (struct lwp_info
*event_child
)
3082 struct thread_info
*thread
= get_lwp_thread (event_child
);
3083 struct process_info
*proc
= get_thread_process (thread
);
3085 if (proc
->syscalls_to_catch
.empty ())
3088 if (proc
->syscalls_to_catch
[0] == ANY_SYSCALL
)
3091 get_syscall_trapinfo (event_child
, &sysno
);
3093 for (int iter
: proc
->syscalls_to_catch
)
3100 /* Wait for process, returns status. */
3103 linux_wait_1 (ptid_t ptid
,
3104 struct target_waitstatus
*ourstatus
, int target_options
)
3106 client_state
&cs
= get_client_state ();
3108 struct lwp_info
*event_child
;
3111 int step_over_finished
;
3112 int bp_explains_trap
;
3113 int maybe_internal_trap
;
3122 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
3125 /* Translate generic target options into linux options. */
3127 if (target_options
& TARGET_WNOHANG
)
3130 bp_explains_trap
= 0;
3133 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3135 auto status_pending_p_any
= [&] (thread_info
*thread
)
3137 return status_pending_p_callback (thread
, minus_one_ptid
);
3140 auto not_stopped
= [&] (thread_info
*thread
)
3142 return not_stopped_callback (thread
, minus_one_ptid
);
3145 /* Find a resumed LWP, if any. */
3146 if (find_thread (status_pending_p_any
) != NULL
)
3148 else if (find_thread (not_stopped
) != NULL
)
3153 if (step_over_bkpt
== null_ptid
)
3154 pid
= linux_wait_for_event (ptid
, &w
, options
);
3158 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3159 target_pid_to_str (step_over_bkpt
));
3160 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3163 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3165 gdb_assert (target_options
& TARGET_WNOHANG
);
3169 debug_printf ("linux_wait_1 ret = null_ptid, "
3170 "TARGET_WAITKIND_IGNORE\n");
3174 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3181 debug_printf ("linux_wait_1 ret = null_ptid, "
3182 "TARGET_WAITKIND_NO_RESUMED\n");
3186 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3190 event_child
= get_thread_lwp (current_thread
);
3192 /* linux_wait_for_event only returns an exit status for the last
3193 child of a process. Report it. */
3194 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3198 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3199 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3203 debug_printf ("linux_wait_1 ret = %s, exited with "
3205 target_pid_to_str (ptid_of (current_thread
)),
3212 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3213 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3217 debug_printf ("linux_wait_1 ret = %s, terminated with "
3219 target_pid_to_str (ptid_of (current_thread
)),
3225 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3226 return filter_exit_event (event_child
, ourstatus
);
3228 return ptid_of (current_thread
);
3231 /* If step-over executes a breakpoint instruction, in the case of a
3232 hardware single step it means a gdb/gdbserver breakpoint had been
3233 planted on top of a permanent breakpoint, in the case of a software
3234 single step it may just mean that gdbserver hit the reinsert breakpoint.
3235 The PC has been adjusted by save_stop_reason to point at
3236 the breakpoint address.
3237 So in the case of the hardware single step advance the PC manually
3238 past the breakpoint and in the case of software single step advance only
3239 if it's not the single_step_breakpoint we are hitting.
3240 This avoids that a program would keep trapping a permanent breakpoint
3242 if (step_over_bkpt
!= null_ptid
3243 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3244 && (event_child
->stepping
3245 || !single_step_breakpoint_inserted_here (event_child
->stop_pc
)))
3247 int increment_pc
= 0;
3248 int breakpoint_kind
= 0;
3249 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3252 the_target
->breakpoint_kind_from_current_state (&stop_pc
);
3253 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3257 debug_printf ("step-over for %s executed software breakpoint\n",
3258 target_pid_to_str (ptid_of (current_thread
)));
3261 if (increment_pc
!= 0)
3263 struct regcache
*regcache
3264 = get_thread_regcache (current_thread
, 1);
3266 event_child
->stop_pc
+= increment_pc
;
3267 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3269 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3270 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3274 /* If this event was not handled before, and is not a SIGTRAP, we
3275 report it. SIGILL and SIGSEGV are also treated as traps in case
3276 a breakpoint is inserted at the current PC. If this target does
3277 not support internal breakpoints at all, we also report the
3278 SIGTRAP without further processing; it's of no concern to us. */
3280 = (supports_breakpoints ()
3281 && (WSTOPSIG (w
) == SIGTRAP
3282 || ((WSTOPSIG (w
) == SIGILL
3283 || WSTOPSIG (w
) == SIGSEGV
)
3284 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3286 if (maybe_internal_trap
)
3288 /* Handle anything that requires bookkeeping before deciding to
3289 report the event or continue waiting. */
3291 /* First check if we can explain the SIGTRAP with an internal
3292 breakpoint, or if we should possibly report the event to GDB.
3293 Do this before anything that may remove or insert a
3295 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3297 /* We have a SIGTRAP, possibly a step-over dance has just
3298 finished. If so, tweak the state machine accordingly,
3299 reinsert breakpoints and delete any single-step
3301 step_over_finished
= finish_step_over (event_child
);
3303 /* Now invoke the callbacks of any internal breakpoints there. */
3304 check_breakpoints (event_child
->stop_pc
);
3306 /* Handle tracepoint data collecting. This may overflow the
3307 trace buffer, and cause a tracing stop, removing
3309 trace_event
= handle_tracepoints (event_child
);
3311 if (bp_explains_trap
)
3314 debug_printf ("Hit a gdbserver breakpoint.\n");
3319 /* We have some other signal, possibly a step-over dance was in
3320 progress, and it should be cancelled too. */
3321 step_over_finished
= finish_step_over (event_child
);
3324 /* We have all the data we need. Either report the event to GDB, or
3325 resume threads and keep waiting for more. */
3327 /* If we're collecting a fast tracepoint, finish the collection and
3328 move out of the jump pad before delivering a signal. See
3329 linux_stabilize_threads. */
3332 && WSTOPSIG (w
) != SIGTRAP
3333 && supports_fast_tracepoints ()
3334 && agent_loaded_p ())
3337 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3338 "to defer or adjust it.\n",
3339 WSTOPSIG (w
), lwpid_of (current_thread
));
3341 /* Allow debugging the jump pad itself. */
3342 if (current_thread
->last_resume_kind
!= resume_step
3343 && maybe_move_out_of_jump_pad (event_child
, &w
))
3345 enqueue_one_deferred_signal (event_child
, &w
);
3348 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3349 WSTOPSIG (w
), lwpid_of (current_thread
));
3351 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3355 return ignore_event (ourstatus
);
3359 if (event_child
->collecting_fast_tracepoint
3360 != fast_tpoint_collect_result::not_collecting
)
3363 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3364 "Check if we're already there.\n",
3365 lwpid_of (current_thread
),
3366 (int) event_child
->collecting_fast_tracepoint
);
3370 event_child
->collecting_fast_tracepoint
3371 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3373 if (event_child
->collecting_fast_tracepoint
3374 != fast_tpoint_collect_result::before_insn
)
3376 /* No longer need this breakpoint. */
3377 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3380 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3381 "stopping all threads momentarily.\n");
3383 /* Other running threads could hit this breakpoint.
3384 We don't handle moribund locations like GDB does,
3385 instead we always pause all threads when removing
3386 breakpoints, so that any step-over or
3387 decr_pc_after_break adjustment is always taken
3388 care of while the breakpoint is still
3390 stop_all_lwps (1, event_child
);
3392 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3393 event_child
->exit_jump_pad_bkpt
= NULL
;
3395 unstop_all_lwps (1, event_child
);
3397 gdb_assert (event_child
->suspended
>= 0);
3401 if (event_child
->collecting_fast_tracepoint
3402 == fast_tpoint_collect_result::not_collecting
)
3405 debug_printf ("fast tracepoint finished "
3406 "collecting successfully.\n");
3408 /* We may have a deferred signal to report. */
3409 if (dequeue_one_deferred_signal (event_child
, &w
))
3412 debug_printf ("dequeued one signal.\n");
3417 debug_printf ("no deferred signals.\n");
3419 if (stabilizing_threads
)
3421 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3422 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3426 debug_printf ("linux_wait_1 ret = %s, stopped "
3427 "while stabilizing threads\n",
3428 target_pid_to_str (ptid_of (current_thread
)));
3432 return ptid_of (current_thread
);
3438 /* Check whether GDB would be interested in this event. */
3440 /* Check if GDB is interested in this syscall. */
3442 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3443 && !gdb_catch_this_syscall_p (event_child
))
3447 debug_printf ("Ignored syscall for LWP %ld.\n",
3448 lwpid_of (current_thread
));
3451 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3456 return ignore_event (ourstatus
);
3459 /* If GDB is not interested in this signal, don't stop other
3460 threads, and don't report it to GDB. Just resume the inferior
3461 right away. We do this for threading-related signals as well as
3462 any that GDB specifically requested we ignore. But never ignore
3463 SIGSTOP if we sent it ourselves, and do not ignore signals when
3464 stepping - they may require special handling to skip the signal
3465 handler. Also never ignore signals that could be caused by a
3468 && current_thread
->last_resume_kind
!= resume_step
3470 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3471 (current_process ()->priv
->thread_db
!= NULL
3472 && (WSTOPSIG (w
) == __SIGRTMIN
3473 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3476 (cs
.pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3477 && !(WSTOPSIG (w
) == SIGSTOP
3478 && current_thread
->last_resume_kind
== resume_stop
)
3479 && !linux_wstatus_maybe_breakpoint (w
))))
3481 siginfo_t info
, *info_p
;
3484 debug_printf ("Ignored signal %d for LWP %ld.\n",
3485 WSTOPSIG (w
), lwpid_of (current_thread
));
3487 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3488 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3493 if (step_over_finished
)
3495 /* We cancelled this thread's step-over above. We still
3496 need to unsuspend all other LWPs, and set them back
3497 running again while the signal handler runs. */
3498 unsuspend_all_lwps (event_child
);
3500 /* Enqueue the pending signal info so that proceed_all_lwps
3502 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3504 proceed_all_lwps ();
3508 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3509 WSTOPSIG (w
), info_p
);
3515 return ignore_event (ourstatus
);
3518 /* Note that all addresses are always "out of the step range" when
3519 there's no range to begin with. */
3520 in_step_range
= lwp_in_step_range (event_child
);
3522 /* If GDB wanted this thread to single step, and the thread is out
3523 of the step range, we always want to report the SIGTRAP, and let
3524 GDB handle it. Watchpoints should always be reported. So should
3525 signals we can't explain. A SIGTRAP we can't explain could be a
3526 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3527 do, we're be able to handle GDB breakpoints on top of internal
3528 breakpoints, by handling the internal breakpoint and still
3529 reporting the event to GDB. If we don't, we're out of luck, GDB
3530 won't see the breakpoint hit. If we see a single-step event but
3531 the thread should be continuing, don't pass the trap to gdb.
3532 That indicates that we had previously finished a single-step but
3533 left the single-step pending -- see
3534 complete_ongoing_step_over. */
3535 report_to_gdb
= (!maybe_internal_trap
3536 || (current_thread
->last_resume_kind
== resume_step
3538 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3540 && !bp_explains_trap
3542 && !step_over_finished
3543 && !(current_thread
->last_resume_kind
== resume_continue
3544 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3545 || (gdb_breakpoint_here (event_child
->stop_pc
)
3546 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3547 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3548 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3550 run_breakpoint_commands (event_child
->stop_pc
);
3552 /* We found no reason GDB would want us to stop. We either hit one
3553 of our own breakpoints, or finished an internal step GDB
3554 shouldn't know about. */
3559 if (bp_explains_trap
)
3560 debug_printf ("Hit a gdbserver breakpoint.\n");
3561 if (step_over_finished
)
3562 debug_printf ("Step-over finished.\n");
3564 debug_printf ("Tracepoint event.\n");
3565 if (lwp_in_step_range (event_child
))
3566 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3567 paddress (event_child
->stop_pc
),
3568 paddress (event_child
->step_range_start
),
3569 paddress (event_child
->step_range_end
));
3572 /* We're not reporting this breakpoint to GDB, so apply the
3573 decr_pc_after_break adjustment to the inferior's regcache
3576 if (the_low_target
.set_pc
!= NULL
)
3578 struct regcache
*regcache
3579 = get_thread_regcache (current_thread
, 1);
3580 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3583 if (step_over_finished
)
3585 /* If we have finished stepping over a breakpoint, we've
3586 stopped and suspended all LWPs momentarily except the
3587 stepping one. This is where we resume them all again.
3588 We're going to keep waiting, so use proceed, which
3589 handles stepping over the next breakpoint. */
3590 unsuspend_all_lwps (event_child
);
3594 /* Remove the single-step breakpoints if any. Note that
3595 there isn't single-step breakpoint if we finished stepping
3597 if (can_software_single_step ()
3598 && has_single_step_breakpoints (current_thread
))
3600 stop_all_lwps (0, event_child
);
3601 delete_single_step_breakpoints (current_thread
);
3602 unstop_all_lwps (0, event_child
);
3607 debug_printf ("proceeding all threads.\n");
3608 proceed_all_lwps ();
3613 return ignore_event (ourstatus
);
3618 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3621 = target_waitstatus_to_string (&event_child
->waitstatus
);
3623 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3624 lwpid_of (get_lwp_thread (event_child
)), str
.c_str ());
3626 if (current_thread
->last_resume_kind
== resume_step
)
3628 if (event_child
->step_range_start
== event_child
->step_range_end
)
3629 debug_printf ("GDB wanted to single-step, reporting event.\n");
3630 else if (!lwp_in_step_range (event_child
))
3631 debug_printf ("Out of step range, reporting event.\n");
3633 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3634 debug_printf ("Stopped by watchpoint.\n");
3635 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3636 debug_printf ("Stopped by GDB breakpoint.\n");
3638 debug_printf ("Hit a non-gdbserver trap event.\n");
3641 /* Alright, we're going to report a stop. */
3643 /* Remove single-step breakpoints. */
3644 if (can_software_single_step ())
3646 /* Remove single-step breakpoints or not. It it is true, stop all
3647 lwps, so that other threads won't hit the breakpoint in the
3649 int remove_single_step_breakpoints_p
= 0;
3653 remove_single_step_breakpoints_p
3654 = has_single_step_breakpoints (current_thread
);
3658 /* In all-stop, a stop reply cancels all previous resume
3659 requests. Delete all single-step breakpoints. */
3661 find_thread ([&] (thread_info
*thread
) {
3662 if (has_single_step_breakpoints (thread
))
3664 remove_single_step_breakpoints_p
= 1;
3672 if (remove_single_step_breakpoints_p
)
3674 /* If we remove single-step breakpoints from memory, stop all lwps,
3675 so that other threads won't hit the breakpoint in the staled
3677 stop_all_lwps (0, event_child
);
3681 gdb_assert (has_single_step_breakpoints (current_thread
));
3682 delete_single_step_breakpoints (current_thread
);
3686 for_each_thread ([] (thread_info
*thread
){
3687 if (has_single_step_breakpoints (thread
))
3688 delete_single_step_breakpoints (thread
);
3692 unstop_all_lwps (0, event_child
);
3696 if (!stabilizing_threads
)
3698 /* In all-stop, stop all threads. */
3700 stop_all_lwps (0, NULL
);
3702 if (step_over_finished
)
3706 /* If we were doing a step-over, all other threads but
3707 the stepping one had been paused in start_step_over,
3708 with their suspend counts incremented. We don't want
3709 to do a full unstop/unpause, because we're in
3710 all-stop mode (so we want threads stopped), but we
3711 still need to unsuspend the other threads, to
3712 decrement their `suspended' count back. */
3713 unsuspend_all_lwps (event_child
);
3717 /* If we just finished a step-over, then all threads had
3718 been momentarily paused. In all-stop, that's fine,
3719 we want threads stopped by now anyway. In non-stop,
3720 we need to re-resume threads that GDB wanted to be
3722 unstop_all_lwps (1, event_child
);
3726 /* If we're not waiting for a specific LWP, choose an event LWP
3727 from among those that have had events. Giving equal priority
3728 to all LWPs that have had events helps prevent
3730 if (ptid
== minus_one_ptid
)
3732 event_child
->status_pending_p
= 1;
3733 event_child
->status_pending
= w
;
3735 select_event_lwp (&event_child
);
3737 /* current_thread and event_child must stay in sync. */
3738 current_thread
= get_lwp_thread (event_child
);
3740 event_child
->status_pending_p
= 0;
3741 w
= event_child
->status_pending
;
3745 /* Stabilize threads (move out of jump pads). */
3747 stabilize_threads ();
3751 /* If we just finished a step-over, then all threads had been
3752 momentarily paused. In all-stop, that's fine, we want
3753 threads stopped by now anyway. In non-stop, we need to
3754 re-resume threads that GDB wanted to be running. */
3755 if (step_over_finished
)
3756 unstop_all_lwps (1, event_child
);
3759 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3761 /* If the reported event is an exit, fork, vfork or exec, let
3764 /* Break the unreported fork relationship chain. */
3765 if (event_child
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
3766 || event_child
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
)
3768 event_child
->fork_relative
->fork_relative
= NULL
;
3769 event_child
->fork_relative
= NULL
;
3772 *ourstatus
= event_child
->waitstatus
;
3773 /* Clear the event lwp's waitstatus since we handled it already. */
3774 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3777 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3779 /* Now that we've selected our final event LWP, un-adjust its PC if
3780 it was a software breakpoint, and the client doesn't know we can
3781 adjust the breakpoint ourselves. */
3782 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3783 && !cs
.swbreak_feature
)
3785 int decr_pc
= the_low_target
.decr_pc_after_break
;
3789 struct regcache
*regcache
3790 = get_thread_regcache (current_thread
, 1);
3791 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3795 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3797 get_syscall_trapinfo (event_child
,
3798 &ourstatus
->value
.syscall_number
);
3799 ourstatus
->kind
= event_child
->syscall_state
;
3801 else if (current_thread
->last_resume_kind
== resume_stop
3802 && WSTOPSIG (w
) == SIGSTOP
)
3804 /* A thread that has been requested to stop by GDB with vCont;t,
3805 and it stopped cleanly, so report as SIG0. The use of
3806 SIGSTOP is an implementation detail. */
3807 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3809 else if (current_thread
->last_resume_kind
== resume_stop
3810 && WSTOPSIG (w
) != SIGSTOP
)
3812 /* A thread that has been requested to stop by GDB with vCont;t,
3813 but, it stopped for other reasons. */
3814 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3816 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3818 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3821 gdb_assert (step_over_bkpt
== null_ptid
);
3825 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3826 target_pid_to_str (ptid_of (current_thread
)),
3827 ourstatus
->kind
, ourstatus
->value
.sig
);
3831 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3832 return filter_exit_event (event_child
, ourstatus
);
3834 return ptid_of (current_thread
);
3837 /* Get rid of any pending event in the pipe. */
3839 async_file_flush (void)
3845 ret
= read (linux_event_pipe
[0], &buf
, 1);
3846 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3849 /* Put something in the pipe, so the event loop wakes up. */
3851 async_file_mark (void)
3855 async_file_flush ();
3858 ret
= write (linux_event_pipe
[1], "+", 1);
3859 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3861 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3862 be awakened anyway. */
3866 linux_wait (ptid_t ptid
,
3867 struct target_waitstatus
*ourstatus
, int target_options
)
3871 /* Flush the async file first. */
3872 if (target_is_async_p ())
3873 async_file_flush ();
3877 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3879 while ((target_options
& TARGET_WNOHANG
) == 0
3880 && event_ptid
== null_ptid
3881 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3883 /* If at least one stop was reported, there may be more. A single
3884 SIGCHLD can signal more than one child stop. */
3885 if (target_is_async_p ()
3886 && (target_options
& TARGET_WNOHANG
) != 0
3887 && event_ptid
!= null_ptid
)
3893 /* Send a signal to an LWP. */
3896 kill_lwp (unsigned long lwpid
, int signo
)
3901 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3902 if (errno
== ENOSYS
)
3904 /* If tkill fails, then we are not using nptl threads, a
3905 configuration we no longer support. */
3906 perror_with_name (("tkill"));
3912 linux_stop_lwp (struct lwp_info
*lwp
)
3918 send_sigstop (struct lwp_info
*lwp
)
3922 pid
= lwpid_of (get_lwp_thread (lwp
));
3924 /* If we already have a pending stop signal for this process, don't
3926 if (lwp
->stop_expected
)
3929 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3935 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3937 lwp
->stop_expected
= 1;
3938 kill_lwp (pid
, SIGSTOP
);
3942 send_sigstop (thread_info
*thread
, lwp_info
*except
)
3944 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3946 /* Ignore EXCEPT. */
3956 /* Increment the suspend count of an LWP, and stop it, if not stopped
3959 suspend_and_send_sigstop (thread_info
*thread
, lwp_info
*except
)
3961 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3963 /* Ignore EXCEPT. */
3967 lwp_suspended_inc (lwp
);
3969 send_sigstop (thread
, except
);
3973 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3975 /* Store the exit status for later. */
3976 lwp
->status_pending_p
= 1;
3977 lwp
->status_pending
= wstat
;
3979 /* Store in waitstatus as well, as there's nothing else to process
3981 if (WIFEXITED (wstat
))
3983 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3984 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3986 else if (WIFSIGNALED (wstat
))
3988 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3989 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3992 /* Prevent trying to stop it. */
3995 /* No further stops are expected from a dead lwp. */
3996 lwp
->stop_expected
= 0;
3999 /* Return true if LWP has exited already, and has a pending exit event
4000 to report to GDB. */
4003 lwp_is_marked_dead (struct lwp_info
*lwp
)
4005 return (lwp
->status_pending_p
4006 && (WIFEXITED (lwp
->status_pending
)
4007 || WIFSIGNALED (lwp
->status_pending
)));
4010 /* Wait for all children to stop for the SIGSTOPs we just queued. */
4013 wait_for_sigstop (void)
4015 struct thread_info
*saved_thread
;
4020 saved_thread
= current_thread
;
4021 if (saved_thread
!= NULL
)
4022 saved_tid
= saved_thread
->id
;
4024 saved_tid
= null_ptid
; /* avoid bogus unused warning */
4027 debug_printf ("wait_for_sigstop: pulling events\n");
4029 /* Passing NULL_PTID as filter indicates we want all events to be
4030 left pending. Eventually this returns when there are no
4031 unwaited-for children left. */
4032 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4034 gdb_assert (ret
== -1);
4036 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
4037 current_thread
= saved_thread
;
4041 debug_printf ("Previously current thread died.\n");
4043 /* We can't change the current inferior behind GDB's back,
4044 otherwise, a subsequent command may apply to the wrong
4046 current_thread
= NULL
;
4050 /* Returns true if THREAD is stopped in a jump pad, and we can't
4051 move it out, because we need to report the stop event to GDB. For
4052 example, if the user puts a breakpoint in the jump pad, it's
4053 because she wants to debug it. */
4056 stuck_in_jump_pad_callback (thread_info
*thread
)
4058 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4060 if (lwp
->suspended
!= 0)
4062 internal_error (__FILE__
, __LINE__
,
4063 "LWP %ld is suspended, suspended=%d\n",
4064 lwpid_of (thread
), lwp
->suspended
);
4066 gdb_assert (lwp
->stopped
);
4068 /* Allow debugging the jump pad, gdb_collect, etc.. */
4069 return (supports_fast_tracepoints ()
4070 && agent_loaded_p ()
4071 && (gdb_breakpoint_here (lwp
->stop_pc
)
4072 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
4073 || thread
->last_resume_kind
== resume_step
)
4074 && (linux_fast_tracepoint_collecting (lwp
, NULL
)
4075 != fast_tpoint_collect_result::not_collecting
));
4079 move_out_of_jump_pad_callback (thread_info
*thread
)
4081 struct thread_info
*saved_thread
;
4082 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4085 if (lwp
->suspended
!= 0)
4087 internal_error (__FILE__
, __LINE__
,
4088 "LWP %ld is suspended, suspended=%d\n",
4089 lwpid_of (thread
), lwp
->suspended
);
4091 gdb_assert (lwp
->stopped
);
4093 /* For gdb_breakpoint_here. */
4094 saved_thread
= current_thread
;
4095 current_thread
= thread
;
4097 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
4099 /* Allow debugging the jump pad, gdb_collect, etc. */
4100 if (!gdb_breakpoint_here (lwp
->stop_pc
)
4101 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
4102 && thread
->last_resume_kind
!= resume_step
4103 && maybe_move_out_of_jump_pad (lwp
, wstat
))
4106 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
4111 lwp
->status_pending_p
= 0;
4112 enqueue_one_deferred_signal (lwp
, wstat
);
4115 debug_printf ("Signal %d for LWP %ld deferred "
4117 WSTOPSIG (*wstat
), lwpid_of (thread
));
4120 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
4123 lwp_suspended_inc (lwp
);
4125 current_thread
= saved_thread
;
4129 lwp_running (thread_info
*thread
)
4131 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4133 if (lwp_is_marked_dead (lwp
))
4136 return !lwp
->stopped
;
4139 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4140 If SUSPEND, then also increase the suspend count of every LWP,
4144 stop_all_lwps (int suspend
, struct lwp_info
*except
)
4146 /* Should not be called recursively. */
4147 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
4152 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4153 suspend
? "stop-and-suspend" : "stop",
4155 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
4159 stopping_threads
= (suspend
4160 ? STOPPING_AND_SUSPENDING_THREADS
4161 : STOPPING_THREADS
);
4164 for_each_thread ([&] (thread_info
*thread
)
4166 suspend_and_send_sigstop (thread
, except
);
4169 for_each_thread ([&] (thread_info
*thread
)
4171 send_sigstop (thread
, except
);
4174 wait_for_sigstop ();
4175 stopping_threads
= NOT_STOPPING_THREADS
;
4179 debug_printf ("stop_all_lwps done, setting stopping_threads "
4180 "back to !stopping\n");
4185 /* Enqueue one signal in the chain of signals which need to be
4186 delivered to this process on next resume. */
4189 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4191 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4193 p_sig
->prev
= lwp
->pending_signals
;
4194 p_sig
->signal
= signal
;
4196 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4198 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4199 lwp
->pending_signals
= p_sig
;
4202 /* Install breakpoints for software single stepping. */
4205 install_software_single_step_breakpoints (struct lwp_info
*lwp
)
4207 struct thread_info
*thread
= get_lwp_thread (lwp
);
4208 struct regcache
*regcache
= get_thread_regcache (thread
, 1);
4210 scoped_restore save_current_thread
= make_scoped_restore (¤t_thread
);
4212 current_thread
= thread
;
4213 std::vector
<CORE_ADDR
> next_pcs
= the_low_target
.get_next_pcs (regcache
);
4215 for (CORE_ADDR pc
: next_pcs
)
4216 set_single_step_breakpoint (pc
, current_ptid
);
4219 /* Single step via hardware or software single step.
4220 Return 1 if hardware single stepping, 0 if software single stepping
4221 or can't single step. */
4224 single_step (struct lwp_info
* lwp
)
4228 if (can_hardware_single_step ())
4232 else if (can_software_single_step ())
4234 install_software_single_step_breakpoints (lwp
);
4240 debug_printf ("stepping is not implemented on this target");
4246 /* The signal can be delivered to the inferior if we are not trying to
4247 finish a fast tracepoint collect. Since signal can be delivered in
4248 the step-over, the program may go to signal handler and trap again
4249 after return from the signal handler. We can live with the spurious
4253 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
4255 return (lwp
->collecting_fast_tracepoint
4256 == fast_tpoint_collect_result::not_collecting
);
4259 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4260 SIGNAL is nonzero, give it that signal. */
4263 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
4264 int step
, int signal
, siginfo_t
*info
)
4266 struct thread_info
*thread
= get_lwp_thread (lwp
);
4267 struct thread_info
*saved_thread
;
4269 struct process_info
*proc
= get_thread_process (thread
);
4271 /* Note that target description may not be initialised
4272 (proc->tdesc == NULL) at this point because the program hasn't
4273 stopped at the first instruction yet. It means GDBserver skips
4274 the extra traps from the wrapper program (see option --wrapper).
4275 Code in this function that requires register access should be
4276 guarded by proc->tdesc == NULL or something else. */
4278 if (lwp
->stopped
== 0)
4281 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4283 fast_tpoint_collect_result fast_tp_collecting
4284 = lwp
->collecting_fast_tracepoint
;
4286 gdb_assert (!stabilizing_threads
4287 || (fast_tp_collecting
4288 != fast_tpoint_collect_result::not_collecting
));
4290 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4291 user used the "jump" command, or "set $pc = foo"). */
4292 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4294 /* Collecting 'while-stepping' actions doesn't make sense
4296 release_while_stepping_state_list (thread
);
4299 /* If we have pending signals or status, and a new signal, enqueue the
4300 signal. Also enqueue the signal if it can't be delivered to the
4301 inferior right now. */
4303 && (lwp
->status_pending_p
4304 || lwp
->pending_signals
!= NULL
4305 || !lwp_signal_can_be_delivered (lwp
)))
4307 enqueue_pending_signal (lwp
, signal
, info
);
4309 /* Postpone any pending signal. It was enqueued above. */
4313 if (lwp
->status_pending_p
)
4316 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4317 " has pending status\n",
4318 lwpid_of (thread
), step
? "step" : "continue",
4319 lwp
->stop_expected
? "expected" : "not expected");
4323 saved_thread
= current_thread
;
4324 current_thread
= thread
;
4326 /* This bit needs some thinking about. If we get a signal that
4327 we must report while a single-step reinsert is still pending,
4328 we often end up resuming the thread. It might be better to
4329 (ew) allow a stack of pending events; then we could be sure that
4330 the reinsert happened right away and not lose any signals.
4332 Making this stack would also shrink the window in which breakpoints are
4333 uninserted (see comment in linux_wait_for_lwp) but not enough for
4334 complete correctness, so it won't solve that problem. It may be
4335 worthwhile just to solve this one, however. */
4336 if (lwp
->bp_reinsert
!= 0)
4339 debug_printf (" pending reinsert at 0x%s\n",
4340 paddress (lwp
->bp_reinsert
));
4342 if (can_hardware_single_step ())
4344 if (fast_tp_collecting
== fast_tpoint_collect_result::not_collecting
)
4347 warning ("BAD - reinserting but not stepping.");
4349 warning ("BAD - reinserting and suspended(%d).",
4354 step
= maybe_hw_step (thread
);
4357 if (fast_tp_collecting
== fast_tpoint_collect_result::before_insn
)
4360 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4361 " (exit-jump-pad-bkpt)\n",
4364 else if (fast_tp_collecting
== fast_tpoint_collect_result::at_insn
)
4367 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4368 " single-stepping\n",
4371 if (can_hardware_single_step ())
4375 internal_error (__FILE__
, __LINE__
,
4376 "moving out of jump pad single-stepping"
4377 " not implemented on this target");
4381 /* If we have while-stepping actions in this thread set it stepping.
4382 If we have a signal to deliver, it may or may not be set to
4383 SIG_IGN, we don't know. Assume so, and allow collecting
4384 while-stepping into a signal handler. A possible smart thing to
4385 do would be to set an internal breakpoint at the signal return
4386 address, continue, and carry on catching this while-stepping
4387 action only when that breakpoint is hit. A future
4389 if (thread
->while_stepping
!= NULL
)
4392 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4395 step
= single_step (lwp
);
4398 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4400 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4402 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4406 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4407 (long) lwp
->stop_pc
);
4411 /* If we have pending signals, consume one if it can be delivered to
4413 if (lwp
->pending_signals
!= NULL
&& lwp_signal_can_be_delivered (lwp
))
4415 struct pending_signals
**p_sig
;
4417 p_sig
= &lwp
->pending_signals
;
4418 while ((*p_sig
)->prev
!= NULL
)
4419 p_sig
= &(*p_sig
)->prev
;
4421 signal
= (*p_sig
)->signal
;
4422 if ((*p_sig
)->info
.si_signo
!= 0)
4423 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4431 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4432 lwpid_of (thread
), step
? "step" : "continue", signal
,
4433 lwp
->stop_expected
? "expected" : "not expected");
4435 if (the_low_target
.prepare_to_resume
!= NULL
)
4436 the_low_target
.prepare_to_resume (lwp
);
4438 regcache_invalidate_thread (thread
);
4440 lwp
->stepping
= step
;
4442 ptrace_request
= PTRACE_SINGLESTEP
;
4443 else if (gdb_catching_syscalls_p (lwp
))
4444 ptrace_request
= PTRACE_SYSCALL
;
4446 ptrace_request
= PTRACE_CONT
;
4447 ptrace (ptrace_request
,
4449 (PTRACE_TYPE_ARG3
) 0,
4450 /* Coerce to a uintptr_t first to avoid potential gcc warning
4451 of coercing an 8 byte integer to a 4 byte pointer. */
4452 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4454 current_thread
= saved_thread
;
4456 perror_with_name ("resuming thread");
4458 /* Successfully resumed. Clear state that no longer makes sense,
4459 and mark the LWP as running. Must not do this before resuming
4460 otherwise if that fails other code will be confused. E.g., we'd
4461 later try to stop the LWP and hang forever waiting for a stop
4462 status. Note that we must not throw after this is cleared,
4463 otherwise handle_zombie_lwp_error would get confused. */
4465 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4468 /* Called when we try to resume a stopped LWP and that errors out. If
4469 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4470 or about to become), discard the error, clear any pending status
4471 the LWP may have, and return true (we'll collect the exit status
4472 soon enough). Otherwise, return false. */
4475 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4477 struct thread_info
*thread
= get_lwp_thread (lp
);
4479 /* If we get an error after resuming the LWP successfully, we'd
4480 confuse !T state for the LWP being gone. */
4481 gdb_assert (lp
->stopped
);
4483 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4484 because even if ptrace failed with ESRCH, the tracee may be "not
4485 yet fully dead", but already refusing ptrace requests. In that
4486 case the tracee has 'R (Running)' state for a little bit
4487 (observed in Linux 3.18). See also the note on ESRCH in the
4488 ptrace(2) man page. Instead, check whether the LWP has any state
4489 other than ptrace-stopped. */
4491 /* Don't assume anything if /proc/PID/status can't be read. */
4492 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4494 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4495 lp
->status_pending_p
= 0;
4501 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4502 disappears while we try to resume it. */
4505 linux_resume_one_lwp (struct lwp_info
*lwp
,
4506 int step
, int signal
, siginfo_t
*info
)
4510 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4512 CATCH (ex
, RETURN_MASK_ERROR
)
4514 if (!check_ptrace_stopped_lwp_gone (lwp
))
4515 throw_exception (ex
);
4520 /* This function is called once per thread via for_each_thread.
4521 We look up which resume request applies to THREAD and mark it with a
4522 pointer to the appropriate resume request.
4524 This algorithm is O(threads * resume elements), but resume elements
4525 is small (and will remain small at least until GDB supports thread
4529 linux_set_resume_request (thread_info
*thread
, thread_resume
*resume
, size_t n
)
4531 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4533 for (int ndx
= 0; ndx
< n
; ndx
++)
4535 ptid_t ptid
= resume
[ndx
].thread
;
4536 if (ptid
== minus_one_ptid
4537 || ptid
== thread
->id
4538 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4540 || (ptid
.pid () == pid_of (thread
)
4542 || ptid
.lwp () == -1)))
4544 if (resume
[ndx
].kind
== resume_stop
4545 && thread
->last_resume_kind
== resume_stop
)
4548 debug_printf ("already %s LWP %ld at GDB's request\n",
4549 (thread
->last_status
.kind
4550 == TARGET_WAITKIND_STOPPED
)
4558 /* Ignore (wildcard) resume requests for already-resumed
4560 if (resume
[ndx
].kind
!= resume_stop
4561 && thread
->last_resume_kind
!= resume_stop
)
4564 debug_printf ("already %s LWP %ld at GDB's request\n",
4565 (thread
->last_resume_kind
4573 /* Don't let wildcard resumes resume fork children that GDB
4574 does not yet know are new fork children. */
4575 if (lwp
->fork_relative
!= NULL
)
4577 struct lwp_info
*rel
= lwp
->fork_relative
;
4579 if (rel
->status_pending_p
4580 && (rel
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
4581 || rel
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
))
4584 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4590 /* If the thread has a pending event that has already been
4591 reported to GDBserver core, but GDB has not pulled the
4592 event out of the vStopped queue yet, likewise, ignore the
4593 (wildcard) resume request. */
4594 if (in_queued_stop_replies (thread
->id
))
4597 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4602 lwp
->resume
= &resume
[ndx
];
4603 thread
->last_resume_kind
= lwp
->resume
->kind
;
4605 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4606 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4608 /* If we had a deferred signal to report, dequeue one now.
4609 This can happen if LWP gets more than one signal while
4610 trying to get out of a jump pad. */
4612 && !lwp
->status_pending_p
4613 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4615 lwp
->status_pending_p
= 1;
4618 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4619 "leaving status pending.\n",
4620 WSTOPSIG (lwp
->status_pending
),
4628 /* No resume action for this thread. */
4632 /* find_thread callback for linux_resume. Return true if this lwp has an
4633 interesting status pending. */
4636 resume_status_pending_p (thread_info
*thread
)
4638 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4640 /* LWPs which will not be resumed are not interesting, because
4641 we might not wait for them next time through linux_wait. */
4642 if (lwp
->resume
== NULL
)
4645 return thread_still_has_status_pending_p (thread
);
4648 /* Return 1 if this lwp that GDB wants running is stopped at an
4649 internal breakpoint that we need to step over. It assumes that any
4650 required STOP_PC adjustment has already been propagated to the
4651 inferior's regcache. */
4654 need_step_over_p (thread_info
*thread
)
4656 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4657 struct thread_info
*saved_thread
;
4659 struct process_info
*proc
= get_thread_process (thread
);
4661 /* GDBserver is skipping the extra traps from the wrapper program,
4662 don't have to do step over. */
4663 if (proc
->tdesc
== NULL
)
4666 /* LWPs which will not be resumed are not interesting, because we
4667 might not wait for them next time through linux_wait. */
4672 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4677 if (thread
->last_resume_kind
== resume_stop
)
4680 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4686 gdb_assert (lwp
->suspended
>= 0);
4691 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4696 if (lwp
->status_pending_p
)
4699 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4705 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4709 /* If the PC has changed since we stopped, then don't do anything,
4710 and let the breakpoint/tracepoint be hit. This happens if, for
4711 instance, GDB handled the decr_pc_after_break subtraction itself,
4712 GDB is OOL stepping this thread, or the user has issued a "jump"
4713 command, or poked thread's registers herself. */
4714 if (pc
!= lwp
->stop_pc
)
4717 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4718 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4720 paddress (lwp
->stop_pc
), paddress (pc
));
4724 /* On software single step target, resume the inferior with signal
4725 rather than stepping over. */
4726 if (can_software_single_step ()
4727 && lwp
->pending_signals
!= NULL
4728 && lwp_signal_can_be_delivered (lwp
))
4731 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4738 saved_thread
= current_thread
;
4739 current_thread
= thread
;
4741 /* We can only step over breakpoints we know about. */
4742 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4744 /* Don't step over a breakpoint that GDB expects to hit
4745 though. If the condition is being evaluated on the target's side
4746 and it evaluate to false, step over this breakpoint as well. */
4747 if (gdb_breakpoint_here (pc
)
4748 && gdb_condition_true_at_breakpoint (pc
)
4749 && gdb_no_commands_at_breakpoint (pc
))
4752 debug_printf ("Need step over [LWP %ld]? yes, but found"
4753 " GDB breakpoint at 0x%s; skipping step over\n",
4754 lwpid_of (thread
), paddress (pc
));
4756 current_thread
= saved_thread
;
4762 debug_printf ("Need step over [LWP %ld]? yes, "
4763 "found breakpoint at 0x%s\n",
4764 lwpid_of (thread
), paddress (pc
));
4766 /* We've found an lwp that needs stepping over --- return 1 so
4767 that find_thread stops looking. */
4768 current_thread
= saved_thread
;
4774 current_thread
= saved_thread
;
4777 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4779 lwpid_of (thread
), paddress (pc
));
4784 /* Start a step-over operation on LWP. When LWP stopped at a
4785 breakpoint, to make progress, we need to remove the breakpoint out
4786 of the way. If we let other threads run while we do that, they may
4787 pass by the breakpoint location and miss hitting it. To avoid
4788 that, a step-over momentarily stops all threads while LWP is
4789 single-stepped by either hardware or software while the breakpoint
4790 is temporarily uninserted from the inferior. When the single-step
4791 finishes, we reinsert the breakpoint, and let all threads that are
4792 supposed to be running, run again. */
4795 start_step_over (struct lwp_info
*lwp
)
4797 struct thread_info
*thread
= get_lwp_thread (lwp
);
4798 struct thread_info
*saved_thread
;
4803 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4806 stop_all_lwps (1, lwp
);
4808 if (lwp
->suspended
!= 0)
4810 internal_error (__FILE__
, __LINE__
,
4811 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4816 debug_printf ("Done stopping all threads for step-over.\n");
4818 /* Note, we should always reach here with an already adjusted PC,
4819 either by GDB (if we're resuming due to GDB's request), or by our
4820 caller, if we just finished handling an internal breakpoint GDB
4821 shouldn't care about. */
4824 saved_thread
= current_thread
;
4825 current_thread
= thread
;
4827 lwp
->bp_reinsert
= pc
;
4828 uninsert_breakpoints_at (pc
);
4829 uninsert_fast_tracepoint_jumps_at (pc
);
4831 step
= single_step (lwp
);
4833 current_thread
= saved_thread
;
4835 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4837 /* Require next event from this LWP. */
4838 step_over_bkpt
= thread
->id
;
4842 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4843 start_step_over, if still there, and delete any single-step
4844 breakpoints we've set, on non hardware single-step targets. */
4847 finish_step_over (struct lwp_info
*lwp
)
4849 if (lwp
->bp_reinsert
!= 0)
4851 struct thread_info
*saved_thread
= current_thread
;
4854 debug_printf ("Finished step over.\n");
4856 current_thread
= get_lwp_thread (lwp
);
4858 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4859 may be no breakpoint to reinsert there by now. */
4860 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4861 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4863 lwp
->bp_reinsert
= 0;
4865 /* Delete any single-step breakpoints. No longer needed. We
4866 don't have to worry about other threads hitting this trap,
4867 and later not being able to explain it, because we were
4868 stepping over a breakpoint, and we hold all threads but
4869 LWP stopped while doing that. */
4870 if (!can_hardware_single_step ())
4872 gdb_assert (has_single_step_breakpoints (current_thread
));
4873 delete_single_step_breakpoints (current_thread
);
4876 step_over_bkpt
= null_ptid
;
4877 current_thread
= saved_thread
;
4884 /* If there's a step over in progress, wait until all threads stop
4885 (that is, until the stepping thread finishes its step), and
4886 unsuspend all lwps. The stepping thread ends with its status
4887 pending, which is processed later when we get back to processing
4891 complete_ongoing_step_over (void)
4893 if (step_over_bkpt
!= null_ptid
)
4895 struct lwp_info
*lwp
;
4900 debug_printf ("detach: step over in progress, finish it first\n");
4902 /* Passing NULL_PTID as filter indicates we want all events to
4903 be left pending. Eventually this returns when there are no
4904 unwaited-for children left. */
4905 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4907 gdb_assert (ret
== -1);
4909 lwp
= find_lwp_pid (step_over_bkpt
);
4911 finish_step_over (lwp
);
4912 step_over_bkpt
= null_ptid
;
4913 unsuspend_all_lwps (lwp
);
4917 /* This function is called once per thread. We check the thread's resume
4918 request, which will tell us whether to resume, step, or leave the thread
4919 stopped; and what signal, if any, it should be sent.
4921 For threads which we aren't explicitly told otherwise, we preserve
4922 the stepping flag; this is used for stepping over gdbserver-placed
4925 If pending_flags was set in any thread, we queue any needed
4926 signals, since we won't actually resume. We already have a pending
4927 event to report, so we don't need to preserve any step requests;
4928 they should be re-issued if necessary. */
4931 linux_resume_one_thread (thread_info
*thread
, bool leave_all_stopped
)
4933 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4936 if (lwp
->resume
== NULL
)
4939 if (lwp
->resume
->kind
== resume_stop
)
4942 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4947 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4949 /* Stop the thread, and wait for the event asynchronously,
4950 through the event loop. */
4956 debug_printf ("already stopped LWP %ld\n",
4959 /* The LWP may have been stopped in an internal event that
4960 was not meant to be notified back to GDB (e.g., gdbserver
4961 breakpoint), so we should be reporting a stop event in
4964 /* If the thread already has a pending SIGSTOP, this is a
4965 no-op. Otherwise, something later will presumably resume
4966 the thread and this will cause it to cancel any pending
4967 operation, due to last_resume_kind == resume_stop. If
4968 the thread already has a pending status to report, we
4969 will still report it the next time we wait - see
4970 status_pending_p_callback. */
4972 /* If we already have a pending signal to report, then
4973 there's no need to queue a SIGSTOP, as this means we're
4974 midway through moving the LWP out of the jumppad, and we
4975 will report the pending signal as soon as that is
4977 if (lwp
->pending_signals_to_report
== NULL
)
4981 /* For stop requests, we're done. */
4983 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4987 /* If this thread which is about to be resumed has a pending status,
4988 then don't resume it - we can just report the pending status.
4989 Likewise if it is suspended, because e.g., another thread is
4990 stepping past a breakpoint. Make sure to queue any signals that
4991 would otherwise be sent. In all-stop mode, we do this decision
4992 based on if *any* thread has a pending status. If there's a
4993 thread that needs the step-over-breakpoint dance, then don't
4994 resume any other thread but that particular one. */
4995 leave_pending
= (lwp
->suspended
4996 || lwp
->status_pending_p
4997 || leave_all_stopped
);
4999 /* If we have a new signal, enqueue the signal. */
5000 if (lwp
->resume
->sig
!= 0)
5002 siginfo_t info
, *info_p
;
5004 /* If this is the same signal we were previously stopped by,
5005 make sure to queue its siginfo. */
5006 if (WIFSTOPPED (lwp
->last_status
)
5007 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
5008 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
),
5009 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
5014 enqueue_pending_signal (lwp
, lwp
->resume
->sig
, info_p
);
5020 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
5022 proceed_one_lwp (thread
, NULL
);
5027 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
5030 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
5035 linux_resume (struct thread_resume
*resume_info
, size_t n
)
5037 struct thread_info
*need_step_over
= NULL
;
5042 debug_printf ("linux_resume:\n");
5045 for_each_thread ([&] (thread_info
*thread
)
5047 linux_set_resume_request (thread
, resume_info
, n
);
5050 /* If there is a thread which would otherwise be resumed, which has
5051 a pending status, then don't resume any threads - we can just
5052 report the pending status. Make sure to queue any signals that
5053 would otherwise be sent. In non-stop mode, we'll apply this
5054 logic to each thread individually. We consume all pending events
5055 before considering to start a step-over (in all-stop). */
5056 bool any_pending
= false;
5058 any_pending
= find_thread (resume_status_pending_p
) != NULL
;
5060 /* If there is a thread which would otherwise be resumed, which is
5061 stopped at a breakpoint that needs stepping over, then don't
5062 resume any threads - have it step over the breakpoint with all
5063 other threads stopped, then resume all threads again. Make sure
5064 to queue any signals that would otherwise be delivered or
5066 if (!any_pending
&& supports_breakpoints ())
5067 need_step_over
= find_thread (need_step_over_p
);
5069 bool leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
5073 if (need_step_over
!= NULL
)
5074 debug_printf ("Not resuming all, need step over\n");
5075 else if (any_pending
)
5076 debug_printf ("Not resuming, all-stop and found "
5077 "an LWP with pending status\n");
5079 debug_printf ("Resuming, no pending status or step over needed\n");
5082 /* Even if we're leaving threads stopped, queue all signals we'd
5083 otherwise deliver. */
5084 for_each_thread ([&] (thread_info
*thread
)
5086 linux_resume_one_thread (thread
, leave_all_stopped
);
5090 start_step_over (get_thread_lwp (need_step_over
));
5094 debug_printf ("linux_resume done\n");
5098 /* We may have events that were pending that can/should be sent to
5099 the client now. Trigger a linux_wait call. */
5100 if (target_is_async_p ())
5104 /* This function is called once per thread. We check the thread's
5105 last resume request, which will tell us whether to resume, step, or
5106 leave the thread stopped. Any signal the client requested to be
5107 delivered has already been enqueued at this point.
5109 If any thread that GDB wants running is stopped at an internal
5110 breakpoint that needs stepping over, we start a step-over operation
5111 on that particular thread, and leave all others stopped. */
5114 proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
5116 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5123 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
5128 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
5132 if (thread
->last_resume_kind
== resume_stop
5133 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
5136 debug_printf (" client wants LWP to remain %ld stopped\n",
5141 if (lwp
->status_pending_p
)
5144 debug_printf (" LWP %ld has pending status, leaving stopped\n",
5149 gdb_assert (lwp
->suspended
>= 0);
5154 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
5158 if (thread
->last_resume_kind
== resume_stop
5159 && lwp
->pending_signals_to_report
== NULL
5160 && (lwp
->collecting_fast_tracepoint
5161 == fast_tpoint_collect_result::not_collecting
))
5163 /* We haven't reported this LWP as stopped yet (otherwise, the
5164 last_status.kind check above would catch it, and we wouldn't
5165 reach here. This LWP may have been momentarily paused by a
5166 stop_all_lwps call while handling for example, another LWP's
5167 step-over. In that case, the pending expected SIGSTOP signal
5168 that was queued at vCont;t handling time will have already
5169 been consumed by wait_for_sigstop, and so we need to requeue
5170 another one here. Note that if the LWP already has a SIGSTOP
5171 pending, this is a no-op. */
5174 debug_printf ("Client wants LWP %ld to stop. "
5175 "Making sure it has a SIGSTOP pending\n",
5181 if (thread
->last_resume_kind
== resume_step
)
5184 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5187 /* If resume_step is requested by GDB, install single-step
5188 breakpoints when the thread is about to be actually resumed if
5189 the single-step breakpoints weren't removed. */
5190 if (can_software_single_step ()
5191 && !has_single_step_breakpoints (thread
))
5192 install_software_single_step_breakpoints (lwp
);
5194 step
= maybe_hw_step (thread
);
5196 else if (lwp
->bp_reinsert
!= 0)
5199 debug_printf (" stepping LWP %ld, reinsert set\n",
5202 step
= maybe_hw_step (thread
);
5207 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
5211 unsuspend_and_proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
5213 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5218 lwp_suspended_decr (lwp
);
5220 proceed_one_lwp (thread
, except
);
5223 /* When we finish a step-over, set threads running again. If there's
5224 another thread that may need a step-over, now's the time to start
5225 it. Eventually, we'll move all threads past their breakpoints. */
5228 proceed_all_lwps (void)
5230 struct thread_info
*need_step_over
;
5232 /* If there is a thread which would otherwise be resumed, which is
5233 stopped at a breakpoint that needs stepping over, then don't
5234 resume any threads - have it step over the breakpoint with all
5235 other threads stopped, then resume all threads again. */
5237 if (supports_breakpoints ())
5239 need_step_over
= find_thread (need_step_over_p
);
5241 if (need_step_over
!= NULL
)
5244 debug_printf ("proceed_all_lwps: found "
5245 "thread %ld needing a step-over\n",
5246 lwpid_of (need_step_over
));
5248 start_step_over (get_thread_lwp (need_step_over
));
5254 debug_printf ("Proceeding, no step-over needed\n");
5256 for_each_thread ([] (thread_info
*thread
)
5258 proceed_one_lwp (thread
, NULL
);
5262 /* Stopped LWPs that the client wanted to be running, that don't have
5263 pending statuses, are set to run again, except for EXCEPT, if not
5264 NULL. This undoes a stop_all_lwps call. */
5267 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
5273 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5274 lwpid_of (get_lwp_thread (except
)));
5276 debug_printf ("unstopping all lwps\n");
5280 for_each_thread ([&] (thread_info
*thread
)
5282 unsuspend_and_proceed_one_lwp (thread
, except
);
5285 for_each_thread ([&] (thread_info
*thread
)
5287 proceed_one_lwp (thread
, except
);
5292 debug_printf ("unstop_all_lwps done\n");
5298 #ifdef HAVE_LINUX_REGSETS
5300 #define use_linux_regsets 1
5302 /* Returns true if REGSET has been disabled. */
5305 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5307 return (info
->disabled_regsets
!= NULL
5308 && info
->disabled_regsets
[regset
- info
->regsets
]);
5311 /* Disable REGSET. */
5314 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5318 dr_offset
= regset
- info
->regsets
;
5319 if (info
->disabled_regsets
== NULL
)
5320 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5321 info
->disabled_regsets
[dr_offset
] = 1;
5325 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5326 struct regcache
*regcache
)
5328 struct regset_info
*regset
;
5329 int saw_general_regs
= 0;
5333 pid
= lwpid_of (current_thread
);
5334 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5339 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5342 buf
= xmalloc (regset
->size
);
5344 nt_type
= regset
->nt_type
;
5348 iov
.iov_len
= regset
->size
;
5349 data
= (void *) &iov
;
5355 res
= ptrace (regset
->get_request
, pid
,
5356 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5358 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5364 /* If we get EIO on a regset, do not try it again for
5365 this process mode. */
5366 disable_regset (regsets_info
, regset
);
5368 else if (errno
== ENODATA
)
5370 /* ENODATA may be returned if the regset is currently
5371 not "active". This can happen in normal operation,
5372 so suppress the warning in this case. */
5374 else if (errno
== ESRCH
)
5376 /* At this point, ESRCH should mean the process is
5377 already gone, in which case we simply ignore attempts
5378 to read its registers. */
5383 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5390 if (regset
->type
== GENERAL_REGS
)
5391 saw_general_regs
= 1;
5392 regset
->store_function (regcache
, buf
);
5396 if (saw_general_regs
)
5403 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5404 struct regcache
*regcache
)
5406 struct regset_info
*regset
;
5407 int saw_general_regs
= 0;
5411 pid
= lwpid_of (current_thread
);
5412 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5417 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5418 || regset
->fill_function
== NULL
)
5421 buf
= xmalloc (regset
->size
);
5423 /* First fill the buffer with the current register set contents,
5424 in case there are any items in the kernel's regset that are
5425 not in gdbserver's regcache. */
5427 nt_type
= regset
->nt_type
;
5431 iov
.iov_len
= regset
->size
;
5432 data
= (void *) &iov
;
5438 res
= ptrace (regset
->get_request
, pid
,
5439 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5441 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5446 /* Then overlay our cached registers on that. */
5447 regset
->fill_function (regcache
, buf
);
5449 /* Only now do we write the register set. */
5451 res
= ptrace (regset
->set_request
, pid
,
5452 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5454 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5462 /* If we get EIO on a regset, do not try it again for
5463 this process mode. */
5464 disable_regset (regsets_info
, regset
);
5466 else if (errno
== ESRCH
)
5468 /* At this point, ESRCH should mean the process is
5469 already gone, in which case we simply ignore attempts
5470 to change its registers. See also the related
5471 comment in linux_resume_one_lwp. */
5477 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5480 else if (regset
->type
== GENERAL_REGS
)
5481 saw_general_regs
= 1;
5484 if (saw_general_regs
)
5490 #else /* !HAVE_LINUX_REGSETS */
5492 #define use_linux_regsets 0
5493 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5494 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5498 /* Return 1 if register REGNO is supported by one of the regset ptrace
5499 calls or 0 if it has to be transferred individually. */
5502 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5504 unsigned char mask
= 1 << (regno
% 8);
5505 size_t index
= regno
/ 8;
5507 return (use_linux_regsets
5508 && (regs_info
->regset_bitmap
== NULL
5509 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5512 #ifdef HAVE_LINUX_USRREGS
5515 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5519 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5520 error ("Invalid register number %d.", regnum
);
5522 addr
= usrregs
->regmap
[regnum
];
5527 /* Fetch one register. */
5529 fetch_register (const struct usrregs_info
*usrregs
,
5530 struct regcache
*regcache
, int regno
)
5537 if (regno
>= usrregs
->num_regs
)
5539 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5542 regaddr
= register_addr (usrregs
, regno
);
5546 size
= ((register_size (regcache
->tdesc
, regno
)
5547 + sizeof (PTRACE_XFER_TYPE
) - 1)
5548 & -sizeof (PTRACE_XFER_TYPE
));
5549 buf
= (char *) alloca (size
);
5551 pid
= lwpid_of (current_thread
);
5552 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5555 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5556 ptrace (PTRACE_PEEKUSER
, pid
,
5557 /* Coerce to a uintptr_t first to avoid potential gcc warning
5558 of coercing an 8 byte integer to a 4 byte pointer. */
5559 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5560 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5563 /* Mark register REGNO unavailable. */
5564 supply_register (regcache
, regno
, NULL
);
5569 if (the_low_target
.supply_ptrace_register
)
5570 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5572 supply_register (regcache
, regno
, buf
);
5575 /* Store one register. */
5577 store_register (const struct usrregs_info
*usrregs
,
5578 struct regcache
*regcache
, int regno
)
5585 if (regno
>= usrregs
->num_regs
)
5587 if ((*the_low_target
.cannot_store_register
) (regno
))
5590 regaddr
= register_addr (usrregs
, regno
);
5594 size
= ((register_size (regcache
->tdesc
, regno
)
5595 + sizeof (PTRACE_XFER_TYPE
) - 1)
5596 & -sizeof (PTRACE_XFER_TYPE
));
5597 buf
= (char *) alloca (size
);
5598 memset (buf
, 0, size
);
5600 if (the_low_target
.collect_ptrace_register
)
5601 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5603 collect_register (regcache
, regno
, buf
);
5605 pid
= lwpid_of (current_thread
);
5606 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5609 ptrace (PTRACE_POKEUSER
, pid
,
5610 /* Coerce to a uintptr_t first to avoid potential gcc warning
5611 about coercing an 8 byte integer to a 4 byte pointer. */
5612 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5613 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5616 /* At this point, ESRCH should mean the process is
5617 already gone, in which case we simply ignore attempts
5618 to change its registers. See also the related
5619 comment in linux_resume_one_lwp. */
5623 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5624 error ("writing register %d: %s", regno
, strerror (errno
));
5626 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5630 /* Fetch all registers, or just one, from the child process.
5631 If REGNO is -1, do this for all registers, skipping any that are
5632 assumed to have been retrieved by regsets_fetch_inferior_registers,
5633 unless ALL is non-zero.
5634 Otherwise, REGNO specifies which register (so we can save time). */
5636 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5637 struct regcache
*regcache
, int regno
, int all
)
5639 struct usrregs_info
*usr
= regs_info
->usrregs
;
5643 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5644 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5645 fetch_register (usr
, regcache
, regno
);
5648 fetch_register (usr
, regcache
, regno
);
5651 /* Store our register values back into the inferior.
5652 If REGNO is -1, do this for all registers, skipping any that are
5653 assumed to have been saved by regsets_store_inferior_registers,
5654 unless ALL is non-zero.
5655 Otherwise, REGNO specifies which register (so we can save time). */
5657 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5658 struct regcache
*regcache
, int regno
, int all
)
5660 struct usrregs_info
*usr
= regs_info
->usrregs
;
5664 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5665 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5666 store_register (usr
, regcache
, regno
);
5669 store_register (usr
, regcache
, regno
);
5672 #else /* !HAVE_LINUX_USRREGS */
5674 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5675 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5681 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5685 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5689 if (the_low_target
.fetch_register
!= NULL
5690 && regs_info
->usrregs
!= NULL
)
5691 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5692 (*the_low_target
.fetch_register
) (regcache
, regno
);
5694 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5695 if (regs_info
->usrregs
!= NULL
)
5696 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5700 if (the_low_target
.fetch_register
!= NULL
5701 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5704 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5706 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5708 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5709 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5714 linux_store_registers (struct regcache
*regcache
, int regno
)
5718 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5722 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5724 if (regs_info
->usrregs
!= NULL
)
5725 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5729 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5731 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5733 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5734 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5739 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5740 to debugger memory starting at MYADDR. */
5743 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5745 int pid
= lwpid_of (current_thread
);
5746 PTRACE_XFER_TYPE
*buffer
;
5754 /* Try using /proc. Don't bother for one word. */
5755 if (len
>= 3 * sizeof (long))
5759 /* We could keep this file open and cache it - possibly one per
5760 thread. That requires some juggling, but is even faster. */
5761 sprintf (filename
, "/proc/%d/mem", pid
);
5762 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5766 /* If pread64 is available, use it. It's faster if the kernel
5767 supports it (only one syscall), and it's 64-bit safe even on
5768 32-bit platforms (for instance, SPARC debugging a SPARC64
5771 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5774 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5775 bytes
= read (fd
, myaddr
, len
);
5782 /* Some data was read, we'll try to get the rest with ptrace. */
5792 /* Round starting address down to longword boundary. */
5793 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5794 /* Round ending address up; get number of longwords that makes. */
5795 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5796 / sizeof (PTRACE_XFER_TYPE
));
5797 /* Allocate buffer of that many longwords. */
5798 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5800 /* Read all the longwords */
5802 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5804 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5805 about coercing an 8 byte integer to a 4 byte pointer. */
5806 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5807 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5808 (PTRACE_TYPE_ARG4
) 0);
5814 /* Copy appropriate bytes out of the buffer. */
5817 i
*= sizeof (PTRACE_XFER_TYPE
);
5818 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5820 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5827 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5828 memory at MEMADDR. On failure (cannot write to the inferior)
5829 returns the value of errno. Always succeeds if LEN is zero. */
5832 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5835 /* Round starting address down to longword boundary. */
5836 CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5837 /* Round ending address up; get number of longwords that makes. */
5839 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5840 / sizeof (PTRACE_XFER_TYPE
);
5842 /* Allocate buffer of that many longwords. */
5843 PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5845 int pid
= lwpid_of (current_thread
);
5849 /* Zero length write always succeeds. */
5855 /* Dump up to four bytes. */
5856 char str
[4 * 2 + 1];
5858 int dump
= len
< 4 ? len
: 4;
5860 for (i
= 0; i
< dump
; i
++)
5862 sprintf (p
, "%02x", myaddr
[i
]);
5867 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5868 str
, (long) memaddr
, pid
);
5871 /* Fill start and end extra bytes of buffer with existing memory data. */
5874 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5875 about coercing an 8 byte integer to a 4 byte pointer. */
5876 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5877 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5878 (PTRACE_TYPE_ARG4
) 0);
5886 = ptrace (PTRACE_PEEKTEXT
, pid
,
5887 /* Coerce to a uintptr_t first to avoid potential gcc warning
5888 about coercing an 8 byte integer to a 4 byte pointer. */
5889 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5890 * sizeof (PTRACE_XFER_TYPE
)),
5891 (PTRACE_TYPE_ARG4
) 0);
5896 /* Copy data to be written over corresponding part of buffer. */
5898 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5901 /* Write the entire buffer. */
5903 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5906 ptrace (PTRACE_POKETEXT
, pid
,
5907 /* Coerce to a uintptr_t first to avoid potential gcc warning
5908 about coercing an 8 byte integer to a 4 byte pointer. */
5909 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5910 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5919 linux_look_up_symbols (void)
5921 #ifdef USE_THREAD_DB
5922 struct process_info
*proc
= current_process ();
5924 if (proc
->priv
->thread_db
!= NULL
)
5932 linux_request_interrupt (void)
5934 /* Send a SIGINT to the process group. This acts just like the user
5935 typed a ^C on the controlling terminal. */
5936 kill (-signal_pid
, SIGINT
);
5939 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5940 to debugger memory starting at MYADDR. */
5943 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5945 char filename
[PATH_MAX
];
5947 int pid
= lwpid_of (current_thread
);
5949 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5951 fd
= open (filename
, O_RDONLY
);
5955 if (offset
!= (CORE_ADDR
) 0
5956 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5959 n
= read (fd
, myaddr
, len
);
5966 /* These breakpoint and watchpoint related wrapper functions simply
5967 pass on the function call if the target has registered a
5968 corresponding function. */
5971 linux_supports_z_point_type (char z_type
)
5973 return (the_low_target
.supports_z_point_type
!= NULL
5974 && the_low_target
.supports_z_point_type (z_type
));
5978 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5979 int size
, struct raw_breakpoint
*bp
)
5981 if (type
== raw_bkpt_type_sw
)
5982 return insert_memory_breakpoint (bp
);
5983 else if (the_low_target
.insert_point
!= NULL
)
5984 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5986 /* Unsupported (see target.h). */
5991 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5992 int size
, struct raw_breakpoint
*bp
)
5994 if (type
== raw_bkpt_type_sw
)
5995 return remove_memory_breakpoint (bp
);
5996 else if (the_low_target
.remove_point
!= NULL
)
5997 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5999 /* Unsupported (see target.h). */
6003 /* Implement the to_stopped_by_sw_breakpoint target_ops
6007 linux_stopped_by_sw_breakpoint (void)
6009 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6011 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
6014 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
6018 linux_supports_stopped_by_sw_breakpoint (void)
6020 return USE_SIGTRAP_SIGINFO
;
6023 /* Implement the to_stopped_by_hw_breakpoint target_ops
6027 linux_stopped_by_hw_breakpoint (void)
6029 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6031 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
6034 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
6038 linux_supports_stopped_by_hw_breakpoint (void)
6040 return USE_SIGTRAP_SIGINFO
;
6043 /* Implement the supports_hardware_single_step target_ops method. */
6046 linux_supports_hardware_single_step (void)
6048 return can_hardware_single_step ();
6052 linux_supports_software_single_step (void)
6054 return can_software_single_step ();
6058 linux_stopped_by_watchpoint (void)
6060 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6062 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
6066 linux_stopped_data_address (void)
6068 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6070 return lwp
->stopped_data_address
;
6073 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6074 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6075 && defined(PT_TEXT_END_ADDR)
6077 /* This is only used for targets that define PT_TEXT_ADDR,
6078 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
6079 the target has different ways of acquiring this information, like
6082 /* Under uClinux, programs are loaded at non-zero offsets, which we need
6083 to tell gdb about. */
6086 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
6088 unsigned long text
, text_end
, data
;
6089 int pid
= lwpid_of (current_thread
);
6093 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
6094 (PTRACE_TYPE_ARG4
) 0);
6095 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
6096 (PTRACE_TYPE_ARG4
) 0);
6097 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
6098 (PTRACE_TYPE_ARG4
) 0);
6102 /* Both text and data offsets produced at compile-time (and so
6103 used by gdb) are relative to the beginning of the program,
6104 with the data segment immediately following the text segment.
6105 However, the actual runtime layout in memory may put the data
6106 somewhere else, so when we send gdb a data base-address, we
6107 use the real data base address and subtract the compile-time
6108 data base-address from it (which is just the length of the
6109 text segment). BSS immediately follows data in both
6112 *data_p
= data
- (text_end
- text
);
6121 linux_qxfer_osdata (const char *annex
,
6122 unsigned char *readbuf
, unsigned const char *writebuf
,
6123 CORE_ADDR offset
, int len
)
6125 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
6128 /* Convert a native/host siginfo object, into/from the siginfo in the
6129 layout of the inferiors' architecture. */
6132 siginfo_fixup (siginfo_t
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
6136 if (the_low_target
.siginfo_fixup
!= NULL
)
6137 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
6139 /* If there was no callback, or the callback didn't do anything,
6140 then just do a straight memcpy. */
6144 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
6146 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
6151 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
6152 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
6156 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
6158 if (current_thread
== NULL
)
6161 pid
= lwpid_of (current_thread
);
6164 debug_printf ("%s siginfo for lwp %d.\n",
6165 readbuf
!= NULL
? "Reading" : "Writing",
6168 if (offset
>= sizeof (siginfo
))
6171 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6174 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6175 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6176 inferior with a 64-bit GDBSERVER should look the same as debugging it
6177 with a 32-bit GDBSERVER, we need to convert it. */
6178 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
6180 if (offset
+ len
> sizeof (siginfo
))
6181 len
= sizeof (siginfo
) - offset
;
6183 if (readbuf
!= NULL
)
6184 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6187 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6189 /* Convert back to ptrace layout before flushing it out. */
6190 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6192 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6199 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6200 so we notice when children change state; as the handler for the
6201 sigsuspend in my_waitpid. */
6204 sigchld_handler (int signo
)
6206 int old_errno
= errno
;
6212 /* fprintf is not async-signal-safe, so call write
6214 if (write (2, "sigchld_handler\n",
6215 sizeof ("sigchld_handler\n") - 1) < 0)
6216 break; /* just ignore */
6220 if (target_is_async_p ())
6221 async_file_mark (); /* trigger a linux_wait */
6227 linux_supports_non_stop (void)
6233 linux_async (int enable
)
6235 int previous
= target_is_async_p ();
6238 debug_printf ("linux_async (%d), previous=%d\n",
6241 if (previous
!= enable
)
6244 sigemptyset (&mask
);
6245 sigaddset (&mask
, SIGCHLD
);
6247 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
6251 if (pipe (linux_event_pipe
) == -1)
6253 linux_event_pipe
[0] = -1;
6254 linux_event_pipe
[1] = -1;
6255 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6257 warning ("creating event pipe failed.");
6261 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6262 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6264 /* Register the event loop handler. */
6265 add_file_handler (linux_event_pipe
[0],
6266 handle_target_event
, NULL
);
6268 /* Always trigger a linux_wait. */
6273 delete_file_handler (linux_event_pipe
[0]);
6275 close (linux_event_pipe
[0]);
6276 close (linux_event_pipe
[1]);
6277 linux_event_pipe
[0] = -1;
6278 linux_event_pipe
[1] = -1;
6281 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6288 linux_start_non_stop (int nonstop
)
6290 /* Register or unregister from event-loop accordingly. */
6291 linux_async (nonstop
);
6293 if (target_is_async_p () != (nonstop
!= 0))
6300 linux_supports_multi_process (void)
6305 /* Check if fork events are supported. */
6308 linux_supports_fork_events (void)
6310 return linux_supports_tracefork ();
6313 /* Check if vfork events are supported. */
6316 linux_supports_vfork_events (void)
6318 return linux_supports_tracefork ();
6321 /* Check if exec events are supported. */
6324 linux_supports_exec_events (void)
6326 return linux_supports_traceexec ();
6329 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6330 ptrace flags for all inferiors. This is in case the new GDB connection
6331 doesn't support the same set of events that the previous one did. */
6334 linux_handle_new_gdb_connection (void)
6336 /* Request that all the lwps reset their ptrace options. */
6337 for_each_thread ([] (thread_info
*thread
)
6339 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6343 /* Stop the lwp so we can modify its ptrace options. */
6344 lwp
->must_set_ptrace_flags
= 1;
6345 linux_stop_lwp (lwp
);
6349 /* Already stopped; go ahead and set the ptrace options. */
6350 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6351 int options
= linux_low_ptrace_options (proc
->attached
);
6353 linux_enable_event_reporting (lwpid_of (thread
), options
);
6354 lwp
->must_set_ptrace_flags
= 0;
6360 linux_supports_disable_randomization (void)
6362 #ifdef HAVE_PERSONALITY
6370 linux_supports_agent (void)
6376 linux_supports_range_stepping (void)
6378 if (can_software_single_step ())
6380 if (*the_low_target
.supports_range_stepping
== NULL
)
6383 return (*the_low_target
.supports_range_stepping
) ();
6386 /* Enumerate spufs IDs for process PID. */
6388 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6394 struct dirent
*entry
;
6396 sprintf (path
, "/proc/%ld/fd", pid
);
6397 dir
= opendir (path
);
6402 while ((entry
= readdir (dir
)) != NULL
)
6408 fd
= atoi (entry
->d_name
);
6412 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6413 if (stat (path
, &st
) != 0)
6415 if (!S_ISDIR (st
.st_mode
))
6418 if (statfs (path
, &stfs
) != 0)
6420 if (stfs
.f_type
!= SPUFS_MAGIC
)
6423 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6425 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6435 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6436 object type, using the /proc file system. */
6438 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6439 unsigned const char *writebuf
,
6440 CORE_ADDR offset
, int len
)
6442 long pid
= lwpid_of (current_thread
);
6447 if (!writebuf
&& !readbuf
)
6455 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6458 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6459 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6464 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6471 ret
= write (fd
, writebuf
, (size_t) len
);
6473 ret
= read (fd
, readbuf
, (size_t) len
);
6479 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6480 struct target_loadseg
6482 /* Core address to which the segment is mapped. */
6484 /* VMA recorded in the program header. */
6486 /* Size of this segment in memory. */
6490 # if defined PT_GETDSBT
6491 struct target_loadmap
6493 /* Protocol version number, must be zero. */
6495 /* Pointer to the DSBT table, its size, and the DSBT index. */
6496 unsigned *dsbt_table
;
6497 unsigned dsbt_size
, dsbt_index
;
6498 /* Number of segments in this map. */
6500 /* The actual memory map. */
6501 struct target_loadseg segs
[/*nsegs*/];
6503 # define LINUX_LOADMAP PT_GETDSBT
6504 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6505 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6507 struct target_loadmap
6509 /* Protocol version number, must be zero. */
6511 /* Number of segments in this map. */
6513 /* The actual memory map. */
6514 struct target_loadseg segs
[/*nsegs*/];
6516 # define LINUX_LOADMAP PTRACE_GETFDPIC
6517 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6518 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6522 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6523 unsigned char *myaddr
, unsigned int len
)
6525 int pid
= lwpid_of (current_thread
);
6527 struct target_loadmap
*data
= NULL
;
6528 unsigned int actual_length
, copy_length
;
6530 if (strcmp (annex
, "exec") == 0)
6531 addr
= (int) LINUX_LOADMAP_EXEC
;
6532 else if (strcmp (annex
, "interp") == 0)
6533 addr
= (int) LINUX_LOADMAP_INTERP
;
6537 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6543 actual_length
= sizeof (struct target_loadmap
)
6544 + sizeof (struct target_loadseg
) * data
->nsegs
;
6546 if (offset
< 0 || offset
> actual_length
)
6549 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6550 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6554 # define linux_read_loadmap NULL
6555 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6558 linux_process_qsupported (char **features
, int count
)
6560 if (the_low_target
.process_qsupported
!= NULL
)
6561 the_low_target
.process_qsupported (features
, count
);
6565 linux_supports_catch_syscall (void)
6567 return (the_low_target
.get_syscall_trapinfo
!= NULL
6568 && linux_supports_tracesysgood ());
6572 linux_get_ipa_tdesc_idx (void)
6574 if (the_low_target
.get_ipa_tdesc_idx
== NULL
)
6577 return (*the_low_target
.get_ipa_tdesc_idx
) ();
6581 linux_supports_tracepoints (void)
6583 if (*the_low_target
.supports_tracepoints
== NULL
)
6586 return (*the_low_target
.supports_tracepoints
) ();
6590 linux_read_pc (struct regcache
*regcache
)
6592 if (the_low_target
.get_pc
== NULL
)
6595 return (*the_low_target
.get_pc
) (regcache
);
6599 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6601 gdb_assert (the_low_target
.set_pc
!= NULL
);
6603 (*the_low_target
.set_pc
) (regcache
, pc
);
6607 linux_thread_stopped (struct thread_info
*thread
)
6609 return get_thread_lwp (thread
)->stopped
;
6612 /* This exposes stop-all-threads functionality to other modules. */
6615 linux_pause_all (int freeze
)
6617 stop_all_lwps (freeze
, NULL
);
6620 /* This exposes unstop-all-threads functionality to other gdbserver
6624 linux_unpause_all (int unfreeze
)
6626 unstop_all_lwps (unfreeze
, NULL
);
6630 linux_prepare_to_access_memory (void)
6632 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6635 linux_pause_all (1);
6640 linux_done_accessing_memory (void)
6642 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6645 linux_unpause_all (1);
6649 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6650 CORE_ADDR collector
,
6653 CORE_ADDR
*jump_entry
,
6654 CORE_ADDR
*trampoline
,
6655 ULONGEST
*trampoline_size
,
6656 unsigned char *jjump_pad_insn
,
6657 ULONGEST
*jjump_pad_insn_size
,
6658 CORE_ADDR
*adjusted_insn_addr
,
6659 CORE_ADDR
*adjusted_insn_addr_end
,
6662 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6663 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6664 jump_entry
, trampoline
, trampoline_size
,
6665 jjump_pad_insn
, jjump_pad_insn_size
,
6666 adjusted_insn_addr
, adjusted_insn_addr_end
,
6670 static struct emit_ops
*
6671 linux_emit_ops (void)
6673 if (the_low_target
.emit_ops
!= NULL
)
6674 return (*the_low_target
.emit_ops
) ();
6680 linux_get_min_fast_tracepoint_insn_len (void)
6682 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6685 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6688 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6689 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6691 char filename
[PATH_MAX
];
6693 const int auxv_size
= is_elf64
6694 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6695 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6697 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6699 fd
= open (filename
, O_RDONLY
);
6705 while (read (fd
, buf
, auxv_size
) == auxv_size
6706 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6710 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6712 switch (aux
->a_type
)
6715 *phdr_memaddr
= aux
->a_un
.a_val
;
6718 *num_phdr
= aux
->a_un
.a_val
;
6724 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6726 switch (aux
->a_type
)
6729 *phdr_memaddr
= aux
->a_un
.a_val
;
6732 *num_phdr
= aux
->a_un
.a_val
;
6740 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6742 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6743 "phdr_memaddr = %ld, phdr_num = %d",
6744 (long) *phdr_memaddr
, *num_phdr
);
6751 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6754 get_dynamic (const int pid
, const int is_elf64
)
6756 CORE_ADDR phdr_memaddr
, relocation
;
6758 unsigned char *phdr_buf
;
6759 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6761 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6764 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6765 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6767 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6770 /* Compute relocation: it is expected to be 0 for "regular" executables,
6771 non-zero for PIE ones. */
6773 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6776 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6778 if (p
->p_type
== PT_PHDR
)
6779 relocation
= phdr_memaddr
- p
->p_vaddr
;
6783 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6785 if (p
->p_type
== PT_PHDR
)
6786 relocation
= phdr_memaddr
- p
->p_vaddr
;
6789 if (relocation
== -1)
6791 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6792 any real world executables, including PIE executables, have always
6793 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6794 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6795 or present DT_DEBUG anyway (fpc binaries are statically linked).
6797 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6799 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6804 for (i
= 0; i
< num_phdr
; i
++)
6808 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6810 if (p
->p_type
== PT_DYNAMIC
)
6811 return p
->p_vaddr
+ relocation
;
6815 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6817 if (p
->p_type
== PT_DYNAMIC
)
6818 return p
->p_vaddr
+ relocation
;
6825 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6826 can be 0 if the inferior does not yet have the library list initialized.
6827 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6828 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6831 get_r_debug (const int pid
, const int is_elf64
)
6833 CORE_ADDR dynamic_memaddr
;
6834 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6835 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6838 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6839 if (dynamic_memaddr
== 0)
6842 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6846 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6847 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6851 unsigned char buf
[sizeof (Elf64_Xword
)];
6855 #ifdef DT_MIPS_RLD_MAP
6856 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6858 if (linux_read_memory (dyn
->d_un
.d_val
,
6859 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6864 #endif /* DT_MIPS_RLD_MAP */
6865 #ifdef DT_MIPS_RLD_MAP_REL
6866 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6868 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6869 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6874 #endif /* DT_MIPS_RLD_MAP_REL */
6876 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6877 map
= dyn
->d_un
.d_val
;
6879 if (dyn
->d_tag
== DT_NULL
)
6884 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6885 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6889 unsigned char buf
[sizeof (Elf32_Word
)];
6893 #ifdef DT_MIPS_RLD_MAP
6894 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6896 if (linux_read_memory (dyn
->d_un
.d_val
,
6897 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6902 #endif /* DT_MIPS_RLD_MAP */
6903 #ifdef DT_MIPS_RLD_MAP_REL
6904 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6906 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6907 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6912 #endif /* DT_MIPS_RLD_MAP_REL */
6914 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6915 map
= dyn
->d_un
.d_val
;
6917 if (dyn
->d_tag
== DT_NULL
)
6921 dynamic_memaddr
+= dyn_size
;
6927 /* Read one pointer from MEMADDR in the inferior. */
6930 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6934 /* Go through a union so this works on either big or little endian
6935 hosts, when the inferior's pointer size is smaller than the size
6936 of CORE_ADDR. It is assumed the inferior's endianness is the
6937 same of the superior's. */
6940 CORE_ADDR core_addr
;
6945 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6948 if (ptr_size
== sizeof (CORE_ADDR
))
6949 *ptr
= addr
.core_addr
;
6950 else if (ptr_size
== sizeof (unsigned int))
6953 gdb_assert_not_reached ("unhandled pointer size");
6958 struct link_map_offsets
6960 /* Offset and size of r_debug.r_version. */
6961 int r_version_offset
;
6963 /* Offset and size of r_debug.r_map. */
6966 /* Offset to l_addr field in struct link_map. */
6969 /* Offset to l_name field in struct link_map. */
6972 /* Offset to l_ld field in struct link_map. */
6975 /* Offset to l_next field in struct link_map. */
6978 /* Offset to l_prev field in struct link_map. */
6982 /* Construct qXfer:libraries-svr4:read reply. */
6985 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6986 unsigned const char *writebuf
,
6987 CORE_ADDR offset
, int len
)
6989 struct process_info_private
*const priv
= current_process ()->priv
;
6990 char filename
[PATH_MAX
];
6993 static const struct link_map_offsets lmo_32bit_offsets
=
6995 0, /* r_version offset. */
6996 4, /* r_debug.r_map offset. */
6997 0, /* l_addr offset in link_map. */
6998 4, /* l_name offset in link_map. */
6999 8, /* l_ld offset in link_map. */
7000 12, /* l_next offset in link_map. */
7001 16 /* l_prev offset in link_map. */
7004 static const struct link_map_offsets lmo_64bit_offsets
=
7006 0, /* r_version offset. */
7007 8, /* r_debug.r_map offset. */
7008 0, /* l_addr offset in link_map. */
7009 8, /* l_name offset in link_map. */
7010 16, /* l_ld offset in link_map. */
7011 24, /* l_next offset in link_map. */
7012 32 /* l_prev offset in link_map. */
7014 const struct link_map_offsets
*lmo
;
7015 unsigned int machine
;
7017 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
7018 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
7019 int header_done
= 0;
7021 if (writebuf
!= NULL
)
7023 if (readbuf
== NULL
)
7026 pid
= lwpid_of (current_thread
);
7027 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
7028 is_elf64
= elf_64_file_p (filename
, &machine
);
7029 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
7030 ptr_size
= is_elf64
? 8 : 4;
7032 while (annex
[0] != '\0')
7038 sep
= strchr (annex
, '=');
7042 name_len
= sep
- annex
;
7043 if (name_len
== 5 && startswith (annex
, "start"))
7045 else if (name_len
== 4 && startswith (annex
, "prev"))
7049 annex
= strchr (sep
, ';');
7056 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
7063 if (priv
->r_debug
== 0)
7064 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
7066 /* We failed to find DT_DEBUG. Such situation will not change
7067 for this inferior - do not retry it. Report it to GDB as
7068 E01, see for the reasons at the GDB solib-svr4.c side. */
7069 if (priv
->r_debug
== (CORE_ADDR
) -1)
7072 if (priv
->r_debug
!= 0)
7074 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
7075 (unsigned char *) &r_version
,
7076 sizeof (r_version
)) != 0
7079 warning ("unexpected r_debug version %d", r_version
);
7081 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
7082 &lm_addr
, ptr_size
) != 0)
7084 warning ("unable to read r_map from 0x%lx",
7085 (long) priv
->r_debug
+ lmo
->r_map_offset
);
7090 std::string document
= "<library-list-svr4 version=\"1.0\"";
7093 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
7094 &l_name
, ptr_size
) == 0
7095 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
7096 &l_addr
, ptr_size
) == 0
7097 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
7098 &l_ld
, ptr_size
) == 0
7099 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
7100 &l_prev
, ptr_size
) == 0
7101 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
7102 &l_next
, ptr_size
) == 0)
7104 unsigned char libname
[PATH_MAX
];
7106 if (lm_prev
!= l_prev
)
7108 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
7109 (long) lm_prev
, (long) l_prev
);
7113 /* Ignore the first entry even if it has valid name as the first entry
7114 corresponds to the main executable. The first entry should not be
7115 skipped if the dynamic loader was loaded late by a static executable
7116 (see solib-svr4.c parameter ignore_first). But in such case the main
7117 executable does not have PT_DYNAMIC present and this function already
7118 exited above due to failed get_r_debug. */
7120 string_appendf (document
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
7123 /* Not checking for error because reading may stop before
7124 we've got PATH_MAX worth of characters. */
7126 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
7127 libname
[sizeof (libname
) - 1] = '\0';
7128 if (libname
[0] != '\0')
7132 /* Terminate `<library-list-svr4'. */
7137 string_appendf (document
, "<library name=\"");
7138 xml_escape_text_append (&document
, (char *) libname
);
7139 string_appendf (document
, "\" lm=\"0x%lx\" "
7140 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
7141 (unsigned long) lm_addr
, (unsigned long) l_addr
,
7142 (unsigned long) l_ld
);
7152 /* Empty list; terminate `<library-list-svr4'. */
7156 document
+= "</library-list-svr4>";
7158 int document_len
= document
.length ();
7159 if (offset
< document_len
)
7160 document_len
-= offset
;
7163 if (len
> document_len
)
7166 memcpy (readbuf
, document
.data () + offset
, len
);
7171 #ifdef HAVE_LINUX_BTRACE
7173 /* See to_disable_btrace target method. */
7176 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
7178 enum btrace_error err
;
7180 err
= linux_disable_btrace (tinfo
);
7181 return (err
== BTRACE_ERR_NONE
? 0 : -1);
7184 /* Encode an Intel Processor Trace configuration. */
7187 linux_low_encode_pt_config (struct buffer
*buffer
,
7188 const struct btrace_data_pt_config
*config
)
7190 buffer_grow_str (buffer
, "<pt-config>\n");
7192 switch (config
->cpu
.vendor
)
7195 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7196 "model=\"%u\" stepping=\"%u\"/>\n",
7197 config
->cpu
.family
, config
->cpu
.model
,
7198 config
->cpu
.stepping
);
7205 buffer_grow_str (buffer
, "</pt-config>\n");
7208 /* Encode a raw buffer. */
7211 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
7217 /* We use hex encoding - see common/rsp-low.h. */
7218 buffer_grow_str (buffer
, "<raw>\n");
7224 elem
[0] = tohex ((*data
>> 4) & 0xf);
7225 elem
[1] = tohex (*data
++ & 0xf);
7227 buffer_grow (buffer
, elem
, 2);
7230 buffer_grow_str (buffer
, "</raw>\n");
7233 /* See to_read_btrace target method. */
7236 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
7237 enum btrace_read_type type
)
7239 struct btrace_data btrace
;
7240 struct btrace_block
*block
;
7241 enum btrace_error err
;
7244 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7245 if (err
!= BTRACE_ERR_NONE
)
7247 if (err
== BTRACE_ERR_OVERFLOW
)
7248 buffer_grow_str0 (buffer
, "E.Overflow.");
7250 buffer_grow_str0 (buffer
, "E.Generic Error.");
7255 switch (btrace
.format
)
7257 case BTRACE_FORMAT_NONE
:
7258 buffer_grow_str0 (buffer
, "E.No Trace.");
7261 case BTRACE_FORMAT_BTS
:
7262 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7263 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7266 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
7268 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7269 paddress (block
->begin
), paddress (block
->end
));
7271 buffer_grow_str0 (buffer
, "</btrace>\n");
7274 case BTRACE_FORMAT_PT
:
7275 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7276 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7277 buffer_grow_str (buffer
, "<pt>\n");
7279 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7281 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7282 btrace
.variant
.pt
.size
);
7284 buffer_grow_str (buffer
, "</pt>\n");
7285 buffer_grow_str0 (buffer
, "</btrace>\n");
7289 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7296 /* See to_btrace_conf target method. */
7299 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
7300 struct buffer
*buffer
)
7302 const struct btrace_config
*conf
;
7304 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7305 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7307 conf
= linux_btrace_conf (tinfo
);
7310 switch (conf
->format
)
7312 case BTRACE_FORMAT_NONE
:
7315 case BTRACE_FORMAT_BTS
:
7316 buffer_xml_printf (buffer
, "<bts");
7317 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7318 buffer_xml_printf (buffer
, " />\n");
7321 case BTRACE_FORMAT_PT
:
7322 buffer_xml_printf (buffer
, "<pt");
7323 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7324 buffer_xml_printf (buffer
, "/>\n");
7329 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7332 #endif /* HAVE_LINUX_BTRACE */
7334 /* See nat/linux-nat.h. */
7337 current_lwp_ptid (void)
7339 return ptid_of (current_thread
);
7342 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7345 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7347 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7348 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7350 return default_breakpoint_kind_from_pc (pcptr
);
7353 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7355 static const gdb_byte
*
7356 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7358 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7360 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7363 /* Implementation of the target_ops method
7364 "breakpoint_kind_from_current_state". */
7367 linux_breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
)
7369 if (the_low_target
.breakpoint_kind_from_current_state
!= NULL
)
7370 return (*the_low_target
.breakpoint_kind_from_current_state
) (pcptr
);
7372 return linux_breakpoint_kind_from_pc (pcptr
);
7375 /* Default implementation of linux_target_ops method "set_pc" for
7376 32-bit pc register which is literally named "pc". */
7379 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7381 uint32_t newpc
= pc
;
7383 supply_register_by_name (regcache
, "pc", &newpc
);
7386 /* Default implementation of linux_target_ops method "get_pc" for
7387 32-bit pc register which is literally named "pc". */
7390 linux_get_pc_32bit (struct regcache
*regcache
)
7394 collect_register_by_name (regcache
, "pc", &pc
);
7396 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7400 /* Default implementation of linux_target_ops method "set_pc" for
7401 64-bit pc register which is literally named "pc". */
7404 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7406 uint64_t newpc
= pc
;
7408 supply_register_by_name (regcache
, "pc", &newpc
);
7411 /* Default implementation of linux_target_ops method "get_pc" for
7412 64-bit pc register which is literally named "pc". */
7415 linux_get_pc_64bit (struct regcache
*regcache
)
7419 collect_register_by_name (regcache
, "pc", &pc
);
7421 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7426 static struct target_ops linux_target_ops
= {
7427 linux_create_inferior
,
7428 linux_post_create_inferior
,
7437 linux_fetch_registers
,
7438 linux_store_registers
,
7439 linux_prepare_to_access_memory
,
7440 linux_done_accessing_memory
,
7443 linux_look_up_symbols
,
7444 linux_request_interrupt
,
7446 linux_supports_z_point_type
,
7449 linux_stopped_by_sw_breakpoint
,
7450 linux_supports_stopped_by_sw_breakpoint
,
7451 linux_stopped_by_hw_breakpoint
,
7452 linux_supports_stopped_by_hw_breakpoint
,
7453 linux_supports_hardware_single_step
,
7454 linux_stopped_by_watchpoint
,
7455 linux_stopped_data_address
,
7456 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7457 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7458 && defined(PT_TEXT_END_ADDR)
7463 #ifdef USE_THREAD_DB
7464 thread_db_get_tls_address
,
7469 hostio_last_error_from_errno
,
7472 linux_supports_non_stop
,
7474 linux_start_non_stop
,
7475 linux_supports_multi_process
,
7476 linux_supports_fork_events
,
7477 linux_supports_vfork_events
,
7478 linux_supports_exec_events
,
7479 linux_handle_new_gdb_connection
,
7480 #ifdef USE_THREAD_DB
7481 thread_db_handle_monitor_command
,
7485 linux_common_core_of_thread
,
7487 linux_process_qsupported
,
7488 linux_supports_tracepoints
,
7491 linux_thread_stopped
,
7495 linux_stabilize_threads
,
7496 linux_install_fast_tracepoint_jump_pad
,
7498 linux_supports_disable_randomization
,
7499 linux_get_min_fast_tracepoint_insn_len
,
7500 linux_qxfer_libraries_svr4
,
7501 linux_supports_agent
,
7502 #ifdef HAVE_LINUX_BTRACE
7503 linux_enable_btrace
,
7504 linux_low_disable_btrace
,
7505 linux_low_read_btrace
,
7506 linux_low_btrace_conf
,
7513 linux_supports_range_stepping
,
7514 linux_proc_pid_to_exec_file
,
7515 linux_mntns_open_cloexec
,
7517 linux_mntns_readlink
,
7518 linux_breakpoint_kind_from_pc
,
7519 linux_sw_breakpoint_from_kind
,
7520 linux_proc_tid_get_name
,
7521 linux_breakpoint_kind_from_current_state
,
7522 linux_supports_software_single_step
,
7523 linux_supports_catch_syscall
,
7524 linux_get_ipa_tdesc_idx
,
7526 thread_db_thread_handle
,
7532 #ifdef HAVE_LINUX_REGSETS
7534 initialize_regsets_info (struct regsets_info
*info
)
7536 for (info
->num_regsets
= 0;
7537 info
->regsets
[info
->num_regsets
].size
>= 0;
7538 info
->num_regsets
++)
7544 initialize_low (void)
7546 struct sigaction sigchld_action
;
7548 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7549 set_target_ops (&linux_target_ops
);
7551 linux_ptrace_init_warnings ();
7552 linux_proc_init_warnings ();
7554 sigchld_action
.sa_handler
= sigchld_handler
;
7555 sigemptyset (&sigchld_action
.sa_mask
);
7556 sigchld_action
.sa_flags
= SA_RESTART
;
7557 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7559 initialize_low_arch ();
7561 linux_check_ptrace_features ();