+++ /dev/null
-/* Return backtrace of current program state.
- Copyright (C) 1998-2021 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <https://www.gnu.org/licenses/>. */
-
-#include <execinfo.h>
-#include <stddef.h>
-#include <string.h>
-#include <signal.h>
-#include <libc-vdso.h>
-
-/* This is the stack layout we see with every stack frame.
- Note that every routine is required by the ABI to lay out the stack
- like this.
-
- +----------------+ +-----------------+
- %r1 -> | %r1 last frame--------> | %r1 last frame--->... --> NULL
- | | | |
- | (unused) | | return address |
- +----------------+ +-----------------+
-*/
-struct layout
-{
- struct layout *next;
- void *return_address;
-};
-
-#define SIGNAL_FRAMESIZE 64
-
-/* Since the signal handler is just like any other function it needs to
- save/restore its LR and it will save it into callers stack frame.
- Since a signal handler doesn't have a caller, the kernel creates a
- dummy frame to make it look like it has a caller. */
-struct signal_frame_32 {
- char dummy[SIGNAL_FRAMESIZE];
- struct sigcontext sctx;
- mcontext_t mctx;
- /* We don't care about the rest, since IP value is at 'mctx' field. */
-};
-
-static inline bool
-is_sigtramp_address (void *nip)
-{
-#ifdef HAVE_SIGTRAMP_RT32
- if (nip == GLRO (dl_vdso_sigtramp_32))
- return true;
-#endif
- return false;
-}
-
-struct rt_signal_frame_32 {
- char dummy[SIGNAL_FRAMESIZE + 16];
- siginfo_t info;
- ucontext_t uc;
- /* We don't care about the rest, since IP value is at 'uc' field. */
-};
-
-static inline bool
-is_sigtramp_address_rt (void * nip)
-{
-#ifdef HAVE_SIGTRAMP_32
- if (nip == GLRO (dl_vdso_sigtramp_rt32))
- return true;
-#endif
- return false;
-}
-
-int
-__backtrace (void **array, int size)
-{
- struct layout *current;
- int count;
-
- /* Force gcc to spill LR. */
- asm volatile ("" : "=l"(current));
-
- /* Get the address on top-of-stack. */
- asm volatile ("lwz %0,0(1)" : "=r"(current));
-
- for ( count = 0;
- current != NULL && count < size;
- current = current->next, count++)
- {
- gregset_t *gregset = NULL;
-
- array[count] = current->return_address;
-
- /* Check if the symbol is the signal trampoline and get the interrupted
- * symbol address from the trampoline saved area. */
- if (is_sigtramp_address (current->return_address))
- {
- struct signal_frame_32 *sigframe =
- (struct signal_frame_32*) current;
- gregset = &sigframe->mctx.gregs;
- }
- else if (is_sigtramp_address_rt (current->return_address))
- {
- struct rt_signal_frame_32 *sigframe =
- (struct rt_signal_frame_32*) current;
- gregset = &sigframe->uc.uc_mcontext.uc_regs->gregs;
- }
- if (gregset)
- {
- if (count + 1 == size)
- break;
- array[++count] = (void*)((*gregset)[PT_NIP]);
- current = (void*)((*gregset)[PT_R1]);
- }
- }
-
- /* It's possible the second-last stack frame can't return
- (that is, it's __libc_start_main), in which case
- the CRT startup code will have set its LR to 'NULL'. */
- if (count > 0 && array[count-1] == NULL)
- count--;
-
- return count;
-}
-weak_alias (__backtrace, backtrace)
-libc_hidden_def (__backtrace)
+++ /dev/null
-/* Return backtrace of current program state.
- Copyright (C) 1998-2021 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Library General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Library General Public License for more details.
-
- You should have received a copy of the GNU Library General Public
- License along with the GNU C Library; see the file COPYING.LIB. If
- not, see <https://www.gnu.org/licenses/>. */
-
-#include <stddef.h>
-#include <string.h>
-#include <signal.h>
-#include <stdint.h>
-
-#include <execinfo.h>
-#include <libc-vdso.h>
-
-/* This is the stack layout we see with every stack frame.
- Note that every routine is required by the ABI to lay out the stack
- like this.
-
- +----------------+ +-----------------+
- %r1 -> | %r1 last frame--------> | %r1 last frame--->... --> NULL
- | | | |
- | cr save | | cr save |
- | | | |
- | (unused) | | return address |
- +----------------+ +-----------------+
-*/
-struct layout
-{
- struct layout *next;
- long int condition_register;
- void *return_address;
-};
-
-/* Since the signal handler is just like any other function it needs to
- save/restore its LR and it will save it into callers stack frame.
- Since a signal handler doesn't have a caller, the kernel creates a
- dummy frame to make it look like it has a caller. */
-struct signal_frame_64 {
-#define SIGNAL_FRAMESIZE 128
- char dummy[SIGNAL_FRAMESIZE];
- ucontext_t uc;
- /* We don't care about the rest, since the IP value is at 'uc' field. */
-};
-
-/* Test if the address match to the inside the trampoline code.
- Up to and including kernel 5.8, returning from an interrupt or syscall to a
- signal handler starts execution directly at the handler's entry point, with
- LR set to address of the sigreturn trampoline (the vDSO symbol).
- Newer kernels will branch to signal handler from the trampoline instead, so
- checking the stacktrace against the vDSO entrypoint does not work in such
- case.
- The vDSO branches with a 'bctrl' instruction, so checking either the
- vDSO address itself and the next instruction should cover all kernel
- versions. */
-static inline bool
-is_sigtramp_address (void *nip)
-{
-#ifdef HAVE_SIGTRAMP_RT64
- if (nip == GLRO (dl_vdso_sigtramp_rt64) ||
- nip == GLRO (dl_vdso_sigtramp_rt64) + 4)
- return true;
-#endif
- return false;
-}
-
-int
-__backtrace (void **array, int size)
-{
- struct layout *current;
- int count;
-
- /* Force gcc to spill LR. */
- asm volatile ("" : "=l"(current));
-
- /* Get the address on top-of-stack. */
- asm volatile ("ld %0,0(1)" : "=r"(current));
-
- for ( count = 0;
- current != NULL && count < size;
- current = current->next, count++)
- {
- array[count] = current->return_address;
-
- /* Check if the symbol is the signal trampoline and get the interrupted
- * symbol address from the trampoline saved area. */
- if (is_sigtramp_address (current->return_address))
- {
- struct signal_frame_64 *sigframe = (struct signal_frame_64*) current;
- if (count + 1 == size)
- break;
- array[++count] = (void*) sigframe->uc.uc_mcontext.gp_regs[PT_NIP];
- current = (void*) sigframe->uc.uc_mcontext.gp_regs[PT_R1];
- }
- }
-
- /* It's possible the second-last stack frame can't return
- (that is, it's __libc_start_main), in which case
- the CRT startup code will have set its LR to 'NULL'. */
- if (count > 0 && array[count-1] == NULL)
- count--;
-
- return count;
-}
-weak_alias (__backtrace, backtrace)
-libc_hidden_def (__backtrace)
# ifdef HAVE_GET_TBFREQ
PROCINFO_CLASS uint64_t (*_dl_vdso_get_tbfreq)(void) RELRO;
# endif
-/* The sigtramp are used on powerpc backtrace without using
- INLINE_VSYSCALL, so there is no need to set their type. */
-# ifdef HAVE_SIGTRAMP_RT64
-PROCINFO_CLASS void *_dl_vdso_sigtramp_rt64 RELRO;
-# endif
-# ifdef HAVE_SIGTRAMP_RT32
-PROCINFO_CLASS void *_dl_vdso_sigtramp_rt32 RELRO;
-# endif
-# ifdef HAVE_SIGTRAMP_32
-PROCINFO_CLASS void *_dl_vdso_sigtramp_32 RELRO;
-# endif
#endif
#undef RELRO
#ifdef HAVE_GET_TBFREQ
GLRO(dl_vdso_get_tbfreq) = dl_vdso_vsym (HAVE_GET_TBFREQ);
#endif
-#ifdef HAVE_SIGTRAMP_RT64
- GLRO(dl_vdso_sigtramp_rt64) = dl_vdso_vsym (HAVE_SIGTRAMP_RT64);
-#endif
-#ifdef HAVE_SIGTRAMP_RT32
- GLRO(dl_vdso_sigtramp_rt32) = dl_vdso_vsym (HAVE_SIGTRAMP_RT32);
-#endif
-#ifdef HAVE_SIGTRAMP_32
- GLRO(dl_vdso_sigtramp_32) = dl_vdso_vsym (HAVE_SIGTRAMP_32);
-#endif
}
#endif
#define HAVE_GETTIMEOFDAY_VSYSCALL "__kernel_gettimeofday"
#define HAVE_GET_TBFREQ "__kernel_get_tbfreq"
-#if defined(__PPC64__) || defined(__powerpc64__)
-# define HAVE_SIGTRAMP_RT64 "__kernel_sigtramp_rt64"
-#else
-# define HAVE_SIGTRAMP_32 "__kernel_sigtramp32"
-# define HAVE_SIGTRAMP_RT32 "__kernel_sigtramp_rt32"
-#endif
-
#endif /* _LINUX_POWERPC_SYSDEP_H */
projects / thirdparty / glibc.git / commitdiff
