diff options
Diffstat (limited to 'sysdeps/powerpc/powerpc64/backtrace.c')
| -rw-r--r-- | sysdeps/powerpc/powerpc64/backtrace.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/sysdeps/powerpc/powerpc64/backtrace.c b/sysdeps/powerpc/powerpc64/backtrace.c index ae64c5d7a5..37de9b5bdd 100644 --- a/sysdeps/powerpc/powerpc64/backtrace.c +++ b/sysdeps/powerpc/powerpc64/backtrace.c @@ -54,11 +54,22 @@ struct signal_frame_64 { /* 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)) + if (nip == GLRO (dl_vdso_sigtramp_rt64) || + nip == GLRO (dl_vdso_sigtramp_rt64) + 4) return true; #endif return false; |