diff options
| author | Takashi Iwai <tiwai@suse.de> | 2023-08-24 09:27:21 +0200 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2023-08-24 09:27:21 +0200 |
| commit | a057efde80453c68c60e156803578a654b52c39f (patch) | |
| tree | 51c312e95de536b6a29d18a12cfdba72029e09ad /tools/testing/selftests/rseq/rseq.c | |
| parent | 17a1eab7b70d85fc5711f37bb6e530b771736bb7 (diff) | |
| parent | a4a6eed851bb661477654d772807d0e5aee5629c (diff) | |
Merge branch 'for-linus' into for-next
Back-merge the 6.5-devel branch for the clean patch application for
6.6 and resolving merge conflicts.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'tools/testing/selftests/rseq/rseq.c')
| -rw-r--r-- | tools/testing/selftests/rseq/rseq.c | 28 |
1 files changed, 22 insertions, 6 deletions
diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c index 4e4aa006004c..a723da253244 100644 --- a/tools/testing/selftests/rseq/rseq.c +++ b/tools/testing/selftests/rseq/rseq.c @@ -34,9 +34,17 @@ #include "../kselftest.h" #include "rseq.h" -static const ptrdiff_t *libc_rseq_offset_p; -static const unsigned int *libc_rseq_size_p; -static const unsigned int *libc_rseq_flags_p; +/* + * Define weak versions to play nice with binaries that are statically linked + * against a libc that doesn't support registering its own rseq. + */ +__weak ptrdiff_t __rseq_offset; +__weak unsigned int __rseq_size; +__weak unsigned int __rseq_flags; + +static const ptrdiff_t *libc_rseq_offset_p = &__rseq_offset; +static const unsigned int *libc_rseq_size_p = &__rseq_size; +static const unsigned int *libc_rseq_flags_p = &__rseq_flags; /* Offset from the thread pointer to the rseq area. */ ptrdiff_t rseq_offset; @@ -155,9 +163,17 @@ unsigned int get_rseq_feature_size(void) static __attribute__((constructor)) void rseq_init(void) { - libc_rseq_offset_p = dlsym(RTLD_NEXT, "__rseq_offset"); - libc_rseq_size_p = dlsym(RTLD_NEXT, "__rseq_size"); - libc_rseq_flags_p = dlsym(RTLD_NEXT, "__rseq_flags"); + /* + * If the libc's registered rseq size isn't already valid, it may be + * because the binary is dynamically linked and not necessarily due to + * libc not having registered a restartable sequence. Try to find the + * symbols if that's the case. + */ + if (!*libc_rseq_size_p) { + libc_rseq_offset_p = dlsym(RTLD_NEXT, "__rseq_offset"); + libc_rseq_size_p = dlsym(RTLD_NEXT, "__rseq_size"); + libc_rseq_flags_p = dlsym(RTLD_NEXT, "__rseq_flags"); + } if (libc_rseq_size_p && libc_rseq_offset_p && libc_rseq_flags_p && *libc_rseq_size_p != 0) { /* rseq registration owned by glibc */ |