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| author | Dave Airlie <airlied@redhat.com> | 2023-08-24 00:26:06 +0300 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2023-08-24 00:26:06 +0300 |
| commit | fdebffeba8b877368ddcc139c26278c1c97931a4 (patch) | |
| tree | 5ebf85a3e26d55ea388aa7a8608222205a4d59ba /tools/testing/selftests/rseq/rseq.c | |
| parent | cacaeb27ade4b793c456179bb6eda4592d206cd8 (diff) | |
| parent | 706a741595047797872e669b3101429ab8d378ef (diff) | |
| download | linux-fdebffeba8b877368ddcc139c26278c1c97931a4.tar.xz | |
BackMerge tag 'v6.5-rc7' into drm-next
Linux 6.5-rc7
This is needed for the CI stuff and the msm pull has fixes in it.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'tools/testing/selftests/rseq/rseq.c')
| -rw-r--r-- | tools/testing/selftests/rseq/rseq.c | 30 |
1 files changed, 24 insertions, 6 deletions
diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c index 4e4aa006004c..96e812bdf8a4 100644 --- a/tools/testing/selftests/rseq/rseq.c +++ b/tools/testing/selftests/rseq/rseq.c @@ -31,12 +31,22 @@ #include <sys/auxv.h> #include <linux/auxvec.h> +#include <linux/compiler.h> + #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 +165,17 @@ 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 */ |