aarch64: Fix the list of tested IFUNC variants [BZ #26818]

Some IFUNC variants are not compatible with BTI and MTE so don't
set them as usable for testing and benchmarking on a BTI or MTE
enabled system.

As far as IFUNC selectors are concerned a system is BTI enabled if
the cpu supports it and glibc was built with BTI branch protection.

Most IFUNC variants are BTI compatible, but thunderx2 memcpy and
memmove use a jump table with indirect jump, without a BTI j.

Fixes bug 26818.
This commit is contained in:
Szabolcs Nagy 2021-01-22 16:57:32 +00:00
parent ad47748992
commit 04c6a8073d
2 changed files with 6 additions and 4 deletions

View File

@ -40,13 +40,13 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
/* Support sysdeps/aarch64/multiarch/memcpy.c and memmove.c. */
IFUNC_IMPL (i, name, memcpy,
IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_thunderx)
IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_thunderx2)
IFUNC_IMPL_ADD (array, i, memcpy, !bti, __memcpy_thunderx2)
IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_falkor)
IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_simd)
IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_generic))
IFUNC_IMPL (i, name, memmove,
IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_thunderx)
IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_thunderx2)
IFUNC_IMPL_ADD (array, i, memmove, !bti, __memmove_thunderx2)
IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_falkor)
IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_simd)
IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_generic))
@ -58,11 +58,11 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
IFUNC_IMPL_ADD (array, i, memset, 1, __memset_kunpeng)
IFUNC_IMPL_ADD (array, i, memset, 1, __memset_generic))
IFUNC_IMPL (i, name, memchr,
IFUNC_IMPL_ADD (array, i, memchr, 1, __memchr_nosimd)
IFUNC_IMPL_ADD (array, i, memchr, !mte, __memchr_nosimd)
IFUNC_IMPL_ADD (array, i, memchr, 1, __memchr_generic))
IFUNC_IMPL (i, name, strlen,
IFUNC_IMPL_ADD (array, i, strlen, 1, __strlen_asimd)
IFUNC_IMPL_ADD (array, i, strlen, !mte, __strlen_asimd)
IFUNC_IMPL_ADD (array, i, strlen, 1, __strlen_mte))
return i;

View File

@ -30,5 +30,7 @@
GLRO(dl_aarch64_cpu_features).midr_el1; \
unsigned __attribute__((unused)) zva_size = \
GLRO(dl_aarch64_cpu_features).zva_size; \
bool __attribute__((unused)) bti = \
HAVE_AARCH64_BTI && GLRO(dl_aarch64_cpu_features).bti; \
bool __attribute__((unused)) mte = \
MTE_ENABLED ();