6.17-stable review patch. If anyone has any objections, please let me know.
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From: Peter Zijlstra peterz@infradead.org
commit 0d6e9ec80cebf9b378a1d3a01144e576d731c397 upstream.
Leyvi Rose reported that his X86_NATIVE_CPU=y build is failing because our instruction decoder doesn't support SSE4a and the AMDGPU code seems to be generating those with his compiler of choice (CLANG+LTO).
Now, our normal build flags disable SSE MMX SSE2 3DNOW AVX, but then CC_FLAGS_FPU re-enable SSE SSE2.
Since nothing mentions SSE3 or SSE4, I'm assuming that -msse (or its negative) control all SSE variants -- but why then explicitly enumerate SSE2 ?
Anyway, until the instruction decoder gets fixed, explicitly disallow SSE4a (an AMD specific SSE4 extension).
Fixes: ea1dcca1de12 ("x86/kbuild/64: Add the CONFIG_X86_NATIVE_CPU option to locally optimize the kernel with '-march=native'") Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Acked-by: Borislav Petkov (AMD) bp@alien8.de Acked-by: Arisu Tachibana arisu.tachibana@miraclelinux.com Acked-by: Christian König christian.koenig@amd.com Acked-by: Harry Wentland harry.wentland@amd.com Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -74,7 +74,7 @@ export BITS # # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383 # -KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow -mno-avx +KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow -mno-avx -mno-sse4a KBUILD_RUSTFLAGS += --target=$(objtree)/scripts/target.json KBUILD_RUSTFLAGS += -Ctarget-feature=-sse,-sse2,-sse3,-ssse3,-sse4.1,-sse4.2,-avx,-avx2