From 7b8fc26c40d6cf4c6751a045c9e42bbb7e78d81b Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Mon, 31 Aug 2026 14:22:48 -0700 Subject: [PATCH] xor: add missing vzeroupper to AVX code Since the AVX optimized XOR code uses YMM registers, execute vzeroupper before returning from it. This is needed to avoid degrading the performance of any later SSE code that may happen to be executed. Link: https://lore.kernel.org/20260831212248.213805-1-ebiggers@kernel.org Fixes: ea4d26ae24e5 ("raid5: add AVX optimized RAID5 checksumming") Signed-off-by: Eric Biggers Signed-off-by: Andrew Morton Cc: Christoph Hellwig Cc: --- lib/raid/xor/x86/xor-avx.c | 1 + 1 file changed, 1 insertion(+) diff --git a/lib/raid/xor/x86/xor-avx.c b/lib/raid/xor/x86/xor-avx.c index f7777d7aa269..95b21e7225e8 100644 --- a/lib/raid/xor/x86/xor-avx.c +++ b/lib/raid/xor/x86/xor-avx.c @@ -147,6 +147,7 @@ static void xor_gen_avx(void *dest, void **srcs, unsigned int src_cnt, { kernel_fpu_begin(); xor_gen_avx_inner(dest, srcs, src_cnt, bytes); + asm volatile("vzeroupper"); kernel_fpu_end(); }