[PATCH v2 3/8] crypto: x86 - Stop using cpu_has_xfeatures()
David Laight
david.laight.linux at gmail.com
Tue Jul 28 02:30:18 PDT 2026
On Mon, 27 Jul 2026 19:15:58 -0700
Eric Biggers <ebiggers at kernel.org> wrote:
> Checking both boot_cpu_has(X86_FEATURE_AVX*) and cpu_has_xfeatures() has
> never really been needed in practice, and it's never been universally
> done (e.g., lib/raid/ omits cpu_has_xfeatures()). Nevertheless, both
> x86 and UML now explicitly clear the AVX and AVX-512 flags if their
> xfeatures are missing, which should remove any remaining doubts.
>
> Thus, remove all the calls to cpu_has_xfeatures(), as well as the
> related checks of boot_cpu_has(X86_FEATURE_OSXSAVE).
>
> In a few cases there was no corresponding boot_cpu_has(X86_FEATURE_AVX*)
> check, so add the missing ones.
>
> Signed-off-by: Eric Biggers <ebiggers at kernel.org>
> ---
...
> --- a/arch/x86/crypto/aria_gfni_avx512_glue.c
> +++ b/arch/x86/crypto/aria_gfni_avx512_glue.c
> @@ -196,24 +196,15 @@ static struct skcipher_alg aria_algs[] = {
>
> static int __init aria_avx512_init(void)
> {
> - const char *feature_name;
> -
> if (!boot_cpu_has(X86_FEATURE_AVX) ||
> !boot_cpu_has(X86_FEATURE_AVX2) ||
Doesn't AVX2 require AVX support?
> !boot_cpu_has(X86_FEATURE_AVX512F) ||
> !boot_cpu_has(X86_FEATURE_AVX512VL) ||
And (less sure) AVX512xxx require AVX2?
So the extra checks could be reduced.
David
> - !boot_cpu_has(X86_FEATURE_GFNI) ||
> - !boot_cpu_has(X86_FEATURE_OSXSAVE)) {
> + !boot_cpu_has(X86_FEATURE_GFNI)) {
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