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x86/fpu, crypto: Fix AVX2 feature tests

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For some CPU models I broke the AVX2 feature detection in:

  7bc371faa9 ("x86/fpu, crypto x86/camellia_aesni_avx2: Simplify the camellia_aesni_init() xfeature checks")
  534ff06e39 ("x86/fpu, crypto x86/serpent_avx2: Simplify the init() xfeature checks")

... because I did not realize that it's possible for a CPU to support
the xstate necessary for AVX2 execution (XSTATE_YMM), but not have
the AVX2 instructions themselves.

Restore the necessary CPUID checks as well.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ingo Molnar 2015-05-22 10:58:45 +02:00
parent 6f56a8d024
commit b54b4bbbf5
2 changed files with 9 additions and 0 deletions
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5
arch/x86/crypto/camellia_aesni_avx2_glue.c
View file

@ -562,6 +562,11 @@ static int __init camellia_aesni_init(void)
{
const char *feature_name;
if (!cpu_has_avx2 || !cpu_has_avx || !cpu_has_aes || !cpu_has_osxsave) {
pr_info("AVX2 or AES-NI instructions are not detected.\n");
return -ENODEV;
}
if (!cpu_has_xfeatures(XSTATE_SSE | XSTATE_YMM, &feature_name)) {
pr_info("CPU feature '%s' is not supported.\n", feature_name);
return -ENODEV;

4
arch/x86/crypto/serpent_avx2_glue.c
View file

@ -538,6 +538,10 @@ static int __init init(void)
{
const char *feature_name;
if (!cpu_has_avx2 || !cpu_has_osxsave) {
pr_info("AVX2 instructions are not detected.\n");
return -ENODEV;
}
if (!cpu_has_xfeatures(XSTATE_SSE | XSTATE_YMM, &feature_name)) {
pr_info("CPU feature '%s' is not supported.\n", feature_name);
return -ENODEV;