x86/cpufeatures: Fix dependencies for GFNI, VAES, and VPCLMULQDQ

Fix cpuid_deps[] to list the correct dependencies for GFNI, VAES, and
VPCLMULQDQ.  These features don't depend on AVX512, and there exist CPUs
that support these features but not AVX512.  GFNI actually doesn't even
depend on AVX.

This prevents GFNI from being unnecessarily disabled if AVX is disabled
to mitigate the GDS vulnerability.

This also prevents all three features from being unnecessarily disabled
if AVX512VL (or its dependency AVX512F) were to be disabled, but it
looks like there isn't any case where this happens anyway.

Fixes: c128dbfa0f87 ("x86/cpufeatures: Enable new SSE/AVX/AVX512 CPU features")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20240417060434.47101-1-ebiggers@kernel.org

diff --git a/arch/x86/kernel/cpu/cpuid-deps.c b/arch/x86/kernel/cpu/cpuid-deps.c
index b7174209d855c634a701aaf489372b087f464006..946813d816bfc2948eccc823300db283f99f91d4 100644 (file)
--- a/arch/x86/kernel/cpu/cpuid-deps.c
+++ b/arch/x86/kernel/cpu/cpuid-deps.c
@@ -44,7 +44,10 @@ static const struct cpuid_dep cpuid_deps[] = {
        { X86_FEATURE_F16C,                     X86_FEATURE_XMM2,     },
        { X86_FEATURE_AES,                      X86_FEATURE_XMM2      },
        { X86_FEATURE_SHA_NI,                   X86_FEATURE_XMM2      },
+       { X86_FEATURE_GFNI,                     X86_FEATURE_XMM2      },
        { X86_FEATURE_FMA,                      X86_FEATURE_AVX       },
+       { X86_FEATURE_VAES,                     X86_FEATURE_AVX       },
+       { X86_FEATURE_VPCLMULQDQ,               X86_FEATURE_AVX       },
        { X86_FEATURE_AVX2,                     X86_FEATURE_AVX,      },
        { X86_FEATURE_AVX512F,                  X86_FEATURE_AVX,      },
        { X86_FEATURE_AVX512IFMA,               X86_FEATURE_AVX512F   },
@@ -56,9 +59,6 @@ static const struct cpuid_dep cpuid_deps[] = {
        { X86_FEATURE_AVX512VL,                 X86_FEATURE_AVX512F   },
        { X86_FEATURE_AVX512VBMI,               X86_FEATURE_AVX512F   },
        { X86_FEATURE_AVX512_VBMI2,             X86_FEATURE_AVX512VL  },
-       { X86_FEATURE_GFNI,                     X86_FEATURE_AVX512VL  },
-       { X86_FEATURE_VAES,                     X86_FEATURE_AVX512VL  },
-       { X86_FEATURE_VPCLMULQDQ,               X86_FEATURE_AVX512VL  },
        { X86_FEATURE_AVX512_VNNI,              X86_FEATURE_AVX512VL  },
        { X86_FEATURE_AVX512_BITALG,            X86_FEATURE_AVX512VL  },
        { X86_FEATURE_AVX512_4VNNIW,            X86_FEATURE_AVX512F   },