Re: [PATCH] x86/cpufeatures: Move the definition of X86_FEATURE_AMX_* to the word 18

From: Paolo Bonzini
Date: Tue Jan 18 2022 - 12:15:37 EST


On 1/18/22 18:11, Dave Hansen wrote:
What tree is this against? I see BF16 and INT8 in some old versions of
Chang's patches, but not current kernels. All I see right now in
tip/master is:

#define X86_FEATURE_AMX_TILE (18*32+24) /* AMX tile ...

It's still in the wrong spot, but the other two features aren't there.

It was added for the KVM side of AMX (commit 690a757d610e, "kvm: x86: Add CPUID support for Intel AMX") and is in Linus's tree.

Paolo


We have defined the word 18 for Intel-defined CPU features from CPUID level> 0x00000007:0 (EDX). Let's move the definitions of X86_FEATURE_AMX_* to
the> right entry to prevent misinterpretation. No functional change
intended.
Please, no "we's" in changelogs. Don't say, "let's move". Just say:
"Move..."

The subject could probably also be trimmed a bit. Perhaps:

x86/cpu: Move AMX CPU feature defines to correct word location