On Tue, Jan 05, 2021 at 12:47:23PM +0100, Paolo Bonzini wrote: > On 05/01/21 01:49, Yang Zhong wrote: > > From: Kyung Min Park <kyung.min.park@xxxxxxxxx> > > > > Add AVX version of the Vector Neural Network (VNNI) Instructions. > > > > A processor supports AVX VNNI instructions if CPUID.0x07.0x1:EAX[4] is > > present. The following instructions are available when this feature is > > present. > > 1. VPDPBUS: Multiply and Add Unsigned and Signed Bytes > > 2. VPDPBUSDS: Multiply and Add Unsigned and Signed Bytes with Saturation > > 3. VPDPWSSD: Multiply and Add Signed Word Integers > > 4. VPDPWSSDS: Multiply and Add Signed Integers with Saturation > > > > The only in-kernel usage of this is kvm passthrough. The CPU feature > > flag is shown as "avx_vnni" in /proc/cpuinfo. > > > > This instruction is currently documented in the latest "extensions" > > manual (ISE). It will appear in the "main" manual (SDM) in the future. > > > > Signed-off-by: Kyung Min Park <kyung.min.park@xxxxxxxxx> > > Signed-off-by: Yang Zhong <yang.zhong@xxxxxxxxx> > > Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx> > > --- > > arch/x86/include/asm/cpufeatures.h | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h > > index f5ef2d5b9231..d10d9962bd9b 100644 > > --- a/arch/x86/include/asm/cpufeatures.h > > +++ b/arch/x86/include/asm/cpufeatures.h > > @@ -293,6 +293,7 @@ > > #define X86_FEATURE_PER_THREAD_MBA (11*32+ 7) /* "" Per-thread Memory Bandwidth Allocation */ > > /* Intel-defined CPU features, CPUID level 0x00000007:1 (EAX), word 12 */ > > +#define X86_FEATURE_AVX_VNNI (12*32+ 4) /* AVX VNNI instructions */ > > #define X86_FEATURE_AVX512_BF16 (12*32+ 5) /* AVX512 BFLOAT16 instructions */ > > /* AMD-defined CPU features, CPUID level 0x80000008 (EBX), word 13 */ > > > > Boris, is it possible to have a topic branch for this patch? Just take it through your tree pls. Acked-by: Borislav Petkov <bp@xxxxxxx> Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette