linux-kernel - [PATCH] x86/cpuid: expose AVX512_4VNNIW and AVX512

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Date:   Fri, 28 Oct 2016 17:12:40 +0800
From:   He Chen <he.chen@...ux.intel.com>
To:     kvm@...r.kernel.org
Cc:     linux-kernel@...r.kernel.org, x86@...nel.org,
        Paolo Bonzini <pbonzini@...hat.com>,
        Radim Krčmář <rkrcmar@...hat.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H . Peter Anvin" <hpa@...or.com>,
        Luwei Kang <luwei.kang@...el.com>,
        Piotr Luc <Piotr.Luc@...el.com>
Subject: [PATCH] x86/cpuid: expose AVX512_4VNNIW and AVX512_4FMAPS features to kvm guest

The spec can be found in Intel Software Developer Manual or in
Instruction Set Extensions Programming Reference.

Signed-off-by: Luwei Kang <luwei.kang@...el.com>
Signed-off-by: He Chen <he.chen@...ux.intel.com>
---
 arch/x86/kvm/cpuid.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index afa7bbb..328b169 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -376,6 +376,10 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 	/* cpuid 7.0.ecx*/
 	const u32 kvm_cpuid_7_0_ecx_x86_features = F(PKU) | 0 /*OSPKE*/;
 
+	/* cpuid 7.0.edx*/
+	const u32 kvm_cpuid_7_0_edx_x86_features =
+        0x4 /* AVX512-4VNNIW */ | 0x8 /* AVX512-4FMAPS */;
+
 	/* all calls to cpuid_count() should be made on the same cpu */
 	get_cpu();
 
@@ -458,12 +462,13 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 			/* PKU is not yet implemented for shadow paging. */
 			if (!tdp_enabled)
 				entry->ecx &= ~F(PKU);
+            entry->edx &= kvm_cpuid_7_0_edx_x86_features;
 		} else {
 			entry->ebx = 0;
 			entry->ecx = 0;
+            entry->edx = 0;
 		}
 		entry->eax = 0;
-		entry->edx = 0;
 		break;
 	}
 	case 9:
-- 
2.7.4