From a16e8dbc043720abcb37fc7dca313e720b4e0f0c Mon Sep 17 00:00:00 2001
From: "Moger, Babu" <Babu.Moger@amd.com>
Date: Thu, 7 Nov 2019 18:00:57 +0000
Subject: [PATCH] i386: Add missing cpu feature bits in EPYC model
Adds the following missing CPUID bits:
perfctr-core : core performance counter extensions support. Enables the VM
to use extended performance counter support. It enables six
programmable counters instead of 4 counters.
clzero : instruction zeroes out the 64 byte cache line specified in RAX.
xsaveerptr : XSAVE, XSAVE, FXSAVEOPT, XSAVEC, XSAVES always save error
pointers and FXRSTOR, XRSTOR, XRSTORS always restore error
pointers.
ibpb : Indirect Branch Prediction Barrie.
xsaves : XSAVES, XRSTORS and IA32_XSS supported.
Depends on following kernel commits:
40bc47b08b6e ("kvm: x86: Enumerate support for CLZERO instruction")
504ce1954fba ("KVM: x86: Expose XSAVEERPTR to the guest")
52297436199d ("kvm: svm: Update svm_xsaves_supported")
These new features will be added in EPYC-v3. The -cpu help output after the change.
x86 EPYC-v1 AMD EPYC Processor
x86 EPYC-v2 AMD EPYC Processor (with IBPB)
x86 EPYC-v3 AMD EPYC Processor
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <157314965662.23828.3063243729449408327.stgit@naples-babu.amd.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
target/i386/cpu.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index dc784941673..54f42dcd25b 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -3942,10 +3942,6 @@ static X86CPUDefinition builtin_x86_defs[] = {
CPUID_7_0_EBX_SMEP | CPUID_7_0_EBX_BMI2 | CPUID_7_0_EBX_RDSEED |
CPUID_7_0_EBX_ADX | CPUID_7_0_EBX_SMAP | CPUID_7_0_EBX_CLFLUSHOPT |
CPUID_7_0_EBX_SHA_NI,
- /* Missing: XSAVES (not supported by some Linux versions,
- * including v4.1 to v4.12).
- * KVM doesn't yet expose any XSAVES state save component.
- */
.features[FEAT_XSAVE] =
CPUID_XSAVE_XSAVEOPT | CPUID_XSAVE_XSAVEC |
CPUID_XSAVE_XGETBV1,
@@ -3968,6 +3964,19 @@ static X86CPUDefinition builtin_x86_defs[] = {
{ /* end of list */ }
}
},
+ {
+ .version = 3,
+ .props = (PropValue[]) {
+ { "ibpb", "on" },
+ { "perfctr-core", "on" },
+ { "clzero", "on" },
+ { "xsaveerptr", "on" },
+ { "xsaves", "on" },
+ { "model-id",
+ "AMD EPYC Processor" },
+ { /* end of list */ }
+ }
+ },
{ /* end of list */ }
}
},
--
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