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i386: Add missing cpu feature bits in EPYC model

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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>
This commit is contained in:
Moger, Babu 2019-11-07 18:00:57 +00:00 committed by Eduardo Habkost
parent c63938df0a
commit a16e8dbc04
1 changed files with 13 additions and 4 deletions
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17
target/i386/cpu.c
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@ -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 */ }
}
},