KVM: Ignore DEBUGCTL MSRs with no effect

Netware writes to DEBUGCTL and reads from the DEBUGCTL and LAST*IP MSRs
without further checks and is really confused to receive a #GP during that.
To make it happy we should just make them stubs, which is exactly what SVM
already does.

Writes to DEBUGCTL that are vendor-specific are resembled to behave as if the
virtual CPU does not know them.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This commit is contained in:
Alexander Graf 2008-07-22 08:00:45 +02:00 committed by Avi Kivity
parent 313dbd49dc
commit b5e2fec0eb

View File

@ -665,6 +665,18 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
pr_unimpl(vcpu, "%s: MSR_IA32_MCG_CTL 0x%llx, nop\n", pr_unimpl(vcpu, "%s: MSR_IA32_MCG_CTL 0x%llx, nop\n",
__func__, data); __func__, data);
break; break;
case MSR_IA32_DEBUGCTLMSR:
if (!data) {
/* We support the non-activated case already */
break;
} else if (data & ~(DEBUGCTLMSR_LBR | DEBUGCTLMSR_BTF)) {
/* Values other than LBR and BTF are vendor-specific,
thus reserved and should throw a #GP */
return 1;
}
pr_unimpl(vcpu, "%s: MSR_IA32_DEBUGCTLMSR 0x%llx, nop\n",
__func__, data);
break;
case MSR_IA32_UCODE_REV: case MSR_IA32_UCODE_REV:
case MSR_IA32_UCODE_WRITE: case MSR_IA32_UCODE_WRITE:
break; break;
@ -757,6 +769,11 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
case MSR_IA32_MC0_MISC+16: case MSR_IA32_MC0_MISC+16:
case MSR_IA32_UCODE_REV: case MSR_IA32_UCODE_REV:
case MSR_IA32_EBL_CR_POWERON: case MSR_IA32_EBL_CR_POWERON:
case MSR_IA32_DEBUGCTLMSR:
case MSR_IA32_LASTBRANCHFROMIP:
case MSR_IA32_LASTBRANCHTOIP:
case MSR_IA32_LASTINTFROMIP:
case MSR_IA32_LASTINTTOIP:
data = 0; data = 0;
break; break;
case MSR_MTRRcap: case MSR_MTRRcap: