KVM: VMX: Fake emulate Intel perfctr MSRs (efa67e0d) · Commits · 戴 / test

Older linux guests (in this case, 2.6.9) can attempt to access the performance counter MSRs without a fixup section, and injecting a GPF kills the guest. Work around by allowing the guest to write those MSRs. Tested by me on RHEL-4 i386 and x86_64 guests, as well as F-9 guests. Signed-off-by:

Chris Lalancette <clalance@redhat.com> Signed-off-by:

Avi Kivity <avi@qumranet.com>

arch/x86/kvm/vmx.c

+12 −0

Original line number	Diff line number	Diff line
		@@ -920,6 +920,18 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
		break;
		case MSR_IA32_TIME_STAMP_COUNTER:
		guest_write_tsc(data);
		break;
		case MSR_P6_PERFCTR0:
		case MSR_P6_PERFCTR1:
		case MSR_P6_EVNTSEL0:
		case MSR_P6_EVNTSEL1:
		/*
		* Just discard all writes to the performance counters; this
		* should keep both older linux and windows 64-bit guests
		* happy
		*/
		pr_unimpl(vcpu, "unimplemented perfctr wrmsr: 0x%x data 0x%llx\n", msr_index, data);

		break;
		default:
		vmx_load_host_state(vmx);

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