Commit 788fc1e9 authored Nov 09, 2018 by Jim Mattson Committed by Paolo Bonzini Dec 21, 2018

kvm: vmx: Allow guest read access to IA32_TSC



Let the guest read the IA32_TSC MSR with the generic RDMSR instruction
as well as the specific RDTSC(P) instructions. Note that the hardware
applies the TSC multiplier and offset (when applicable) to the result of
RDMSR(IA32_TSC), just as it does to the result of RDTSC(P).

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

parent 9ebdfe52

arch/x86/kvm/vmx/vmx.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -6401,6 +6401,7 @@ static struct kvm_vcpu vmx_create_vcpu(struct kvm kvm, unsigned int id)
		goto free_msrs;

		msr_bitmap = vmx->vmcs01.msr_bitmap;
		vmx_disable_intercept_for_msr(msr_bitmap, MSR_IA32_TSC, MSR_TYPE_R);
		vmx_disable_intercept_for_msr(msr_bitmap, MSR_FS_BASE, MSR_TYPE_RW);
		vmx_disable_intercept_for_msr(msr_bitmap, MSR_GS_BASE, MSR_TYPE_RW);
		vmx_disable_intercept_for_msr(msr_bitmap, MSR_KERNEL_GS_BASE, MSR_TYPE_RW);

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