commit 66570e966dd9 ("kvm: x86: only provide PV features if enabled in
guest's CPUID") subtly changed the behavior of guest writes to
MSR_KVM_SYSTEM_TIME(_NEW). Restore the previous behavior; update the
masterclock any time the guest uses a different msr than before.
Fixes: 66570e966dd9 ("kvm: x86: only provide PV features if enabled in guest's CPUID")
Signed-off-by: Oliver Upton <oupton@xxxxxxxxxx>
Reviewed-by: Peter Shier <pshier@xxxxxxxxxx>
---
arch/x86/kvm/x86.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 2970045a885e..4f7dce1b1447 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1965,7 +1965,7 @@ static void kvm_write_system_time(struct kvm_vcpu *vcpu, gpa_t system_time,
struct kvm_arch *ka = &vcpu->kvm->arch;
if (vcpu->vcpu_id == 0 && !host_initiated) {
- if (ka->boot_vcpu_runs_old_kvmclock && old_msr)
+ if (ka->boot_vcpu_runs_old_kvmclock != old_msr)
kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
ka->boot_vcpu_runs_old_kvmclock = old_msr;
--
2.29.0.rc2.309.g374f81d7ae-goog
