KVM: x86: handle 0 write to TSC_DEADLINE MSR

0 should disable the timer, but start_hv_timer will recognize it as an expired timer instead. Signed-off-by: Radim Krčmář <[email protected]> Reviewed-by: Wanpeng Li <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
thoughtpolice · Oct 12, 2017 · 86bbc1e · 86bbc1e
1 parent 46bea48
commit 86bbc1e
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
@@ -1549,6 +1549,9 @@ static bool start_hv_timer(struct kvm_lapic *apic)
 	if (!apic_lvtt_period(apic) && atomic_read(&ktimer->pending))
 		return false;
 
+	if (!ktimer->tscdeadline)
+		return false;
+
 	r = kvm_x86_ops->set_hv_timer(apic->vcpu, ktimer->tscdeadline);
 	if (r < 0)
 		return false;