[PATCH 4.19 55/56] KVM: LAPIC: Prevent setting the tscdeadline timer if the lapic is hw disabled

From: Greg Kroah-Hartman
Date: Mon Aug 03 2020 - 08:33:41 EST


From: Wanpeng Li <wanpengli@xxxxxxxxxxx>

commit d2286ba7d574ba3103a421a2f9ec17cb5b0d87a1 upstream.

Prevent setting the tscdeadline timer if the lapic is hw disabled.

Fixes: bce87cce88 (KVM: x86: consolidate different ways to test for in-kernel LAPIC)
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
Message-Id: <1596165141-28874-1-git-send-email-wanpengli@xxxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/x86/kvm/lapic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2034,7 +2034,7 @@ void kvm_set_lapic_tscdeadline_msr(struc
{
struct kvm_lapic *apic = vcpu->arch.apic;

- if (!lapic_in_kernel(vcpu) || apic_lvtt_oneshot(apic) ||
+ if (!kvm_apic_present(vcpu) || apic_lvtt_oneshot(apic) ||
apic_lvtt_period(apic))
return;