1 files changed, 27 insertions, 11 deletions

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 152591f9243a..17fa4ab1b834 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1410,6 +1410,9 @@ int kvm_lapic_reg_read(struct kvm_lapic *apic, u32 offset, int len,
 	if (!apic_x2apic_mode(apic))
 		valid_reg_mask |= APIC_REG_MASK(APIC_ARBPRI);
 
+	if (alignment + len > 4)
+		return 1;
+
 	if (offset > 0x3f0 || !(valid_reg_mask & APIC_REG_MASK(offset)))
 		return 1;
 
@@ -1494,6 +1497,15 @@ static void limit_periodic_timer_frequency(struct kvm_lapic *apic)
 
 static void cancel_hv_timer(struct kvm_lapic *apic);
 
+static void cancel_apic_timer(struct kvm_lapic *apic)
+{
+	hrtimer_cancel(&apic->lapic_timer.timer);
+	preempt_disable();
+	if (apic->lapic_timer.hv_timer_in_use)
+		cancel_hv_timer(apic);
+	preempt_enable();
+}
+
 static void apic_update_lvtt(struct kvm_lapic *apic)
 {
 	u32 timer_mode = kvm_lapic_get_reg(apic, APIC_LVTT) &
@@ -1502,11 +1514,7 @@ static void apic_update_lvtt(struct kvm_lapic *apic)
 	if (apic->lapic_timer.timer_mode != timer_mode) {
 		if (apic_lvtt_tscdeadline(apic) != (timer_mode ==
 				APIC_LVT_TIMER_TSCDEADLINE)) {
-			hrtimer_cancel(&apic->lapic_timer.timer);
-			preempt_disable();
-			if (apic->lapic_timer.hv_timer_in_use)
-				cancel_hv_timer(apic);
-			preempt_enable();
+			cancel_apic_timer(apic);
 			kvm_lapic_set_reg(apic, APIC_TMICT, 0);
 			apic->lapic_timer.period = 0;
 			apic->lapic_timer.tscdeadline = 0;
@@ -1598,11 +1606,19 @@ static void __kvm_wait_lapic_expire(struct kvm_vcpu *vcpu)
 	guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
 	apic->lapic_timer.advance_expire_delta = guest_tsc - tsc_deadline;
 
+	if (lapic_timer_advance_dynamic) {
+		adjust_lapic_timer_advance(vcpu, apic->lapic_timer.advance_expire_delta);
+		/*
+		 * If the timer fired early, reread the TSC to account for the
+		 * overhead of the above adjustment to avoid waiting longer
+		 * than is necessary.
+		 */
+		if (guest_tsc < tsc_deadline)
+			guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
+	}
+
 	if (guest_tsc < tsc_deadline)
 		__wait_lapic_expire(vcpu, tsc_deadline - guest_tsc);
-
-	if (lapic_timer_advance_dynamic)
-		adjust_lapic_timer_advance(vcpu, apic->lapic_timer.advance_expire_delta);
 }
 
 void kvm_wait_lapic_expire(struct kvm_vcpu *vcpu)
@@ -1661,7 +1677,7 @@ static void apic_timer_expired(struct kvm_lapic *apic, bool from_timer_fn)
 	}
 
 	atomic_inc(&apic->lapic_timer.pending);
-	kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu);
+	kvm_make_request(KVM_REQ_UNBLOCK, vcpu);
 	if (from_timer_fn)
 		kvm_vcpu_kick(vcpu);
 }
@@ -1913,8 +1929,8 @@ void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu)
 	if (!apic->lapic_timer.hv_timer_in_use)
 		goto out;
 	WARN_ON(rcuwait_active(&vcpu->wait));
-	cancel_hv_timer(apic);
 	apic_timer_expired(apic, false);
+	cancel_hv_timer(apic);
 
 	if (apic_lvtt_period(apic) && apic->lapic_timer.period) {
 		advance_periodic_target_expiration(apic);
@@ -2084,7 +2100,7 @@ int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
 		if (apic_lvtt_tscdeadline(apic))
 			break;
 
-		hrtimer_cancel(&apic->lapic_timer.timer);
+		cancel_apic_timer(apic);
 		kvm_lapic_set_reg(apic, APIC_TMICT, val);
 		start_apic_timer(apic);
 		break;