[PATCH v4 4/5] KVM: LAPIC: Don't posted inject already-expired timer

Wanpeng Li
2019-06-17T11:25:20Z

From: Wanpeng Li <wanpengli@tencent.com>

already-expired timer interrupt can be injected to guest when vCPU who
arms the lapic timer re-vmentry, don't posted inject in this case.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
---
arch/x86/kvm/lapic.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 665b1bb..1a31389 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1452,7 +1452,7 @@ static void kvm_apic_inject_pending_timer_irqs(struct kvm_lapic *apic)
}
}

-static void apic_timer_expired(struct kvm_lapic *apic)
+static void apic_timer_expired(struct kvm_lapic *apic, bool can_pi_inject)
{
struct kvm_vcpu *vcpu = apic->vcpu;
struct swait_queue_head *q = &vcpu->wq;
@@ -1461,7 +1461,7 @@ static void apic_timer_expired(struct kvm_lapic *apic)
if (atomic_read(&apic->lapic_timer.pending))
return;

- if (posted_interrupt_inject_timer(apic->vcpu)) {
+ if (can_pi_inject && posted_interrupt_inject_timer(apic->vcpu)) {
kvm_apic_inject_pending_timer_irqs(apic);
return;
}
@@ -1605,7 +1605,7 @@ static void start_sw_tscdeadline(struct kvm_lapic *apic)
expire = ktime_sub_ns(expire, ktimer->timer_advance_ns);
hrtimer_start(&ktimer->timer, expire, HRTIMER_MODE_ABS);
} else
- apic_timer_expired(apic);
+ apic_timer_expired(apic, false);

local_irq_restore(flags);
}
@@ -1695,7 +1695,7 @@ static void start_sw_period(struct kvm_lapic *apic)

if (ktime_after(ktime_get(),
apic->lapic_timer.target_expiration)) {
- apic_timer_expired(apic);
+ apic_timer_expired(apic, false);

if (apic_lvtt_oneshot(apic))
return;
@@ -1757,7 +1757,7 @@ static bool start_hv_timer(struct kvm_lapic *apic)
if (atomic_read(&ktimer->pending)) {
cancel_hv_timer(apic);
} else if (expired) {
- apic_timer_expired(apic);
+ apic_timer_expired(apic, false);
cancel_hv_timer(apic);
}
}
@@ -1807,7 +1807,7 @@ void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu)
goto out;
WARN_ON(swait_active(&vcpu->wq));
cancel_hv_timer(apic);
- apic_timer_expired(apic);
+ apic_timer_expired(apic, false);

if (apic_lvtt_period(apic) && apic->lapic_timer.period) {
advance_periodic_target_expiration(apic);
@@ -2310,7 +2310,7 @@ static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
struct kvm_lapic *apic = container_of(ktimer, struct kvm_lapic, lapic_timer);

- apic_timer_expired(apic);
+ apic_timer_expired(apic, true);

if (lapic_is_periodic(apic)) {
advance_periodic_target_expiration(apic);
--
2.7.4