diff options
| author | Wanpeng Li | 2021-06-07 00:19:43 -0700 |
|---|---|---|
| committer | Paolo Bonzini | 2021-06-08 12:22:26 -0400 |
| commit | e898da784aed0ea65f7672d941c01dc9b79e6299 (patch) | |
| tree | 32206b1e1480ff8574a97ef8f569444858c117a4 | |
| parent | 4f13d471e5d11034d56161af56d0f9396bc0b384 (diff) | |
KVM: LAPIC: Write 0 to TMICT should also cancel vmx-preemption timer
According to the SDM 10.5.4.1:
A write of 0 to the initial-count register effectively stops the local
APIC timer, in both one-shot and periodic mode.
However, the lapic timer oneshot/periodic mode which is emulated by vmx-preemption
timer doesn't stop by writing 0 to TMICT since vmx->hv_deadline_tsc is still
programmed and the guest will receive the spurious timer interrupt later. This
patch fixes it by also cancelling the vmx-preemption timer when writing 0 to
the initial-count register.
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1623050385-100988-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/lapic.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 8120e8614b92..6d72d8f43310 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1494,6 +1494,15 @@ 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 +1511,7 @@ 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; @@ -2092,7 +2097,7 @@ 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; |