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| author | Marcelo Tosatti <mtosatti@redhat.com> | 2008-06-06 16:37:36 -0300 |
|---|---|---|
| committer | Avi Kivity <avi@qumranet.com> | 2008-06-24 12:16:59 +0300 |
| commit | 06e05645661211b9eaadaf6344c335d2e80f0ba2 (patch) | |
| tree | 8846d2a5052aec44141e811c0a76fdb39c2e77ca /arch/x86/kvm/lapic.c | |
| parent | d4acf7e7abe45457e751525a2a4d5b693dfdd597 (diff) | |
| download | linux-06e05645661211b9eaadaf6344c335d2e80f0ba2.tar.gz linux-06e05645661211b9eaadaf6344c335d2e80f0ba2.tar.bz2 linux-06e05645661211b9eaadaf6344c335d2e80f0ba2.zip | |
KVM: close timer injection race window in __vcpu_run
If a timer fires after kvm_inject_pending_timer_irqs() but before
local_irq_disable() the code will enter guest mode and only inject such
timer interrupt the next time an unrelated event causes an exit.
It would be simpler if the timer->pending irq conversion could be done
with IRQ's disabled, so that the above problem cannot happen.
For now introduce a new vcpu requests bit to cancel guest entry.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Diffstat (limited to 'arch/x86/kvm/lapic.c')
| -rw-r--r-- | arch/x86/kvm/lapic.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index c297c50eba63..ebc03f5ae162 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -940,6 +940,7 @@ static int __apic_timer_fn(struct kvm_lapic *apic) wait_queue_head_t *q = &apic->vcpu->wq; atomic_inc(&apic->timer.pending); + set_bit(KVM_REQ_PENDING_TIMER, &apic->vcpu->requests); if (waitqueue_active(q)) { apic->vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE; wake_up_interruptible(q); |