KVM: x86: document KVM_REQ_PENDING_TIMER usage

Document that KVM_REQ_PENDING_TIMER is implicitly used during guest
entry.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/arch/x86/kvm/timer.c b/arch/x86/kvm/timer.c
index eea40439066c..4ddadb1a5ffe 100644
--- a/arch/x86/kvm/timer.c
+++ b/arch/x86/kvm/timer.c
@@ -12,7 +12,8 @@ static int __kvm_timer_fn(struct kvm_vcpu *vcpu, struct kvm_timer *ktimer)
         /*
          * There is a race window between reading and incrementing, but we do
          * not care about potentially loosing timer events in the !reinject
-         * case anyway.
+         * case anyway. Note: KVM_REQ_PENDING_TIMER is implicitly checked
+         * in vcpu_enter_guest.
          */
         if (ktimer->reinject || !atomic_read(&ktimer->pending)) {
                 atomic_inc(&ktimer->pending);