From: David Hildenbrand <[email protected]> We sometimes get an underflow for the sleep duration, which most likely won't result in the short sleep time we wanted.
So let's check for sleep duration underflows and directly continue to run the guest if we get one. Acked-by: Christian Borntraeger <[email protected]> Acked-by: Cornelia Huck <[email protected]> Signed-off-by: David Hildenbrand <[email protected]> Signed-off-by: Christian Borntraeger <[email protected]> --- arch/s390/kvm/interrupt.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index a845e35..5744303 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -804,14 +804,20 @@ int kvm_s390_handle_wait(struct kvm_vcpu *vcpu) return -EOPNOTSUPP; /* disabled wait */ } - __set_cpu_idle(vcpu); if (!ckc_interrupts_enabled(vcpu)) { VCPU_EVENT(vcpu, 3, "%s", "enabled wait w/o timer"); + __set_cpu_idle(vcpu); goto no_timer; } now = get_tod_clock_fast() + vcpu->arch.sie_block->epoch; sltime = tod_to_ns(vcpu->arch.sie_block->ckc - now); + + /* underflow */ + if (vcpu->arch.sie_block->ckc < now) + return 0; + + __set_cpu_idle(vcpu); hrtimer_start(&vcpu->arch.ckc_timer, ktime_set (0, sltime) , HRTIMER_MODE_REL); VCPU_EVENT(vcpu, 5, "enabled wait via clock comparator: %llx ns", sltime); no_timer: -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
