KVM: s390: a VCPU may only stop when no interrupts are left pending

As a SIGP STOP is an interrupt with the least priority, it may only result
in stop of the vcpu when no other interrupts are left pending.

To detect whether a non-stop irq is pending, we need a way to mask out
stop irqs from the general kvm_cpu_has_interrupt() function. For this
reason, the existing function (with an outdated name) is replaced by
kvm_s390_vcpu_has_irq() which allows to mask out pending stop irqs.

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index 08e01acc13c3..897669454fb0 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -74,6 +74,10 @@ static int handle_stop(struct kvm_vcpu *vcpu)
 
         vcpu->stat.exit_stop_request++;
 
+        /* delay the stop if any non-stop irq is pending */
+        if (kvm_s390_vcpu_has_irq(vcpu, 1))
+                return 0;
+
         /* avoid races with the injection/SIGP STOP code */
         spin_lock(&li->lock);
         flags = li->irq.stop.flags;