KVM: s390: do store status after handling STOP_ON_STOP bit

In handle_stop() handle the stop bit before doing the store status as
described for "Stop and Store Status" in the Principles of Operation.
We have to give up the local_int.lock before calling kvm store status
since it calls gmap_fault() which might sleep. Since local_int.lock
only protects local_int.* and not guest memory we can give up the lock.

Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 12 insertions, 8 deletions

diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index 776ef83c2771..361456577c6f 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -133,13 +133,6 @@ static int handle_stop(struct kvm_vcpu *vcpu)
 
         vcpu->stat.exit_stop_request++;
         spin_lock_bh(&vcpu->arch.local_int.lock);
-        if (vcpu->arch.local_int.action_bits & ACTION_STORE_ON_STOP) {
-                vcpu->arch.local_int.action_bits &= ~ACTION_STORE_ON_STOP;
-                rc = kvm_s390_vcpu_store_status(vcpu,
-                                                  KVM_S390_STORE_STATUS_NOADDR);
-                if (rc >= 0)
-                        rc = -EOPNOTSUPP;
-        }
 
         if (vcpu->arch.local_int.action_bits & ACTION_RELOADVCPU_ON_STOP) {
                 vcpu->arch.local_int.action_bits &= ~ACTION_RELOADVCPU_ON_STOP;
@@ -155,7 +148,18 @@ static int handle_stop(struct kvm_vcpu *vcpu)
                 rc = -EOPNOTSUPP;
         }
 
-        spin_unlock_bh(&vcpu->arch.local_int.lock);
+        if (vcpu->arch.local_int.action_bits & ACTION_STORE_ON_STOP) {
+                vcpu->arch.local_int.action_bits &= ~ACTION_STORE_ON_STOP;
+                /* store status must be called unlocked. Since local_int.lock
+                 * only protects local_int.* and not guest memory we can give
+                 * up the lock here */
+                spin_unlock_bh(&vcpu->arch.local_int.lock);
+                rc = kvm_s390_vcpu_store_status(vcpu,
+                                                KVM_S390_STORE_STATUS_NOADDR);
+                if (rc >= 0)
+                        rc = -EOPNOTSUPP;
+        } else
+                spin_unlock_bh(&vcpu->arch.local_int.lock);
         return rc;
 }