[Qemu-devel] [PATCH 1/1] s390x/ais: for 2.10 stable: disable ais facility

[Christian Borntraeger <borntraeger@de.ibm.com>]

The migration interface for ais was introduced with kernel 4.13
but the capability itself had been active since 4.12. As migration
support is considered necessary lets disable ais in the 2.10
stable version. A proper fix and re-enablement will be done
for qemu 2.11.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
---
 target/s390x/kvm.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c
index c4c5791..eb0dbb3 100644
--- a/target/s390x/kvm.c
+++ b/target/s390x/kvm.c
@@ -308,8 +308,13 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
         }
     }
 
-    /* Try to enable AIS facility */
-    kvm_vm_enable_cap(s, KVM_CAP_S390_AIS, 0);
+    /*
+     * The migration interface for ais was introduced with kernel 4.13
+     * but the capability itself had been active since 4.12. As migration
+     * support is considered necessary let's disable ais in the 2.10
+     * machine.
+     */
+    /* kvm_vm_enable_cap(s, KVM_CAP_S390_AIS, 0); */
 
     qemu_mutex_init(&qemu_sigp_mutex);
 
-- 
2.9.4