From 4c292a009700755a1e6b234063ef3f2db235aaae Mon Sep 17 00:00:00 2001
From: Dominik Dingel <dingel@linux.vnet.ibm.com>
Date: Tue, 11 Aug 2015 11:12:12 +0200
Subject: [PATCH] s390x/kvm: don't enable CMMA when hugetlbfs will be used

On hugetlbfs CMMA will not be useful as every ESSA instruction will trap.
So don't offer CMMA to guests with a hugepages backing.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
---
 target-s390x/kvm.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/target-s390x/kvm.c b/target-s390x/kvm.c
index c3be180de2..75a0e5d1c3 100644
--- a/target-s390x/kvm.c
+++ b/target-s390x/kvm.c
@@ -258,7 +258,9 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
     cap_mem_op = kvm_check_extension(s, KVM_CAP_S390_MEM_OP);
     cap_s390_irq = kvm_check_extension(s, KVM_CAP_S390_INJECT_IRQ);
 
-    kvm_s390_enable_cmma(s);
+    if (!mem_path) {
+        kvm_s390_enable_cmma(s);
+    }
 
     if (!kvm_check_extension(s, KVM_CAP_S390_GMAP)
         || !kvm_check_extension(s, KVM_CAP_S390_COW)) {