KVM: s390: Fix kvm on IBM System z10

The z10 system supports large pages, kvm-s390 doesnt.
Make sure that we dont advertise large pages to avoid the guest crashing as
soon as the guest kernel activates DAT.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

arch/s390/kvm/priv.c

@@ -158,6 +158,7 @@ static int handle_stfl(struct kvm_vcpu *vcpu)
 
 	vcpu->stat.instruction_stfl++;
 	facility_list &= ~(1UL<<24); /* no stfle */
+	facility_list &= ~(1UL<<23); /* no large pages */
 
 	rc = copy_to_guest(vcpu, offsetof(struct _lowcore, stfl_fac_list),
 			   &facility_list, sizeof(facility_list));