KVM: s390: Make psw available on all exits, not just a subset

This patch moves s390 processor status word into the base kvm_run
struct and keeps it up-to date on all userspace exits.

The userspace ABI is broken by this, however there are no applications
in the wild using this.  A capability check is provided so users can
verify the updated API exists.

Cc: stable@kernel.org
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/s390/include/asm/kvm.h b/arch/s390/include/asm/kvm.h
index 3dfcaeb..82b32a1 100644
--- a/arch/s390/include/asm/kvm.h
+++ b/arch/s390/include/asm/kvm.h
@@ -1,6 +1,5 @@
 #ifndef __LINUX_KVM_S390_H
 #define __LINUX_KVM_S390_H
-
 /*
  * asm-s390/kvm.h - KVM s390 specific structures and definitions
  *
@@ -15,6 +14,8 @@
  */
 #include <linux/types.h>
 
+#define __KVM_S390
+
 /* for KVM_GET_REGS and KVM_SET_REGS */
 struct kvm_regs {
 	/* general purpose regs for s390 */