s390/nmi: fix order of register validation

When validating register contents first validate control registers
since these control the availability of features later being
validated.
For example the control register 0 should be validated first, before
the additional floating point (AFP) registers are validated, since
control register 0 contains the AFP-register control bit.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 12 insertions, 12 deletions

diff --git a/arch/s390/kernel/nmi.c b/arch/s390/kernel/nmi.c
index 56e14d073167..b76b5fef251e 100644
--- a/arch/s390/kernel/nmi.c
+++ b/arch/s390/kernel/nmi.c
@@ -116,6 +116,18 @@ static int notrace s390_validate_registers(union mci mci, int umode)
                         s390_handle_damage();
                 kill_task = 1;
         }
+        /* Validate control registers */
+        if (!mci.cr) {
+                /*
+                 * Control registers have unknown contents.
+                 * Can't recover and therefore stopping machine.
+                 */
+                s390_handle_damage();
+        } else {
+                asm volatile(
+                        "       lctlg   0,15,0(%0)"
+                        : : "a" (&S390_lowcore.cregs_save_area) : "memory");
+        }
         if (!mci.fp) {
                 /*
                  * Floating point registers can't be restored. If the
@@ -208,18 +220,6 @@ static int notrace s390_validate_registers(union mci mci, int umode)
                  */
                 kill_task = 1;
         }
-        /* Validate control registers */
-        if (!mci.cr) {
-                /*
-                 * Control registers have unknown contents.
-                 * Can't recover and therefore stopping machine.
-                 */
-                s390_handle_damage();
-        } else {
-                asm volatile(
-                        "       lctlg   0,15,0(%0)"
-                        : : "a" (&S390_lowcore.cregs_save_area) : "memory");
-        }
         /*
          * We don't even try to validate the TOD register, since we simply
          * can't write something sensible into that register.