s390/nmi: fix inline assembly constraints

Add missing memory clobbers / barriers or use the Q constraint where
possible to tell the compiler that the inline assemblies actually
access memory and not only pointers to memory.

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

diff --git a/arch/s390/kernel/nmi.c b/arch/s390/kernel/nmi.c
index 9a32f7419d783f6c7c0977690ddb304fbe83c878..9862196b4b891b5fc393d0d31cc2abb354a5ce95 100644 (file)
--- a/arch/s390/kernel/nmi.c
+++ b/arch/s390/kernel/nmi.c
@@ -102,7 +102,7 @@ static int notrace s390_validate_registers(union mci mci, int umode)
 {
        int kill_task;
        u64 zero;
-       void *fpt_save_area, *fpt_creg_save_area;
+       void *fpt_save_area;
 
        kill_task = 0;
        zero = 0;
@@ -130,7 +130,6 @@ static int notrace s390_validate_registers(union mci mci, int umode)
                        kill_task = 1;
        }
        fpt_save_area = &S390_lowcore.floating_pt_save_area;
-       fpt_creg_save_area = &S390_lowcore.fpt_creg_save_area;
        if (!mci.fc) {
                /*
                 * Floating point control register can't be restored.
@@ -142,11 +141,13 @@ static int notrace s390_validate_registers(union mci mci, int umode)
                 */
                if (S390_lowcore.fpu_flags & KERNEL_FPC)
                        s390_handle_damage();
-               asm volatile("lfpc 0(%0)" : : "a" (&zero), "m" (zero));
+               asm volatile("lfpc %0" : : "Q" (zero));
                if (!test_cpu_flag(CIF_FPU))
                        kill_task = 1;
-       } else
-               asm volatile("lfpc 0(%0)" : : "a" (fpt_creg_save_area));
+       } else {
+               asm volatile("lfpc %0"
+                            : : "Q" (S390_lowcore.fpt_creg_save_area));
+       }
 
        if (!MACHINE_HAS_VX) {
                /* Validate floating point registers */
@@ -167,7 +168,7 @@ static int notrace s390_validate_registers(union mci mci, int umode)
                        "       ld      13,104(%0)\n"
                        "       ld      14,112(%0)\n"
                        "       ld      15,120(%0)\n"
-                       : : "a" (fpt_save_area));
+                       : : "a" (fpt_save_area) : "memory");
        } else {
                /* Validate vector registers */
                union ctlreg0 cr0;
@@ -217,7 +218,7 @@ static int notrace s390_validate_registers(union mci mci, int umode)
        } else {
                asm volatile(
                        "       lctlg   0,15,0(%0)"
-                       : : "a" (&S390_lowcore.cregs_save_area));
+                       : : "a" (&S390_lowcore.cregs_save_area) : "memory");
        }
        /*
         * We don't even try to validate the TOD register, since we simply
@@ -234,9 +235,9 @@ static int notrace s390_validate_registers(union mci mci, int umode)
                        : : : "0", "cc");
        else
                asm volatile(
-                       "       l       0,0(%0)\n"
+                       "       l       0,%0\n"
                        "       sckpf"
-                       : : "a" (&S390_lowcore.tod_progreg_save_area)
+                       : : "Q" (S390_lowcore.tod_progreg_save_area)
                        : "0", "cc");
        /* Validate clock comparator register */
        set_clock_comparator(S390_lowcore.clock_comparator);