[S390] clear_table inline assembly contraints

Tell the compile that the clear_table inline assembly writes to the
memory referenced by *s.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/arch/s390/include/asm/pgalloc.h b/arch/s390/include/asm/pgalloc.h
index f5b2bf3d7c1d..b2658b9220fe 100644
--- a/arch/s390/include/asm/pgalloc.h
+++ b/arch/s390/include/asm/pgalloc.h
@@ -28,6 +28,8 @@ void disable_noexec(struct mm_struct *, struct task_struct *);
 
 static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
 {
+        typedef struct { char _[n]; } addrtype;
+
         *s = val;
         n = (n / 256) - 1;
         asm volatile(
@@ -39,7 +41,8 @@ static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
                 "0:     mvc     256(256,%0),0(%0)\n"
                 "       la      %0,256(%0)\n"
                 "       brct    %1,0b\n"
-                : "+a" (s), "+d" (n));
+                : "+a" (s), "+d" (n), "=m" (*(addrtype *) s)
+                : "m" (*(addrtype *) s));
 }
 
 static inline void crst_table_init(unsigned long *crst, unsigned long entry)