diff --git a/drivers/s390/crypto/ap_asm.h b/drivers/s390/crypto/ap_asm.h
index 7a630047c372..287b4ad0999e 100644
--- a/drivers/s390/crypto/ap_asm.h
+++ b/drivers/s390/crypto/ap_asm.h
@@ -129,7 +129,6 @@ static inline struct ap_queue_status ap_nqap(ap_qid_t qid,
 					     unsigned long long psmid,
 					     void *msg, size_t length)
 {
-	struct msgblock { char _[length]; };
 	register unsigned long reg0 asm ("0") = qid | 0x40000000UL;
 	register struct ap_queue_status reg1 asm ("1");
 	register unsigned long reg2 asm ("2") = (unsigned long) msg;
@@ -141,8 +140,8 @@ static inline struct ap_queue_status ap_nqap(ap_qid_t qid,
 		"0: .long 0xb2ad0042\n"		/* NQAP */
 		"   brc   2,0b"
 		: "+d" (reg0), "=d" (reg1), "+d" (reg2), "+d" (reg3)
-		: "d" (reg4), "d" (reg5), "m" (*(struct msgblock *) msg)
-		: "cc");
+		: "d" (reg4), "d" (reg5)
+		: "cc", "memory");
 	return reg1;
 }
 
@@ -168,7 +167,6 @@ static inline struct ap_queue_status ap_dqap(ap_qid_t qid,
 					     unsigned long long *psmid,
 					     void *msg, size_t length)
 {
-	struct msgblock { char _[length]; };
 	register unsigned long reg0 asm("0") = qid | 0x80000000UL;
 	register struct ap_queue_status reg1 asm ("1");
 	register unsigned long reg2 asm("2") = 0UL;
@@ -182,8 +180,8 @@ static inline struct ap_queue_status ap_dqap(ap_qid_t qid,
 		"0: .long 0xb2ae0064\n"		/* DQAP */
 		"   brc   6,0b\n"
 		: "+d" (reg0), "=d" (reg1), "+d" (reg2),
-		"+d" (reg4), "+d" (reg5), "+d" (reg6), "+d" (reg7),
-		"=m" (*(struct msgblock *) msg) : : "cc");
+		  "+d" (reg4), "+d" (reg5), "+d" (reg6), "+d" (reg7)
+		: : "cc", "memory");
 	*psmid = (((unsigned long long) reg6) << 32) + reg7;
 	return reg1;
 }