diff --git a/src/arch/s390x/core/facility.c b/src/arch/s390x/core/facility.c
index d3ab6b453..0d169e733 100644
--- a/src/arch/s390x/core/facility.c
+++ b/src/arch/s390x/core/facility.c
@@ -46,7 +46,7 @@ int facility_is_installed ( unsigned int facility ) {
 	memset ( &facilities, 0, sizeof ( facilities ) );
 	max = ( ( sizeof ( facilities.mask ) /
 		  sizeof ( facilities.mask[0] ) ) - 1 );
-	__asm__ ( "stfle %0" : "=R" ( facilities ), "+r" ( max ) );
+	__asm__ ( "stfle %0" : "=R" ( facilities ), "+r" ( max ) : : "cc" );
 	DBGC ( &facilities, "FACILITY %016llx:%016llx:%016llx:%016llx\n",
 	       facilities.mask[0], facilities.mask[1], facilities.mask[2],
 	       facilities.mask[3] );
diff --git a/src/arch/s390x/core/prno.c b/src/arch/s390x/core/prno.c
index 75e6b7ca5..79b81c196 100644
--- a/src/arch/s390x/core/prno.c
+++ b/src/arch/s390x/core/prno.c
@@ -69,7 +69,8 @@ static int prno_entropy_enable ( void ) {
 		    "=a" ( dummy2 ),
 		    "=m" ( params )
 		  : "0" ( PRNO_FN_QUERY ),
-		    "1" ( &params ) );
+		    "1" ( &params )
+		  : "cc" );
 	if ( ! prno_is_supported ( &params.supported, PRNO_FN_TRNG ) ) {
 		DBGC ( colour, "PRNO does not support TRNG (%016llx:%016llx)\n",
 		       params.supported.mask[0], params.supported.mask[1] );
@@ -111,7 +112,8 @@ static int prno_get_noise ( noise_sample_t *noise ) {
 		    "+a" ( raw ),
 		    "+a" ( conditioned ),
 		    "=m" ( *noise )
-		  : "0" ( PRNO_FN_TRNG ) );
+		  : "0" ( PRNO_FN_TRNG )
+		  : "cc" );
 
 	return 0;
 }
diff --git a/src/arch/s390x/include/bits/bigint.h b/src/arch/s390x/include/bits/bigint.h
index 57d64832f..db8356e70 100644
--- a/src/arch/s390x/include/bits/bigint.h
+++ b/src/arch/s390x/include/bits/bigint.h
@@ -46,7 +46,8 @@ bigint_add_raw ( const unsigned long *addend0, unsigned long *value0,
 		    "=&r" ( index_carry ),
 		    "+S" ( *value )
 		  : "S" ( *addend ),
-		    "2" ( size ) );
+		    "2" ( size )
+		  : "cc" );
 
 	return index_carry;
 }
@@ -86,7 +87,8 @@ bigint_subtract_raw ( const unsigned long *subtrahend0, unsigned long *value0,
 		    "=&r" ( index_borrow ),
 		    "+S" ( *value )
 		  : "S" ( *subtrahend ),
-		    "2" ( size ) );
+		    "2" ( size )
+		  : "cc" );
 
 	return ( -index_borrow );
 }
@@ -122,7 +124,8 @@ bigint_shl_raw ( unsigned long *value0, unsigned int size ) {
 		    "+S" ( *value )
 		  : "0" ( 0UL ),
 		    "2" ( size ),
-		    "3" ( 0U ) );
+		    "3" ( 0U )
+		  : "cc" );
 
 	return carry;
 }
@@ -155,7 +158,8 @@ bigint_shr_raw ( unsigned long *value0, unsigned int size ) {
 		    "=&r" ( carry ),
 		    "+S" ( *value )
 		  : "0" ( sizeof ( *value ) ),
-		    "2" ( 0 ) );
+		    "2" ( 0 )
+		  : "cc" );
 
 	return ( carry & 1 );
 }
@@ -183,7 +187,8 @@ bigint_grow_raw ( const unsigned long *source0, unsigned int source_size,
 		  "mvcle %0, %1, 0\n\t"
 		  "jo 1b\n\t"
 		  : "+r" ( dpair ), "+r" ( spair ), "=m" ( *dest )
-		  : "m" ( *source ) );
+		  : "m" ( *source )
+		  : "cc" );
 }
 
 /**
@@ -209,7 +214,8 @@ bigint_shrink_raw ( const unsigned long *source0, unsigned int source_size,
 		  "mvcle %0, %1, 0\n\t"
 		  "jo 1b\n\t"
 		  : "+r" ( dpair ), "+r" ( spair ), "=m" ( *dest )
-		  : "m" ( *source ) );
+		  : "m" ( *source )
+		  : "cc" );
 }
 
 /**
@@ -242,7 +248,8 @@ bigint_multiply_one ( const unsigned long multiplicand,
 		    "+T" ( *result ),
 		    "+r" ( *carry )
 		  : "r" ( multiplicand ),
-		    "r" ( multiplier ) );
+		    "r" ( multiplier )
+		  : "cc" );
 }
 
 #endif /* _BITS_BIGINT_H */
diff --git a/src/arch/s390x/include/bits/bitops.h b/src/arch/s390x/include/bits/bitops.h
index 2065ddbb8..d7c76629b 100644
--- a/src/arch/s390x/include/bits/bitops.h
+++ b/src/arch/s390x/include/bits/bitops.h
@@ -29,7 +29,8 @@ test_and_set_bit ( unsigned int bit, volatile void *bits ) {
 
 	__asm__ __volatile__ ( "lao %0, %2, %1"
 			       : "=r" ( old ), "+S" ( *word )
-			       : "r" ( mask ) );
+			       : "r" ( mask )
+			       : "cc" );
 
 	return ( !! ( old & mask ) );
 }
@@ -51,7 +52,8 @@ test_and_clear_bit ( unsigned int bit, volatile void *bits ) {
 
 	__asm__ __volatile__ ( "lan %0, %2, %1"
 			       : "=r" ( old ), "+S" ( *word )
-			       : "r" ( ~mask ) );
+			       : "r" ( ~mask )
+			       : "cc" );
 
 	return ( !! ( old & mask ) );
 }
diff --git a/src/arch/s390x/include/bits/profile.h b/src/arch/s390x/include/bits/profile.h
index b67934360..cf2ac6828 100644
--- a/src/arch/s390x/include/bits/profile.h
+++ b/src/arch/s390x/include/bits/profile.h
@@ -21,7 +21,7 @@ profile_timestamp ( void ) {
 	uint64_t cycles;
 
 	/* Read timestamp counter */
-	__asm__ ( "stckf %0" : "=Q" ( cycles ) );
+	__asm__ ( "stckf %0" : "=Q" ( cycles ) : : "cc" );
 	return cycles;
 }
 
diff --git a/src/arch/s390x/include/bits/string.h b/src/arch/s390x/include/bits/string.h
index 235a87819..b11e61168 100644
--- a/src/arch/s390x/include/bits/string.h
+++ b/src/arch/s390x/include/bits/string.h
@@ -34,21 +34,24 @@ memset ( void *dest, int character, size_t len ) {
 		/* Constant small length, zeroing: use XOR-in-place */
 		__asm__ ( "xc %O0(%1, %R0), %0"
 			  : "=Q" ( *dmem )
-			  : "i" ( len ) );
+			  : "i" ( len )
+			  : "cc" );
 	} else if ( __builtin_constant_p ( character ) ) {
 		/* Constant fill character: use "mvcle" with an immediate */
 		__asm__ ( "\n1:\n\t"
 			  "mvcle %0, %2, %3\n\t"
 			  "jo 1b\n\t"
 			  : "+r" ( dpair ), "=m" ( *dmem )
-			  : "r" ( spair ), "i" ( character ) );
+			  : "r" ( spair ), "i" ( character )
+			  : "cc" );
 	} else {
 		/* Variable fill character: use "mvcle" with a register */
 		__asm__ ( "\n1:\n\t"
 			  "mvcle %0, %2, 0(%3)\n\t"
 			  "jo 1b\n\t"
 			  : "+r" ( dpair ), "=m" ( *dmem )
-			  : "r" ( spair ), "a" ( character ) );
+			  : "r" ( spair ), "a" ( character )
+			  : "cc" );
 	}
 
 	return dest;
@@ -82,7 +85,8 @@ memcpy ( void *dest, const void *src, size_t len ) {
 			  "mvcle %0, %1, 0\n\t"
 			  "jo 1b\n\t"
 			  : "+r" ( dpair ), "+r" ( spair ), "=m" ( *dmem )
-			  : "m" ( *smem ) );
+			  : "m" ( *smem )
+			  : "cc" );
 	}
 
 	return dest;
diff --git a/src/arch/s390x/include/bits/strings.h b/src/arch/s390x/include/bits/strings.h
index 6fbe0e88c..48938280d 100644
--- a/src/arch/s390x/include/bits/strings.h
+++ b/src/arch/s390x/include/bits/strings.h
@@ -22,7 +22,7 @@ static inline __attribute__ (( always_inline )) int __ffsll ( long long value ){
 	value &= -value;
 
 	/* Count number of leading zeros before LSB */
-	__asm__ ( "flogr %0, %1" : "=r" ( pair ) : "r" ( value ) );
+	__asm__ ( "flogr %0, %1" : "=r" ( pair ) : "r" ( value ) : "cc" );
 
 	return ( 64 - pair.even );
 }
@@ -48,7 +48,7 @@ static inline __attribute__ (( always_inline )) int __flsll ( long long value ){
 	struct s390x_scalar_pair pair;
 
 	/* Count leading zeros */
-	__asm__ ( "flogr %0, %1" : "=r" ( pair ) : "r" ( value ) );
+	__asm__ ( "flogr %0, %1" : "=r" ( pair ) : "r" ( value ) : "cc" );
 	return ( 64 - pair.even );
 }
 
diff --git a/src/arch/s390x/include/bits/tcpip.h b/src/arch/s390x/include/bits/tcpip.h
index 423b1a176..b4f7734c8 100644
--- a/src/arch/s390x/include/bits/tcpip.h
+++ b/src/arch/s390x/include/bits/tcpip.h
@@ -33,7 +33,8 @@ tcpip_continue_chksum ( uint16_t partial, const void *data, size_t len ) {
 		  "alcr %0, %N1\n\t"
 		  : "=&r" ( cksum ),
 		    "+r" ( pair )
-		  : "0" ( ~partial ) );
+		  : "0" ( ~partial )
+		  : "cc" );
 
 	return ~cksum;
 }
diff --git a/src/arch/s390x/include/ipxe/tod.h b/src/arch/s390x/include/ipxe/tod.h
index 55c7ff5a7..73e0eb598 100644
--- a/src/arch/s390x/include/ipxe/tod.h
+++ b/src/arch/s390x/include/ipxe/tod.h
@@ -63,7 +63,7 @@ static inline unsigned long tod_ticks ( void ) {
 	union tod_extended tod;
 
 	/* Read clock */
-	__asm__ ( "stcke %0" : "=R" ( tod ) );
+	__asm__ ( "stcke %0" : "=R" ( tod ) : : "cc" );
 	return tod.ticks;
 }