[PATCH 4/9] s390/bug: Introduce and use monitor code macro

[Heiko Carstens <hca@linux.ibm.com>]

The first operand address of the monitor call (mc) instruction is the
monitor code. Currently the monitor code is ignored, but this will
change. Therefore add and use MONCODE_BUG instead of a hardcoded zero.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
---
 arch/s390/include/asm/bug.h | 10 ++++++++--
 arch/s390/kernel/traps.c    |  5 +++--
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/arch/s390/include/asm/bug.h b/arch/s390/include/asm/bug.h
index 5a635158cbad..1e1dece0eee4 100644
--- a/arch/s390/include/asm/bug.h
+++ b/arch/s390/include/asm/bug.h
@@ -3,7 +3,11 @@
 #define _ASM_S390_BUG_H
 
 #include <linux/compiler.h>
+#include <linux/const.h>
 
+#define	MONCODE_BUG	_AC(0, U)
+
+#ifndef __ASSEMBLER__
 #ifdef CONFIG_BUG
 
 #ifdef CONFIG_DEBUG_BUGVERBOSE
@@ -24,7 +28,7 @@
 #define __BUG_ASM(cond_str, flags)					\
 do {									\
 	asm_inline volatile("\n"					\
-		"0:	mc	0,0\n"					\
+		"0:	mc	%[monc](%%r0),0\n"			\
 		"	.section __bug_table,\"aw\"\n"			\
 		"1:	.long	0b - .	# bug_entry::bug_addr\n"	\
 		__BUG_ENTRY_VERBOSE("%[frmt]", "%[file]", "%[line]")	\
@@ -32,7 +36,8 @@ do {									\
 		"	.org	1b+%[size]\n"				\
 		"	.previous"					\
 		:							\
-		: [frmt] "i" (WARN_CONDITION_STR(cond_str)),		\
+		: [monc] "i" (MONCODE_BUG),				\
+		  [frmt] "i" (WARN_CONDITION_STR(cond_str)),		\
 		  [file] "i" (__FILE__),				\
 		  [line] "i" (__LINE__),				\
 		  [flgs] "i" (flags),					\
@@ -54,6 +59,7 @@ do {									\
 #define HAVE_ARCH_BUG_FORMAT
 
 #endif /* CONFIG_BUG */
+#endif /* __ASSEMBLER__ */
 
 #include <asm-generic/bug.h>
 
diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c
index 19687dab32f7..de63e98e724b 100644
--- a/arch/s390/kernel/traps.c
+++ b/arch/s390/kernel/traps.c
@@ -258,11 +258,12 @@ static void __init test_monitor_call(void)
 	if (!IS_ENABLED(CONFIG_BUG))
 		return;
 	asm_inline volatile(
-		"	mc	0,0\n"
+		"	mc	%[monc](%%r0),0\n"
 		"0:	lhi	%[val],0\n"
 		"1:\n"
 		EX_TABLE(0b, 1b)
-		: [val] "+d" (val));
+		: [val] "+d" (val)
+		: [monc] "i" (MONCODE_BUG));
 	if (!val)
 		panic("Monitor call doesn't work!\n");
 }
-- 
2.51.0