[PATCH 5.10 078/125] s390/traps: do not test MONITOR CALL without CONFIG_BUG

From: Greg Kroah-Hartman
Date: Thu Jul 22 2021 - 12:42:05 EST


From: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>

[ Upstream commit b8e9cc20b808e26329090c19ff80b7f5098e98ff ]

tinyconfig fails to boot, because without CONFIG_BUG report_bug()
always returns BUG_TRAP_TYPE_BUG, which causes mc 0,0 in
test_monitor_call() to panic. Fix by skipping the test without
CONFIG_BUG.

Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
Reviewed-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/s390/kernel/traps.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c
index 8d1e8a1a97df..16934fa19069 100644
--- a/arch/s390/kernel/traps.c
+++ b/arch/s390/kernel/traps.c
@@ -272,6 +272,8 @@ static void __init test_monitor_call(void)
{
int val = 1;

+ if (!IS_ENABLED(CONFIG_BUG))
+ return;
asm volatile(
" mc 0,0\n"
"0: xgr %0,%0\n"
--
2.30.2