[PATCH v2 04/10] s390/runtime-const: Serialize text patching with text_mutex

[Heiko Carstens]

Acquire text_mutex inside runtime_const_fixup() around the patching
loop.

Serialization is not required for runtime_const_fixup(), however this is
part of larger series where at the end s390_kernel_write() requires that
callers hold text_mutex.

Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
---
 arch/s390/include/asm/runtime-const.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/s390/include/asm/runtime-const.h b/arch/s390/include/asm/runtime-const.h
index 7b71156031ec..0e2402717e8b 100644
--- a/arch/s390/include/asm/runtime-const.h
+++ b/arch/s390/include/asm/runtime-const.h
@@ -3,6 +3,7 @@
 #define _ASM_S390_RUNTIME_CONST_H
 
 #include <linux/uaccess.h>
+#include <linux/memory.h>
 
 #define runtime_const_ptr(sym)					\
 ({								\
@@ -88,6 +89,7 @@ static inline void __runtime_fixup_mask(void *where, unsigned long val)
 static inline void runtime_const_fixup(void (*fn)(void *, unsigned long),
 				       unsigned long val, s32 *start, s32 *end)
 {
+	guard(mutex)(&text_mutex);
 	while (start < end) {
 		fn(*start + (void *)start, val);
 		start++;
-- 
2.53.0