[PATCH] arm64/mm: fix variable 'tag' set but not used

[Qian Cai]

When CONFIG_KASAN_SW_TAGS=n, set_tag() is compiled away. GCC throws a
warning,

mm/kasan/common.c: In function '__kasan_kmalloc':
mm/kasan/common.c:464:5: warning: variable 'tag' set but not used
[-Wunused-but-set-variable]
  u8 tag = 0xff;
     ^~~

Fix it by making __tag_set() a static inline function.

Signed-off-by: Qian Cai <c...@lca.pw>
---
 arch/arm64/include/asm/memory.h | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
index b7ba75809751..9645b1340afe 100644
--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -210,7 +210,11 @@ static inline unsigned long kaslr_offset(void)
 #define __tag_reset(addr)      untagged_addr(addr)
 #define __tag_get(addr)                (__u8)((u64)(addr) >> 56)
 #else
-#define __tag_set(addr, tag)   (addr)
+static inline const void *__tag_set(const void *addr, u8 tag)
+{
+       return addr;
+}
+
 #define __tag_reset(addr)      (addr)
 #define __tag_get(addr)                0
 #endif
-- 
1.8.3.1