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| author | Kees Cook <keescook@chromium.org> | 2022-02-03 01:48:34 +0300 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2022-02-14 03:48:04 +0300 |
| commit | 2a55550fbba643f41318bb12ab20e6510c7df231 (patch) | |
| tree | e94c670ef14997f33b3dbfa82d3b0c29b6eab5cf /arch/m68k | |
| parent | 9ed0a59c0cbb663ea09588322498499a937d08fa (diff) | |
| download | linux-2a55550fbba643f41318bb12ab20e6510c7df231.tar.xz | |
m68k: cmpxchg: Dereference matching size
Similar to the recent arm64 fix[1], avoid overly wide casts in the m68k
cmpxchg implementation. Avoids this warning under -Warray-bounds with
GCC 11:
net/sched/cls_tcindex.c: In function 'tcindex_set_parms':
./arch/m68k/include/asm/cmpxchg.h:64:17: warning: array subscript 'volatile struct __xchg_dummy[0]' is partly outside array bounds of 'struct tcf_result[1]' [-Warray-bounds]
64 | __asm__ __volatile__
| ^~~~~~~
net/sched/cls_tcindex.c:338:27: note: while referencing 'cr'
338 | struct tcf_result cr = {};
| ^~
No binary output difference are seen from this change.
[1] commit 3364c6ce23c6 ("arm64: atomics: lse: Dereference matching size")
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/lkml/CAMuHMdVRrD+2zKoHxAaQdDuiK5JFDanbv0SJ91OdWfx+eyekPQ@mail.gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Diffstat (limited to 'arch/m68k')
| -rw-r--r-- | arch/m68k/include/asm/cmpxchg.h | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/arch/m68k/include/asm/cmpxchg.h b/arch/m68k/include/asm/cmpxchg.h index e8ca4b0ccefa..6cf464cdab06 100644 --- a/arch/m68k/include/asm/cmpxchg.h +++ b/arch/m68k/include/asm/cmpxchg.h @@ -4,8 +4,7 @@ #include <linux/irqflags.h> -struct __xchg_dummy { unsigned long a[100]; }; -#define __xg(x) ((volatile struct __xchg_dummy *)(x)) +#define __xg(type, x) ((volatile type *)(x)) extern unsigned long __invalid_xchg_size(unsigned long, volatile void *, int); @@ -50,7 +49,7 @@ static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int siz "1:\n\t" "casb %0,%1,%2\n\t" "jne 1b" - : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); + : "=&d" (x) : "d" (x), "m" (*__xg(u8, ptr)) : "memory"); break; case 2: __asm__ __volatile__ @@ -58,7 +57,7 @@ static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int siz "1:\n\t" "casw %0,%1,%2\n\t" "jne 1b" - : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); + : "=&d" (x) : "d" (x), "m" (*__xg(u16, ptr)) : "memory"); break; case 4: __asm__ __volatile__ @@ -66,7 +65,7 @@ static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int siz "1:\n\t" "casl %0,%1,%2\n\t" "jne 1b" - : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); + : "=&d" (x) : "d" (x), "m" (*__xg(u32, ptr)) : "memory"); break; default: x = __invalid_xchg_size(x, ptr, size); |