Re: [PATCH v2] arm64: atomics: lse: Dereference matching size

From: Catalin Marinas
Date: Thu Jan 20 2022 - 10:56:29 EST


On Wed, 12 Jan 2022 12:22:59 -0800, Kees Cook wrote:
> When building with -Warray-bounds, the following warning is generated:
>
> In file included from ./arch/arm64/include/asm/lse.h:16,
> from ./arch/arm64/include/asm/cmpxchg.h:14,
> from ./arch/arm64/include/asm/atomic.h:16,
> from ./include/linux/atomic.h:7,
> from ./include/asm-generic/bitops/atomic.h:5,
> from ./arch/arm64/include/asm/bitops.h:25,
> from ./include/linux/bitops.h:33,
> from ./include/linux/kernel.h:22,
> from kernel/printk/printk.c:22:
> ./arch/arm64/include/asm/atomic_lse.h:247:9: warning: array subscript 'long unsigned int[0]' is partly outside array bounds of 'atomic_t[1]' [-Warray-bounds]
> 247 | asm volatile( \
> | ^~~
> ./arch/arm64/include/asm/atomic_lse.h:266:1: note: in expansion of macro '__CMPXCHG_CASE'
> 266 | __CMPXCHG_CASE(w, , acq_, 32, a, "memory")
> | ^~~~~~~~~~~~~~
> kernel/printk/printk.c:3606:17: note: while referencing 'printk_cpulock_owner'
> 3606 | static atomic_t printk_cpulock_owner = ATOMIC_INIT(-1);
> | ^~~~~~~~~~~~~~~~~~~~
>
> [...]

Applied to arm64 (for-next/core), thanks!

[1/1] arm64: atomics: lse: Dereference matching size
https://git.kernel.org/arm64/c/3364c6ce23c6

--
Catalin