Re: [f2fs-dev] [PATCH v2 1/2] f2fs: use BIT_ULL for mount option bitmasks

[Chao Yu]

On 9/11/26 22:35, Daeho Jeong wrote:
> From: Daeho Jeong <daehojeong@xxxxxxxxxx>
>
> Although f2fs_mount_info.opt and f2fs_fs_context.opt_mask are declared as
> unsigned long long (64 bits), the option bit manipulation macros
> (clear_opt, set_opt, test_opt) and context helpers (ctx_set_opt,
> ctx_clear_opt, ctx_test_opt) use BIT(), which expands to (UL(1) << nr).
>
> On 32-bit architectures, sizeof(unsigned long) is 32 bits, causing shift
> count overflow warnings and functional truncation if mount option indices
> reach or exceed 32.
>
> Replace BIT() with BIT_ULL() for mount option bitmasks and helpers.
> Additionally, introduce ctx_clear_opt_mask() and ctx_test_opt_mask()
> helpers to avoid open-coded bitwise manipulations on ctx->opt_mask.
>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-kbuild-all/202609111633.uyRbsEUB-lkp@xxxxxxxxx/
> Signed-off-by: Daeho Jeong <daehojeong@xxxxxxxxxx>

Reviewed-by: Chao Yu <chao@xxxxxxxxxx>

Thanks,