Re: [PATCH] md/raid1-10: shut up randstruct warning again

[Yu Kuai <yukuai1@huaweicloud.com>]

Hi,

在 2023/06/16 17:24, Arnd Bergmann 写道:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> A code reorganization brought back a warning when structure randomization
> is enabled:
> 
> drivers/md/raid1-10.c:119:25: error: casting from randomized structure pointer type 'struct block_device *' to 'struct md_rdev *'
>          struct md_rdev *rdev = (struct md_rdev *)bio->bi_bdev;
>                                 ^
> 
> Before the rework, this used a (void*) cast, so go back to that in order
> to avoid the warning. Casting between pointers to incompatible types is
> clearly something that is dangerous, but this driver has always done so,
> and it's not made any worse by the struct randomization in this case.
> 
> Fixes: 8295efbe68c08 ("md/raid1-10: factor out a helper to submit normal write")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Thanks for the patch, and this problem is already reported by kernel
test robot:

https://lore.kernel.org/oe-kbuild-all/202306142042.fmjfmTF8-lkp@intel.com/

And fixed patch is already applied:

https://lore.kernel.org/lkml/CAPhsuW6aSvCEa1khjjmDYGozUEs+Tx75RxfaE1+xL2Y1T6aN=Q@mail.gmail.com/T/

Thanks,
Kuai
> ---
>   drivers/md/raid1-10.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/md/raid1-10.c b/drivers/md/raid1-10.c
> index 169ebe296f2d0..3f22edec70e78 100644
> --- a/drivers/md/raid1-10.c
> +++ b/drivers/md/raid1-10.c
> @@ -116,7 +116,7 @@ static void md_bio_reset_resync_pages(struct bio *bio, struct resync_pages *rp,
>   
>   static inline void raid1_submit_write(struct bio *bio)
>   {
> -	struct md_rdev *rdev = (struct md_rdev *)bio->bi_bdev;
> +	struct md_rdev *rdev = (void *)bio->bi_bdev;
>   
>   	bio->bi_next = NULL;
>   	bio_set_dev(bio, rdev->bdev);
>