Re: [PATCH] Revert "null_blk: allow byte aligned memory offsets"

[Chaitanya Kulkarni <chaitanyak@nvidia.com>]

On 11/11/25 18:02, Keith Busch wrote:
> On Tue, Nov 11, 2025 at 02:08:33PM -0800, Bart Van Assche wrote:
>> This reverts commit 3451cf34f51bb70c24413abb20b423e64486161b and fixes
>> the following KASAN complaint when running test zbd/013
> Can I please just get one chance to fix it before a kneejerk revert??
>
> This was in v1, it was mistakenly dropped from v2.
>
> ---
> diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
> index f1e67962ecaeb..55c3f4d62c2e3 100644
> --- a/drivers/block/null_blk/main.c
> +++ b/drivers/block/null_blk/main.c
> @@ -1240,9 +1240,12 @@ static blk_status_t null_transfer(struct nullb *nullb, struct page *page,
>
>          p = kmap_local_page(page) + off;
>          if (!is_write) {
> -               if (dev->zoned)
> +               if (dev->zoned) {
>                          valid_len = null_zone_valid_read_len(nullb,
>                                  pos >> SECTOR_SHIFT, len);
> +                       if (valid_len != len)
> +                               valid_len -= (pos & (SECTOR_SIZE - 1));
> +               }
>
>                  if (valid_len) {
>                          copy_from_nullb(nullb, p, pos, valid_len);
> --


+1 on fix before revert,

-ck