On Fri, Feb 21, 2025 at 04:11:06PM +0800, Zheng Qixing wrote:
> From: Zheng Qixing <zhengqixing@xxxxxxxxxx>
>
> The bad blocks check would miss bad blocks when retrying under contention,
> as checking parameters are not reset. These stale values from the previous
> attempt could lead to incorrect scanning in the subsequent retry.
>
> Move seqlock to outer function and reinitialize checking state for each
> retry. This ensures a clean state for each check attempt, preventing any
> missed bad blocks.
>
> Fixes: 3ea3354cb9f0 ("badblocks: improve badblocks_check() for multiple ranges handling")
> Signed-off-by: Zheng Qixing <zhengqixing@xxxxxxxxxx>
Looks good to me.
Acked-by: Coly Li <colyli@xxxxxxxxxx>
Thanks.
> ---
> block/badblocks.c | 50 +++++++++++++++++++++++------------------------
> 1 file changed, 24 insertions(+), 26 deletions(-)
>
> diff --git a/block/badblocks.c b/block/badblocks.c
> index 381f9db423d6..79d91be468c4 100644
> --- a/block/badblocks.c
> +++ b/block/badblocks.c
> @@ -1191,31 +1191,12 @@ static int _badblocks_clear(struct badblocks *bb, sector_t s, int sectors)
> static int _badblocks_check(struct badblocks *bb, sector_t s, int sectors,
> sector_t *first_bad, int *bad_sectors)
> {
> - int unacked_badblocks, acked_badblocks;
> int prev = -1, hint = -1, set = 0;
> struct badblocks_context bad;
> - unsigned int seq;
> + int unacked_badblocks = 0;
> + int acked_badblocks = 0;
> + u64 *p = bb->page;
> int len, rv;
> - u64 *p;
> -
> - WARN_ON(bb->shift < 0 || sectors == 0);
> -
> - if (bb->shift > 0) {
> - sector_t target;
> -
> - /* round the start down, and the end up */
> - target = s + sectors;
> - rounddown(s, 1 << bb->shift);
> - roundup(target, 1 << bb->shift);
> - sectors = target - s;
> - }
> -
> -retry:
> - seq = read_seqbegin(&bb->lock);
> -
> - p = bb->page;
> - unacked_badblocks = 0;
> - acked_badblocks = 0;
>
> re_check:
> bad.start = s;
> @@ -1281,9 +1262,6 @@ static int _badblocks_check(struct badblocks *bb, sector_t s, int sectors,
> else
> rv = 0;
>
> - if (read_seqretry(&bb->lock, seq))
> - goto retry;
> -
> return rv;
> }
>
> @@ -1324,7 +1302,27 @@ static int _badblocks_check(struct badblocks *bb, sector_t s, int sectors,
> int badblocks_check(struct badblocks *bb, sector_t s, int sectors,
> sector_t *first_bad, int *bad_sectors)
> {
> - return _badblocks_check(bb, s, sectors, first_bad, bad_sectors);
> + unsigned int seq;
> + int rv;
> +
> + WARN_ON(bb->shift < 0 || sectors == 0);
> +
> + if (bb->shift > 0) {
> + /* round the start down, and the end up */
> + sector_t target = s + sectors;
> +
> + rounddown(s, 1 << bb->shift);
> + roundup(target, 1 << bb->shift);
> + sectors = target - s;
> + }
> +
> +retry:
> + seq = read_seqbegin(&bb->lock);
> + rv = _badblocks_check(bb, s, sectors, first_bad, bad_sectors);
> + if (read_seqretry(&bb->lock, seq))
> + goto retry;
> +
> + return rv;
> }
> EXPORT_SYMBOL_GPL(badblocks_check);
>
> --
> 2.39.2
>
--
Coly Li
