Re: [PATCH] btrfs: return an error for unrepaired RAID56 scrub sectors

[Qu Wenruo <wqu@suse.com>]

在 2026/10/26 04:33, Cheng Yongkang 写道:
> scrub_raid56_parity_stripe() returns the leftover value of
> scrub_find_fill_first_stripe() (0 or 1) when it detects unrepaired
> sectors in a data stripe.  Scrub callers only treat negative values as
> errors, so the unrepaired state is masked as success and P/Q
> regeneration is skipped; a device replace can then copy corrupted data.
> 
> Return -EIO so the unrepaired sectors are reported and the corrupt
> stripe is not treated as healthy.
> 
> The masked-success behavior was reproduced 3/3 times: baseline scrub
> returned 0 with "finished ... status: 0", left P/Q unregenerated, and a
> device replace copied corruption.  With this change scrub returns -EIO
> and the replace is canceled; healthy RAID1/RAID5 scrub still succeeds.
> 
> Assisted-by: LLM
> Signed-off-by: Cheng Yongkang <teel4res@gmail.com>

Reviewed-by: Qu Wenruo <wqu@suse.com>

> ---
>   fs/btrfs/scrub.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
> index 479c0e0..ba2e27c 100644
> --- a/fs/btrfs/scrub.c
> +++ b/fs/btrfs/scrub.c
> @@ -2250,7 +2250,7 @@ static int scrub_raid56_parity_stripe(struct scrub_ctx *sctx,
>   "scrub: unrepaired sectors detected, full stripe %llu data stripe %u errors %*pbl",
>   				  full_stripe_start, i, stripe->nr_sectors,
>   				  &error);
> -			return ret;
> +			return -EIO;
>   		}
>   		bitmap_or(&extent_bitmap, &extent_bitmap, &has_extent,
>   			  stripe->nr_sectors);