Re: [PATCH 6/6] xfs: bail out on bitmap errors in xrep_agfl_fill

["Darrick J. Wong" <djwong@kernel.org>]

On Fri, Sep 04, 2026 at 09:38:59AM +0200, Carlos Maiolino wrote:
> On Thu, Sep 03, 2026 at 11:27:19PM -0700, Darrick J. Wong wrote:
> > From: Darrick J. Wong <djwong@kernel.org>
> > 
> > LOLLM also points out that the xagb_bitmap_set call in xrep_agfl_fill
> > can fail, but we don't check the result of xagb_bitmap_walk, so we
> > silently drop the error and proceed with inconsistent incore data.
> > That shouldn't be allowed.
> 
> Looks good.
> 
> > 
> > While we're at it, fix leaking the used_extents bitmap if the disunion
> > operation fails.
> 
> Smells this description belongs to the previous patch?

Yeah, that belongs in "xfs: snapshot old AGFL before rewriting it".
I'll move this sentence to there.

--D

> > 
> > Cc: <stable@vger.kernel.org> # v6.6
> > Fixes: 014ad53732d2ba ("xfs: use per-AG bitmaps to reap unused AG metadata blocks during repair")
> > Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
> > Assisted-by: LOLLM # finding obvious bugs
> > ---
> >  fs/xfs/scrub/agheader_repair.c |    4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > 
> > diff --git a/fs/xfs/scrub/agheader_repair.c b/fs/xfs/scrub/agheader_repair.c
> > index 46c95354ca6438..a66b611588c47f 100644
> > --- a/fs/xfs/scrub/agheader_repair.c
> > +++ b/fs/xfs/scrub/agheader_repair.c
> > @@ -699,7 +699,9 @@ xrep_agfl_init_header(
> >  	 */
> >  	xagb_bitmap_init(&af.used_extents);
> >  	af.agfl_bno = xfs_buf_to_agfl_bno(agfl_bp);
> > -	xagb_bitmap_walk(agfl_extents, xrep_agfl_fill, &af);
> > +	error = xagb_bitmap_walk(agfl_extents, xrep_agfl_fill, &af);
> > +	if (error && error != -ECANCELED)
> > +		goto err_undo;
> >  	error = xagb_bitmap_disunion(agfl_extents, &af.used_extents);
> >  	if (error)
> >  		goto err_undo;
> > 
> > 
>