Re: [next-20260108]kernel BUG at drivers/scsi/scsi_lib.c:1173!

[Ming Lei <ming.lei@redhat.com>]

On Fri, Jan 09, 2026 at 05:14:36PM +0530, Venkat Rao Bagalkote wrote:
> 
> On 09/01/26 12:19 pm, Ming Lei wrote:
> > On Thu, Jan 08, 2026 at 09:56:39PM -0800, Christoph Hellwig wrote:
> > > I've seen the same when running xfstests on xfs, and bisected it to:
> > > 
> > > commit ee623c892aa59003fca173de0041abc2ccc2c72d
> > > Author: Ming Lei <ming.lei@redhat.com>
> > > Date:   Wed Dec 31 11:00:55 2025 +0800
> > > 
> > >      block: use bvec iterator helper for bio_may_need_split()
> > > 
> > Hi Christoph and Venkat Rao Bagalkote,
> > 
> > Unfortunately I can't duplicate the issue in my environment, can you test
> > the following patch?
> > 
> > diff --git a/block/blk.h b/block/blk.h
> > index 98f4dfd4ec75..980eef1f5690 100644
> > --- a/block/blk.h
> > +++ b/block/blk.h
> > @@ -380,7 +380,7 @@ static inline bool bio_may_need_split(struct bio *bio,
> >                  return true;
> >          bv = __bvec_iter_bvec(bio->bi_io_vec, bio->bi_iter);
> > -       if (bio->bi_iter.bi_size > bv->bv_len)
> > +       if (bio->bi_iter.bi_size > bv->bv_len - bio->bi_iter.bi_bvec_done)
> >                  return true;
> >          return bv->bv_len + bv->bv_offset > lim->max_fast_segment_size;
> >   }
> 
> Hello Ming,
> 
> 
> This is not helping. I am hitting this issue, during kernel build itself.

Can you confirm if it can fix the blktests ext4/056 first?

If kernel building is running over new patched kernel, please provide the
dmesg log. And if it is reproduciable, can you confirm if it can be fixed
by reverting ee623c892aa59003 (block: use bvec iterator helper for bio_may_need_split())?


Thanks,
Ming