[dm-devel] [PATCH] md/raid0: Fail BIOs if their underlying block device is gone

[Song Liu]

On Wed, Jul 31, 2019 at 12:54 PM Song Liu <liu.song.a23 at gmail.com> wrote:
>
> On Tue, Jul 30, 2019 at 5:31 AM Guilherme G. Piccoli
> <gpiccoli at canonical.com> wrote:
> >
> > On 29/07/2019 21:08, NeilBrown wrote:
> > >[...]
> > >> +    if (unlikely(test_bit(MD_BROKEN, &mddev->flags))) {
> > >> +            bio_io_error(bio);
> > >> +            return BLK_QC_T_NONE;
> > >> +    }
> > >
> > > I think this should only fail WRITE requests, not READ requests.
> > >
> > > Otherwise the patch is probably reasonable.
> > >
> > > NeilBrown
> >
> > Thanks for the feedback Neil! I thought about it; it seemed to me better
> > to deny/fail the reads instead of returning "wrong" reads, since a file
> > read in a raid0 will be incomplete if one member is missing.
> > But it's fine for me to change that in the next iteration of this patch.
>
> For reads at block/page level, we will either get EIO or valid data, right?
>
> If that's not the case, we should fail all writes.

Oops, I meant all _reads_.

>
> Thanks,
> Song