Re: [PATCH 3.4 11/26] md: Fix skipping recovery for read-onlyarrays.

From: NeilBrown
Date: Sun Nov 17 2013 - 02:21:41 EST


On Sun, 17 Nov 2013 04:11:19 +0000 Ben Hutchings <ben@xxxxxxxxxxxxxxx> wrote:

> On Fri, 2013-11-08 at 22:51 -0800, Greg Kroah-Hartman wrote:
> > 3.4-stable review patch. If anyone has any objections, please let me know.
> >
> > ------------------
> >
> > From: Lukasz Dorau <lukasz.dorau@xxxxxxxxx>
> >
> > commit 61e4947c99c4494336254ec540c50186d186150b upstream.
> >
> > Since:
> > commit 7ceb17e87bde79d285a8b988cfed9eaeebe60b86
> > md: Allow devices to be re-added to a read-only array.
> >
> > spares are activated on a read-only array. In case of raid1 and raid10
> > personalities it causes that not-in-sync devices are marked in-sync
> > without checking if recovery has been finished.
> >
> > If a read-only array is degraded and one of its devices is not in-sync
> > (because the array has been only partially recovered) recovery will be skipped.
> >
> > This patch adds checking if recovery has been finished before marking a device
> > in-sync for raid1 and raid10 personalities. In case of raid5 personality
> > such condition is already present (at raid5.c:6029).
> >
> > Bug was introduced in 3.10 and causes data corruption.
>
> So this fix was not needed for 3.4. Is it harmful if applied to this
> version?

It is not needed, but it is also not harmful.

NeilBrown


>
> Ben.
>
> > Signed-off-by: Pawel Baldysiak <pawel.baldysiak@xxxxxxxxx>
> > Signed-off-by: Lukasz Dorau <lukasz.dorau@xxxxxxxxx>
> > Signed-off-by: NeilBrown <neilb@xxxxxxx>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> >
> > ---
> > drivers/md/raid1.c | 1 +
> > drivers/md/raid10.c | 1 +
> > 2 files changed, 2 insertions(+)
> >
> > --- a/drivers/md/raid1.c
> > +++ b/drivers/md/raid1.c
> > @@ -1357,6 +1357,7 @@ static int raid1_spare_active(struct mdd
> > }
> > }
> > if (rdev
> > + && rdev->recovery_offset == MaxSector
> > && !test_bit(Faulty, &rdev->flags)
> > && !test_and_set_bit(In_sync, &rdev->flags)) {
> > count++;
> > --- a/drivers/md/raid10.c
> > +++ b/drivers/md/raid10.c
> > @@ -1534,6 +1534,7 @@ static int raid10_spare_active(struct md
> > }
> > sysfs_notify_dirent_safe(tmp->replacement->sysfs_state);
> > } else if (tmp->rdev
> > + && tmp->rdev->recovery_offset == MaxSector
> > && !test_bit(Faulty, &tmp->rdev->flags)
> > && !test_and_set_bit(In_sync, &tmp->rdev->flags)) {
> > count++;
>

Attachment: signature.asc
Description: PGP signature