Re: [PATCH] mirror: Fix missed dirty bitmap writes during startup

[Kevin Wolf <kwolf@redhat.com>]

Am 02.03.2026 um 10:49 hat Jean-Louis Dupond geschrieben:
> 
> On 25/02/2026 13:32, Jean-Louis Dupond wrote:
> > 
> > On 24/02/2026 14:58, Kevin Wolf wrote:
> > > Am 20.02.2026 um 15:00 hat Fiona Ebner geschrieben:
> > > > Am 19.02.26 um 9:25 PM schrieb Kevin Wolf:
> > > > > @@ -1672,9 +1673,9 @@
> > > > > bdrv_mirror_top_do_write(BlockDriverState *bs, MirrorMethod
> > > > > method,
> > > > >           abort();
> > > > >       }
> > > > >   -    if (!copy_to_target && s->job && s->job->dirty_bitmap) {
> > > > > +    if (!copy_to_target) {
> > > > >           qatomic_set(&s->job->actively_synced, false);
> > > > Here, we must check that s->job is set for the qatomic_set().
> > > > 
> > > > Other than that, the patch looks good to me, thanks!
> > > Thanks, good catch. I'm squashing in this change:
> > > 
> > > diff --git a/block/mirror.c b/block/mirror.c
> > > index abdffc6de86..fa1d975eb9f 100644
> > > --- a/block/mirror.c
> > > +++ b/block/mirror.c
> > > @@ -1677,7 +1677,9 @@ bdrv_mirror_top_do_write(BlockDriverState *bs,
> > > MirrorMethod method,
> > >       }
> > > 
> > >       if (!copy_to_target) {
> > > -        qatomic_set(&s->job->actively_synced, false);
> > > +        if (s->job) {
> > > +            qatomic_set(&s->job->actively_synced, false);
> > > +        }
> > >           bdrv_set_dirty_bitmap(s->dirty_bitmap, offset, bytes);
> > >       }
> > > 
> > > Can I add your R-b with this?
> > > 
> > > Jean-Louis, do you want to give this patch a test if it still fixes your
> > > problem? The approach is a bit different from what we tried initially.
> > We are running our test case for +24hours now without any issue with
> > this patch included.
> > I am currently rebuilding el9 qemu with this patch included to run on
> > our production machines that had this corruption.
> > Let me come back in some days to fully confirm it's also fixed there :)
> Everything stays stable (without corruption), after a lot of servers in
> backup already with the patch.
> So therefor:
> 
> Tested-by: Jean-Louis Dupond <jean-louis@dupond.be>

Great, thanks for your testing!

Kevin