Re: [Qemu-devel] [PATCH v14 06/14] block: Add backing_blocker in BlockDriverState

[Fam Zheng <famz@redhat.com>]

On Wed, 02/19 16:17, Jeff Cody wrote:
> On Wed, Feb 19, 2014 at 09:42:23PM +0800, Fam Zheng wrote:
> > This makes use of op_blocker and blocks all the operations except for
> > commit target, on each BlockDriverState->backing_hd.
> > 
> > The asserts for op_blocker in bdrv_swap are removed because with this
> > change, the target of block commit has at least the backing blocker of
> > its child, so the assertion is not true. Callers should do their check.
> > 
> > Signed-off-by: Fam Zheng <famz@redhat.com>
> > ---
> >  block.c                   | 19 +++++++++++++++----
> >  include/block/block_int.h |  3 +++
> >  2 files changed, 18 insertions(+), 4 deletions(-)
> > 
> > diff --git a/block.c b/block.c
> > index dec44d4..95d8c1f 100644
> > --- a/block.c
> > +++ b/block.c
> > @@ -1044,19 +1044,33 @@ fail:
> >  void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
> >  {
> >      if (bs->backing_hd) {
> > +        assert(error_is_set(&bs->backing_blocker));
> 
> When I run block-commit, on either the active or non-active layer, I
> get an assertion here.  The qemu-iotests do not catch it, and I
> presume it is because happens a couple of seconds or so after the
> success message is returned over QMP.
> 

I can't reproduce this, could you give some specific steps? Thanks.

Fam