Re: [Qemu-devel] [Qemu-block] [PATCH v2 2/3] block/parallals: Do not update header or truncate image when INMIGRATE

[Jeff Cody <jcody@redhat.com>]

On Fri, Nov 03, 2017 at 02:08:13PM +0300, Denis V. Lunev wrote:
> On 11/03/2017 02:05 PM, Stefan Hajnoczi wrote:
> > On Mon, Oct 30, 2017 at 02:10:27PM +0100, Jeff Cody wrote:
> >> If we write or modify the image file while the QEMU run state is
> >> INMIGRATE, then the BDRV_O_INACTIVE BDS flag is set.  This will cause
> >> an assert, since the image is marked inactive.  Make sure we obey this
> >> flag.
> >>
> >> Signed-off-by: Jeff Cody <jcody@redhat.com>
> >> ---
> >>  block/parallels.c | 7 ++-----
> >>  1 file changed, 2 insertions(+), 5 deletions(-)
> >>
> >> diff --git a/block/parallels.c b/block/parallels.c
> >> index 2b6c6e5709..7b7a3efa1d 100644
> >> --- a/block/parallels.c
> >> +++ b/block/parallels.c
> >> @@ -708,7 +708,7 @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
> >>          s->prealloc_mode = PRL_PREALLOC_MODE_FALLOCATE;
> >>      }
> >>  
> >> -    if (flags & BDRV_O_RDWR) {
> >> +    if ((flags & BDRV_O_RDWR) && !(flags & BDRV_O_INACTIVE)) {
> >>          s->header->inuse = cpu_to_le32(HEADER_INUSE_MAGIC);
> >>          ret = parallels_update_header(bs);
> >>          if (ret < 0) {
> > Where do we ensure that HEADER_INUSE_MAGIC is set on the destination?
> good point. it should be set in invalidate_cache following QCOW2 scheme.
> Thus we should add that callback with this patch.
> 


Do we (intentionally) support migration with parallels?  I guess so, since
it doesn't have migration blockers.