Re: [Qemu-devel] [PATCH] migration: introduce migrate_is_blocked()

[Greg Kurz]

On Mon, 23 May 2016 21:42:23 +0530
Amit Shah <address@hidden> wrote:

> On (Wed) 11 May 2016 [14:10:34], Greg Kurz wrote:
> > On Wed, 11 May 2016 13:59:19 +0200
> > Paolo Bonzini <address@hidden> wrote:
> >   
> > > On 04/05/2016 21:44, Greg Kurz wrote:  
> > > > QEMU has currently two ways to prevent migration to occur:
> > > > - migration blocker when it depends on runtime state
> > > > - VMStateDescription.unmigratable when migration is not supported at all
> > > > 
> > > > This patch gathers all the logic into a single function to be called 
> > > > from
> > > > both the savevm and the migrate paths.
> > > > 
> > > > This fixes a bug with 9p, at least, where savevm would succeed and the
> > > > following would happen in the guest after loadvm:
> > > > 
> > > > $ ls /host
> > > > ls: cannot access /host: Protocol error
> > > > 
> > > > With this patch:
> > > > 
> > > > (qemu) savevm foo
> > > > Migration is disabled when VirtFS export path '/' is mounted in the 
> > > > guest
> > > > using mount_tag 'host'
> > > > 
> > > > Signed-off-by: Greg Kurz <address@hidden>
> > > > ---
> > > > 
> > > > Since there has been some activity on 9p again since a few weeks, maybe 
> > > > it
> > > > is not too late for 2.6, if everybody agrees the fix is ok ?    
> > > 
> > > The patch is good, but I think the subject should be
> > > 
> > >     savevm: fail if migration blockers are present
> > > 
> > > The subject you used would be good for the include/migration and
> > > migration/migration.c parts alone (where you introduce the function
> > > without any semantic change).
> > >   
> > 
> > Yeah, I agree the subject you are suggesting is far more informative :)  
> 
> I'll apply this with the suggested subject.
> 
> Please CC the migration maintainers for faster processing next time
> around.
> 

I had Cc'd Juan (who happens to be away) but I forgot your address... my bad :\

> Thanks,
> 
>               Amit
> 

Cheers !

--
Greg