Re: [PATCH] device-assignment: Register as un-migratable

[Alex Williamson <alex.williamson@redhat.com>]

On Mon, 2010-11-15 at 21:05 +0100, Jan Kiszka wrote:
> Am 15.11.2010 20:41, Alex Williamson wrote:
> > Use register_device_unmigratable() to declare ourselves as
> > non-migratable.
> > 
> > Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
> > ---
> > 
> >  hw/device-assignment.c |   15 +++++++++++++++
> >  1 files changed, 15 insertions(+), 0 deletions(-)
> > 
> > diff --git a/hw/device-assignment.c b/hw/device-assignment.c
> > index bde231d..cd93941 100644
> > --- a/hw/device-assignment.c
> > +++ b/hw/device-assignment.c
> > @@ -1434,6 +1434,13 @@ static void assigned_dev_unregister_msix_mmio(AssignedDevice *dev)
> >      dev->msix_table_page = NULL;
> >  }
> >  
> > +/* This should never get called, but we're required to create a save_state
> > + * handler or else the no_migrate flag will never be checked. */
> > +static void assigned_save(QEMUFile* f, void *opaque)
> > +{
> > +    abort();
> > +}
> > +
> >  static int assigned_initfn(struct PCIDevice *pci_dev)
> >  {
> >      AssignedDevice *dev = DO_UPCAST(AssignedDevice, dev, pci_dev);
> > @@ -1490,6 +1497,13 @@ static int assigned_initfn(struct PCIDevice *pci_dev)
> >  
> >      assigned_dev_load_option_rom(dev);
> >      QLIST_INSERT_HEAD(&devs, dev, next);
> > +
> > +    /* Assigned devices are not migratable, register a save
> > +     * state entry so that we can mark it unmigratable. */
> > +    register_savevm(&dev->dev.qdev, "pci-assign", 0, 0,
> > +                    assigned_save, NULL, dev);
> > +    register_device_unmigratable(&dev->dev.qdev, "pci-assign", dev);
> > +
> 
> Isn't this expressible via some VMStateDescription? If not, that should
> be changed first.

Nope, save state handlers aren't allowed to fail.  I tried to fix it:

http://lists.nongnu.org/archive/html/qemu-devel/2010-11/msg00417.html

(you can find more discussion in other branches of that subject)  I've
succumbed to not getting that series in, so now I'm just trying to use
the code as it exists.  Thanks,

Alex