Re: [Qemu-devel] [PATCH 1/3] virtio: Introduce VirtIODevice.broken

[Fam Zheng]

On Thu, 04/24 17:28, Michael S. Tsirkin wrote:
> On Thu, Apr 24, 2014 at 11:19:14AM +0800, Fam Zheng wrote:
> > On Wed, 04/23 10:17, Michael S. Tsirkin wrote:
> > > On Tue, Apr 22, 2014 at 04:55:15PM +0800, Fam Zheng wrote:
> > > > If guest driver behaves abnormally, emulation code could mark the device
> > > > as "broken".
> > > > 
> > > > Once "broken" is set, device emulation will typically wait for a reset
> > > > command and ignore any other operations, but it could also return error
> > > > responds. In other words, whether and how does guest know about this
> > > > error status is device specific.
> > > > 
> > > > Signed-off-by: Fam Zheng <address@hidden>
> > > 
> > > We really need a flag to notify guest about this state though.
> > > We should add this in virtio 1.0.
> > > For now, how about clearing DRIVER_OK?
> > 
> > >From Public Review Draft 02:
> > 
> >     DRIVER_OK (4) Indicates that the driver is set up and ready to drive the
> >     device.
> > 
> > Does clearing it here have any effect on guest behavior?
> > 
> > We could add a DEVICE_OK bit and let the driver check it before passing vq.
> 
> Could you please send this suggestion as review comment on the draft?
> We'll take it from here.

Doing that now.

Thanks,
Fam