Re: [virtio-comment] RE: [PATCH V2 3/6] virtio: dont reset vqs when SUSPEND

["Zhu, Lingshan" <lingshan.zhu@intel.com>]

On 11/22/2023 2:49 PM, Michael S. Tsirkin wrote:
> On Wed, Nov 22, 2023 at 09:51:45AM +0800, Zhu, Lingshan wrote:
> > On 11/22/2023 5:18 AM, Michael S. Tsirkin wrote:
> > > On Tue, Nov 21, 2023 at 03:33:07PM +0800, Jason Wang wrote:
> > > > > Lingshan claimed that suspending device is for live migration in commit log and in discussion he portray it as some basic facility unrelated to device migration such as debug etc.
> > > > > Instead of claiming it as some non_device_migration facility does not make sense.
> > > > It is used for migration for sure.
> > > Well having a generic facility to stop device sounds like a nice thing.
> > > However the devil is in the detail. A lot of detail here seems very much
> > > tailored to a very specific implementation in mind.
> > > So thinking through how it will work e.g. for power management
> > > would be a good excercise to figure out how it should work in detail.
> > > Parav did you indicate at some point a virtio specific SUSPEND
> > > bit can be useful for PM? Could you share how it's better than
> > > transport level PM and what the requirements are?
> > > Thanks!
> > Do you mean letting the device enter a new power state when SUSPEND,
> > and such description in transport-pci.tex? Then resume normal
> > state on DRIVER_OK.
> That would be one example.
OK, I will look into this.
Roughly say in transport-pci.tex: When SUSPEND, the device MAY 
optionally enter a
power-saving state.

Please allow me some time working on the details
>