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Subject: Re: [PATCH v2 01/11] xen/manage: keep track of the on-going suspend mode
Date:   Tue, 21 Jul 2020 00:17:36 +0000
From:   Anchal Agarwal <anchalag@amazon.com>
To:     Roger Pau =?iso-8859-1?Q?Monn=E9?= <roger.pau@citrix.com>
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On Mon, Jul 20, 2020 at 11:37:05AM +0200, Roger Pau Monn? wrote:
> CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.
> 
> 
> 
> On Sat, Jul 18, 2020 at 09:47:04PM -0400, Boris Ostrovsky wrote:
> > (Roger, question for you at the very end)
> >
> > On 7/17/20 3:10 PM, Anchal Agarwal wrote:
> > > On Wed, Jul 15, 2020 at 05:18:08PM -0400, Boris Ostrovsky wrote:
> > >> CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.
> > >>
> > >>
> > >>
> > >> On 7/15/20 4:49 PM, Anchal Agarwal wrote:
> > >>> On Mon, Jul 13, 2020 at 11:52:01AM -0400, Boris Ostrovsky wrote:
> > >>>> CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.
> > >>>>
> > >>>>
> > >>>>
> > >>>> On 7/2/20 2:21 PM, Anchal Agarwal wrote:
> > >>>> And PVH dom0.
> > >>> That's another good use case to make it work with however, I still
> > >>> think that should be tested/worked upon separately as the feature itself
> > >>> (PVH Dom0) is very new.
> > >>
> > >> Same question here --- will this break PVH dom0?
> > >>
> > > I haven't tested it as a part of this series. Is that a blocker here?
> >
> >
> > I suspect dom0 will not do well now as far as hibernation goes, in which
> > case you are not breaking anything.
> >
> >
> > Roger?
> 
> I sadly don't have any box ATM that supports hibernation where I
> could test it. We have hibernation support for PV dom0, so while I
> haven't done anything specific to support or test hibernation on PVH
> dom0 I would at least aim to not make this any worse, and hence the
> check should at least also fail for a PVH dom0?
> 
> if (!xen_hvm_domain() || xen_initial_domain())
>     return -ENODEV;
> 
> Ie: none of this should be applied to a PVH dom0, as it doesn't have
> PV devices and hence should follow the bare metal device suspend.
>
So from what I understand you meant for any guest running on pvh dom0 should not 
hibernate if hibernation is triggered from within the guest or should they?

> Also I would contact the QubesOS guys, they rely heavily on the
> suspend feature for dom0, and that's something not currently tested by
> osstest so any breakages there go unnoticed.
> 
Was this for me or Boris? If its the former then I have no idea how to?
> Thanks, Roger.

Thanks,
Anchal