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Subject: Re: [PATCH v2 01/11] xen/manage: keep track of the on-going suspend mode
Date:   Wed, 5 Aug 2020 17:42:19 +0000
From:   Anchal Agarwal <anchalag@amazon.com>
To:     Boris Ostrovsky <boris.ostrovsky@oracle.com>
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On Wed, Aug 05, 2020 at 09:31:13AM -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 8/4/20 7:42 PM, Anchal Agarwal wrote:
> >
> > I think this could be done. PM_HIBERNATION_PREPARE could return -ENOTSUPP
> > for arm and pvh dom0 when the notifier call chain is invoked for this case
> > in hibernate(). This will then be an empty notifier just for checking two
> > usecases.
> > Also, for pvh dom0, the earlier code didn't register any notifier,
> > with this approach you are suggesting setup the notifier for hvm/pvh dom0 and
> > arm but fail during notifier call chain during PM_HIBERNATION_PREPARE ?
> 
> 
> Right.
> 
> 
> (Although the earlier code did register the notifier:
> xen_setup_pm_notifier() would return an error for !xen_hvm_domain() and
> PVH *is* an HVM domain, so registration would actually happen)
>
Yes you are right. My bad, what I meant with "earlier code" was whatever we
discussed w.r.t to removing the notifier all together, it won't be registered for
pvh dom0.
Anyways got the point :)
> 
> >
> > I think still getting rid of suspend mode that was earlier a part of this
> > notifier is a good idea as it seems redundant as you pointed out earlier.
> 
> 
> Yes.
> 
> 
> -boris
Thanks,
Anchal
> 
>