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Subject: Re: [PATCH v2 01/11] xen/manage: keep track of the on-going suspend mode
Date:   Thu, 30 Jul 2020 23:06:34 +0000
From:   Anchal Agarwal <anchalag@amazon.com>
To:     Boris Ostrovsky <boris.ostrovsky@oracle.com>
CC:     Stefano Stabellini <sstabellini@kernel.org>, <tglx@linutronix.de>,
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On Mon, Jul 27, 2020 at 06:08:29PM -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 7/24/20 7:01 PM, Stefano Stabellini wrote:
> > Yes, it does, thank you. I'd rather not introduce unknown regressions so
> > I would recommend to add an arch-specific check on registering
> > freeze/thaw/restore handlers. Maybe something like the following:
> >
> > #ifdef CONFIG_X86
> >     .freeze = blkfront_freeze,
> >     .thaw = blkfront_restore,
> >     .restore = blkfront_restore
> > #endif
> >
> >
> > maybe Boris has a better suggestion on how to do it
> 
> 
> An alternative might be to still install pm notifier in
> drivers/xen/manage.c (I think as result of latest discussions we decided
> we won't need it) and return -ENOTSUPP for ARM for
> PM_HIBERNATION_PREPARE and friends. Would that work?
>
I think the question here is for registering driver specific freeze/thaw/restore
callbacks for x86 only. I have dropped the pm_notifier in the v3 still pending
testing. So I think just registering driver specific callbacks for x86 only is a
good option. What do you think?

Anchal
> 
> -boris
> 
> 
>