Re: [PATCH] vfio: platform: Fix using devices in PM Domains

From: Simon Horman
Date: Thu Apr 12 2018 - 03:03:42 EST


On Wed, Apr 11, 2018 at 11:24:08AM +0200, Geert Uytterhoeven wrote:
> If a device is part of a PM Domain (e.g. power and/or clock domain), its
> power state is managed using Runtime PM. Without Runtime PM, the device
> may not be powered up, causing subtle failures, crashes, or system
> lock-ups when the device is accessed by the guest.
>
> Fix this by adding Runtime PM support, powering the device when the VFIO
> device is opened by the guest.
>
> Note that while more fine-grained power management could be implemented
> on the guest side, if exported, this would be inherently unsafe, as
> abusing it may kill the whole system.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

Reviewed-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>