[PATCH v6] Add virtio SCMI device specification

[Russell King - ARM Linux admin]

On Fri, Feb 12, 2021 at 10:59:20AM +0100, Peter Hilber wrote:
> This patch proposes a new virtio device for the Arm SCMI protocol.
> 
> The device provides a simple transport for the Arm SCMI protocol[1]. The
> *S*ystem *C*ontrol and *M*anagement *I*nterface protocol allows speaking
> to system controllers that allow orchestrating things like power
> management, system state management and sensor access. The SCMI protocol
> is used on SoCs where multiple cores and co-processors need access to
> these resources.
> 
> The virtio transport allows making use of this protocol in virtualized
> systems.
> 
> [1] https://developer.arm.com/docs/den0056/c
> 
> Signed-off-by: Peter Hilber <peter.hilber at opensynergy.com>

I'm not too familiar with SCMI, but I think this question is worth
asking...

If the SCMI protocol can be used to control system level power
management, and if the intention is to expose this firmware interface
to virtualised guests, what prevents a guest from controlling the
power settings for stuff it should not have access to?

For example, if it's possible to tell the system to power down a
critical host component through SCMI, what would prevent a guest
requesting that critical component from having its power cut?

I hope I'm barking up the wrong tree...

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!