Re: [RFC PATCH v1 0/8] Arm Core Local Accelerator Driver

[Ryan Roberts <ryan.roberts@arm.com>]

On 17/07/2026 13:09, Marc Zyngier wrote:
> Thanks Will for roping me in.

Sorry - I intentionally didn't include you because last time we spoke you said
you were only really interested in discussions on the virt side of things and I
didn't want to spam your inbox. Perhaps the wrong decision...

> 
> On Fri, 17 Jul 2026 12:33:17 +0100,
> Will Deacon <will@kernel.org> wrote:
>>
>>> I'm deliberately constraining the scope to bare-metal support for now.
>>> Virtualization is something we are considering (and have prototyped), but plan
>>> to post a separate RFC for that as follow-up, once we have agreement on
>>> direction for the bare-metal driver.
>>
>> I'd actually like to see what the virtualisation part looks like first
>> because doing it as a bolt-on later feels like the wrong approach. The
>> structure you have at the moment is remarkably clean, given the
>> architectural/CPU interactions (this thing even apparently builds as a
>> module, nice!), but I'm unsure how far you can push the separation once
>> you need to start hacking at KVM. Maybe the MMU notifiers are enough,
>> but I can't tell.
> 
> +1.
> 
> Virtualisation cannot be a "bolt on the side" exercise. It is an
> integral part of the arm64 tree, particularly for memory management
> and scheduling, all of which have a direct impact on KVM.
> 
> I don't think we can really evaluate anything here without looking at
> the full picture.

OK understood - as per reply to Will, we'll prioritise doing a version with virt
support.

Thanks,
Ryan


> 
> Thanks,
> 
> 	M.
>