Re: [PATCH v3 12/14] arm64: realm: Support nonsecure ITS emulation shared

From: Catalin Marinas
Date: Fri Jun 07 2024 - 12:46:55 EST


On Fri, Jun 07, 2024 at 04:45:14PM +0100, Steven Price wrote:
> On 06/06/2024 19:38, Catalin Marinas wrote:
> > Anyway, we could do some hacking around gen_pool as a temporary solution
> > (maybe as a set of patches on top of this series to be easier to revert)
> > and start investigating a proper decrypted page allocator in parallel.
> > We just need to find a victim that has the page allocator fresh in mind
> > (Ryan or Alexandru ;)).
>
> Thanks for the suggestions Catalin. I had a go at implementing something
> with gen_pool - the below (very lightly tested) hack seems to work. This
> is on top of the current series.
>
> I *think* it should also be safe to drop the whole alignment part with
> this custom allocator, which could actually save memory. But I haven't
> quite got my head around that yet.

Thanks Steven. It doesn't look too complex and it solves the memory
wasting. We don't actually free the pages from gen_pool but I don't
think it matters much, the memory would get reused if devices are
removed and re-added.

--
Catalin