Re: [PATCH RFC v2 14/27] arm64: mte: Disable dynamic tag storage management if HW KASAN is enabled

From: Alexandru Elisei
Date: Mon Nov 27 2023 - 10:07:38 EST


Hi,

On Fri, Nov 24, 2023 at 08:54:12PM +0100, David Hildenbrand wrote:
> On 19.11.23 17:57, Alexandru Elisei wrote:
> > To be able to reserve the tag storage associated with a page requires that
> > the tag storage page can be migrated.
> >
> > When HW KASAN is enabled, the kernel allocates pages, which are now tagged,
> > in non-preemptible contexts, which can make reserving the associate tag
> > storage impossible.
>
> I assume that it's the only in-kernel user that actually requires tagged
> memory (besides for user space), correct?

Indeed, this is the case. I'll expand the commit message to be more clear about
it.

Thanks,
Alex

>
> --
> Cheers,
>
> David / dhildenb
>