Re: [PATCH] arm64: efi: Fix KASAN false positive for EFI runtime stack

From: Breno Leitao
Date: Mon Jul 07 2025 - 12:09:37 EST



On Sun, Jul 06, 2025 at 07:45:04PM -0500, Catalin Marinas wrote:
> On Fri, Jul 04, 2025 at 02:40:17PM +0100, Mark Rutland wrote:
> > On Fri, Jul 04, 2025 at 02:33:35PM +0100, Will Deacon wrote:
> > > I would actually like to select VMAP_STACK unconditionally for arm64.
> > > Historically, we were held back waiting for all the various KASAN modes
> > > to support vmalloc properly, but I _think_ that's fixed now...
> > >
> > > The VMAP_STACK dependency is:
> > >
> > > depends on !KASAN || KASAN_HW_TAGS || KASAN_VMALLOC
> > >
> > > and in arm64 we have:
> > >
> > > select KASAN_VMALLOC if KASAN
> > >
> > > so it should be fine to select it afaict.
> > >
> > > Any reason not to do that?
> >
> > Not that I am aware of.
> >
> > I'm also in favour of unconditionally selecting VMAP_STACK.
>
> So am I.

Thanks. I've played a bit with it, and did some mechanical work, and
send a v1.

https://lore.kernel.org/all/20250707-arm64_vmap-v1-0-8de98ca0f91c@xxxxxxxxxx/