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Date: Sun, 6 Jul 2025 19:45:04 -0500
From: Catalin Marinas <catalin.marinas@arm.com>
To: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>, Breno Leitao <leitao@debian.org>,
	Ard Biesheuvel <ardb@kernel.org>, usamaarif642@gmail.com,
	rmikey@meta.com, andreyknvl@gmail.com, kasan-dev@googlegroups.com,
	linux-efi@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, kernel-team@meta.com
Subject: Re: [PATCH] arm64: efi: Fix KASAN false positive for EFI runtime
 stack
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In-Reply-To: <aGfZwTCNO_10Ceng@J2N7QTR9R3>

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.

-- 
Catalin