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Date: Fri, 4 Jul 2025 14:40:17 +0100
From: Mark Rutland <mark.rutland@arm.com>
To: Will Deacon <will@kernel.org>
Cc: Breno Leitao <leitao@debian.org>, Ard Biesheuvel <ardb@kernel.org>,
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Subject: Re: [PATCH] arm64: efi: Fix KASAN false positive for EFI runtime
 stack
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In-Reply-To: <aGfYL8eXjTA9puQr@willie-the-truck>

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.

Mark.