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Date:   Tue, 29 Nov 2022 21:40:42 -0800
From:   Eric Biggers <ebiggers@kernel.org>
To:     Alexander Potapenko <glider@google.com>
Cc:     tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
        dave.hansen@linux.intel.com, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86: suppress KMSAN reports in arch_within_stack_frames()
Message-ID: <Y4bs2hoG3MANYgF7@sol.localdomain>
References: <20221118172305.3321253-1-glider@google.com>
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On Fri, Nov 18, 2022 at 06:23:05PM +0100, Alexander Potapenko wrote:
> arch_within_stack_frames() performs stack walking and may confuse
> KMSAN by stepping on stale shadow values. To prevent false positive
> reports, disable KMSAN checks in this function.
> 
> This fixes KMSAN's interoperability with CONFIG_HARDENED_USERCOPY.
> 
> Link: https://github.com/google/kmsan/issues/89
> Link: https://lore.kernel.org/lkml/Y3b9AAEKp2Vr3e6O@sol.localdomain/
> Cc: Eric Biggers <ebiggers@kernel.org>
> Signed-off-by: Alexander Potapenko <glider@google.com>
> ---
>  arch/x86/include/asm/thread_info.h | 5 +++++
>  1 file changed, 5 insertions(+)

Tested-by: Eric Biggers <ebiggers@google.com>

- Eric