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From: Aneesh Kumar K.V <aneesh.kumar@kernel.org>
To: Nicholas Miehlbradt <nicholas@linux.ibm.com>, glider@google.com,
	elver@google.com, dvyukov@google.com, akpm@linux-foundation.org,
	mpe@ellerman.id.au, npiggin@gmail.com, christophe.leroy@csgroup.eu
Cc: linux-mm@kvack.org, kasan-dev@googlegroups.com, iii@linux.ibm.com,
	linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
	Nicholas Miehlbradt <nicholas@linux.ibm.com>
Subject: Re: [PATCH 09/13] powerpc: Disable KMSAN checks on functions which
 walk the stack
In-Reply-To: <20231214055539.9420-10-nicholas@linux.ibm.com>
References: <20231214055539.9420-1-nicholas@linux.ibm.com>
 <20231214055539.9420-10-nicholas@linux.ibm.com>
Date: Fri, 15 Dec 2023 14:32:02 +0530
Message-ID: <87wmtfu9dh.fsf@kernel.org>
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Nicholas Miehlbradt <nicholas@linux.ibm.com> writes:

> Functions which walk the stack read parts of the stack which cannot be
> instrumented by KMSAN e.g. the backchain. Disable KMSAN sanitization of
> these functions to prevent false positives.
>

Is the annotation needed to avoid uninitialized access check when
reading parts of the stack? Can you provide a false positive example for
the commit message?

-aneesh