Date:   Fri, 12 Nov 2021 10:56:26 -0800
From:   Eric Biggers <ebiggers@kernel.org>
To:     Roberto Sassu <roberto.sassu@huawei.com>
Cc:     tytso@mit.edu, corbet@lwn.net, viro@zeniv.linux.org.uk,
        hughd@google.com, akpm@linux-foundation.org,
        linux-fscrypt@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
        linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC][PATCH 4/5] shmem: Avoid segfault in
 shmem_read_mapping_page_gfp()
Message-ID: <YY642nxarVElvKUS@gmail.com>
References: <20211112124411.1948809-1-roberto.sassu@huawei.com>
 <20211112124411.1948809-5-roberto.sassu@huawei.com>
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On Fri, Nov 12, 2021 at 01:44:10PM +0100, Roberto Sassu wrote:
> Check the hwpoison page flag only if the page is valid in
> shmem_read_mapping_page_gfp(). The PageHWPoison() macro tries to access
> the page flags and cannot work on an error pointer.
> 
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>

This looks like a recent regression from the commit:

	commit b9d02f1bdd98f38e6e5ecacc9786a8f58f3f8b2c
	Author: Yang Shi <shy828301@gmail.com>
	Date:   Fri Nov 5 13:41:10 2021 -0700

	    mm: shmem: don't truncate page if memory failure happens

Can you please send this fix out as a standalone patch, to the right people and
including the appropriate "Fixes" tag?

- Eric