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Date:   Wed, 27 Jul 2022 14:29:13 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Yongqiang Liu <liuyongqiang13@huawei.com>
Cc:     dhowells@redhat.com, akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, zhangxiaoxu5@huawei.com,
        yanaijie@huawei.com, vbabka@suse.cz, wangkefeng.wang@huawei.com
Subject: Re: [PATCH] mm/folio-compact: fix potential NULL pointer in
 pagecache_get_page
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On Wed, Jul 27, 2022 at 06:46:21AM +0000, Yongqiang Liu wrote:
> When __filemap_get_folio() failed and returned NULL, we would
> get a NULL pointer dereference in pagecache_get_page.

No we wouldn't.