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Date: Mon, 9 Apr 2018 06:51:04 -0700
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH] mm: workingset: fix NULL ptr dereference
Message-ID: <20180409135104.GA23434@infradead.org>
References: <20180409015815.235943-1-minchan@kernel.org>
 <20180409024925.GA21889@bombadil.infradead.org>
 <20180409030930.GA214930@rodete-desktop-imager.corp.google.com>
 <20180409111403.GA31652@bombadil.infradead.org>
 <20180409112514.GA195937@rodete-laptop-imager.corp.google.com>
 <7706245c-2661-f28b-f7f9-8f11e1ae932b@huawei.com>
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To: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>, Chao Yu <yuchao0@huawei.com>, Minchan Kim <minchan@kernel.org>, Jaegeuk Kim <jaegeuk@kernel.org>, Christopher Lameter <cl@linux.com>, Andrew Morton <akpm@linux-foundation.org>, linux-mm <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>, Johannes Weiner <hannes@cmpxchg.org>, Jan Kara <jack@suse.cz>, Chris Fries <cfries@google.com>, linux-f2fs-devel@lists.sourceforge.net, linux-fsdevel@vger.kernel.org

On Mon, Apr 09, 2018 at 06:41:14AM -0700, Matthew Wilcox wrote:
> It's worth noting that this is endemic in filesystems.

For the rationale in XFS take a look at commit ad22c7a043c2cc6792820e6c5da699935933e87d