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Date: Thu, 27 Sep 2018 06:28:43 -0700
From: Matthew Wilcox <willy@infradead.org>
To: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>,
        linux-fsdevel@vger.kernel.org, linux-nvdimm@lists.01.org,
        Barret Rhoden <brho@google.com>
Subject: Re: [PATCH] dax: Fix deadlock in dax_lock_mapping_entry()
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On Thu, Sep 27, 2018 at 01:23:32PM +0200, Jan Kara wrote:
> When dax_lock_mapping_entry() has to sleep to obtain entry lock, it will
> fail to unlock mapping->i_pages spinlock and thus immediately deadlock
> against itself when retrying to grab the entry lock again. Fix the
> problem by unlocking mapping->i_pages before retrying.

It seems weird that xfstests doesn't provoke this ...