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Date: Thu, 29 Sep 2016 13:17:13 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Anton Altaparmakov <anton@tuxera.com>
Cc: linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Race condition between iget_locked() and evict_inodes()
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On Thu, Sep 29, 2016 at 11:53:21AM +0000, Anton Altaparmakov wrote:
> Thus if the events happen in this order:
> 
> evict_inodes()				iget_locked() in find_inode_fast()

... you are buggered, because somebody is trying to grab a reference
to inode on a filesystem that is being shut down.  Look at evict_inode()
caller...