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Date:   Thu, 25 Apr 2019 19:21:00 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Ilya Dryomov <idryomov@gmail.com>,
        Jeff Layton <jlayton@kernel.org>, ceph-devel@vger.kernel.org,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>
Subject: Re: [GIT PULL] Ceph fixes for 5.1-rc7
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On Thu, Apr 25, 2019 at 11:02:54AM -0700, Linus Torvalds wrote:

> I've pulled this, but maybe Jeff wants to look at whether that
> snapshotting model could have helped.

I really wonder if 76a495d666e5 (ceph: ensure d_name stability in
ceph_dentry_hash()) makes any sense; OK, you have ->d_lock held
over that, but what does it protect against?  Sure, you'll get
something that was valid while you held ->d_lock, but what good
does it do to the callers?  If they really have to care about
races with d_move(), which value do they want?