From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: ->d_lock FUBAR (was Re: Linux 3.0-rc6)
Date: Wed, 13 Jul 2011 04:22:39 +0100
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On Wed, Jul 13, 2011 at 03:59:18AM +0100, Al Viro wrote:

> I'm not sure how much do we care about stability of x->d_parent when
> x->d_lock is held.  ->d_compare() is the most obvious potential area
> of trouble in that respect, but there might be more.

Oh, and another fun area is per-chain locks, of course ;-/  Look at
__d_drop(); reengineering the callers of d_drop() to make sure that
fscker's parent stays stable would be very painful and turning that
into loop-based variant is going to be interesting.  Doable, but not
fun...