From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Howells <dhowells@redhat.com>
Subject: Re: [PATCH 01/18] Add a dentry op to handle automounting rather than abusing follow_link()
Date: Fri, 14 Jan 2011 09:24:47 +0000
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	raven@themaw.net, autofs@linux.kernel.org,
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To: Nick Piggin <npiggin@gmail.com>
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Nick Piggin <npiggin@gmail.com> wrote:

> You still have to notice that it is .d_automount in rcu-walk mode, and bail
> out if it is. I can't see where you do that.

follow_managed(), and thus follow_automount() and ->d_automount(), are never
reached in rcu_walk mode, from what I can tell of the code.

There are two places follow_managed() is called:

 (1) do_lookup() - where follow_managed() is only called in the else-part of
     an if-statement contingent on a check of LOOKUP_RCU.

 (2) do_last() - where follow_managed() is subsequent to a mutex having been
     taken, so rcu-walk mode must have been exited prior to this as the
     process may have needed to sleep.

At least, I'm assuming you may not sleep whilst in rcu-walk mode.

David