From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH 0/3] Fixes for vfs-scale and vfs-automount
Date: Thu, 24 Feb 2011 03:14:39 +0000
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Cc: Nick Piggin <npiggin@suse.de>,
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	David Howells <dhowells@redhat.com>,
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To: Ian Kent <raven@themaw.net>
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On Thu, Feb 24, 2011 at 11:03:38AM +0800, Ian Kent wrote:

> I also have a sick feeling that dentrys may become negative at any point
> after __d_lookup_rcu() .....

Yes.  To get stability of ->d_inode (assuming the sucker isn't pinned down
in normal way by ->d_count) you need ->d_lock.

> > Ho-hum...  I can reach RHTS, but I'd rather do that at home boxen, if
> > possible...  Has it been reproduced on UP boxen with SMP kernels, BTW?
> 
> Nope, I'd need to build a kernel specifically for that. I'm not sure how
> useful that would be though since the test is specifically meant to
> expose problems with multiple concurrent processes accessing an
> automount tree. I don't see any problem running the Connectathon tests
> which is essentially one automount and one client process.

Heh...  No, it's just that the only SMP box I have locally right now
is dual ultrasparc.  Anyway, I can live with RHTS.