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Date: Thu, 13 Jan 2011 17:41:58 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: "J. R. Okajima" <hooanon05@yahoo.co.jp>
cc: Nick Piggin <npiggin@kernel.dk>, LKML <linux-kernel@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-fsdevel@vger.kernel.org, u.kleine-koenig@pengutronix.de,
        "Ramirez Luna, Omar" <omar.ramirez@ti.com>
Subject: Re: [PATCH] fs: Work around NFS wreckage
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On Thu, 13 Jan 2011, J. R. Okajima wrote:
> Thomas Gleixner:
> > The dcache scalability work broke NFS root filesystems.
> 	:::
> > Check for parent equal dentry and skip the nested lock to avoid the
> > deadlock. I'm sure this is the wrong fix, but at least it "works" :)
> 
> With this patch, can you unmount it cleanly?
> It skips incrementing d_count for both dentries.
> Do we need at least one?

Not sure, as we should not end up there at all I guess.