From mboxrd@z Thu Jan  1 00:00:00 1970
From: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?=
	<u.kleine-koenig@pengutronix.de>
Subject: Re: [PATCH] fs: Work around NFS wreckage
Date: Thu, 13 Jan 2011 16:17:36 +0100
Message-ID: <20110113151736.GW24920@pengutronix.de>
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 <8952.1294927845@jrobl>
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Cc: Thomas Gleixner <tglx@linutronix.de>,
	Nick Piggin <npiggin@kernel.dk>,
	LKML <linux-kernel@vger.kernel.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	linux-fsdevel@vger.kernel.org,
	"Ramirez Luna, Omar" <omar.ramirez@ti.com>
To: "J. R. Okajima" <hooanon05@yahoo.co.jp>
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Hello,

On Thu, Jan 13, 2011 at 11:10:45PM +0900, 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" :=
)
>=20
> With this patch, can you unmount it cleanly?
> It skips incrementing d_count for both dentries.
> Do we need at least one?
If you tell me how to test that, I volunteer to try.
Something involving pivot_root?

Best regards
Uwe

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