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Date: Wed, 16 Dec 2009 08:04:31 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: linux-kernel@vger.kernel.org
Cc: Kay Sievers <kay.sievers@vrfy.org>, Greg Kroah-Hartman <gregkh@suse.de>
Subject: devtmpfs [censored] oddities
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	May I respectfully suggest that a blocking operation (such as
kstrdup with GFP_KERNEL, or grabbing a mutex, or, say it, pathname resolution)
is not quite the thing to do while holding an rwlock?

	As it is, any device_add() is an embarrassingly obvious deadlock
waiting to happen...