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From: Oliver Neukum <oliver@neukum.org>
To: Jiri Kosina <jkosina@suse.cz>
Subject: Re: [PATCH 4/5] usb:Push BKL on open down into the drivers
Date: Mon, 29 Mar 2010 15:30:36 +0200
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Cc: Greg KH <greg@kroah.com>, USB list <linux-usb@vger.kernel.org>,
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Am Montag 29 März 2010 12:04:51 schrieb Jiri Kosina:
> For hiddev, this causes a problem, as you introduced BKL into 
> hiddev_connect() exactly because of the proper dependency -- we have the 
> BKL there to avoid race after usb_register_dev() -- once the device node 
> has been created, open() could happen on it.

Hi,

it seems to me you cannot deadlock with the BKL and an rwsem,
as BKL will be dropped if a task blocks on the rwsem. This is not
a nice feature of the BKL to use. Do you have an alternative idea?

	Regards
		Oliver