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From: Arnd Bergmann <arnd@arndb.de>
To: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Subject: Re: [PATCH 2/3] input: use input_mutex instead of BKL when opening input device
Date: Tue, 9 Mar 2010 21:06:35 +0100
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Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>, linux-input@vger.kernel.org,
       linux-kernel@vger.kernel.org, John Kacur <jkacur@gmail.com>
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On Tuesday 09 March 2010, Thadeu Lima de Souza Cascardo wrote:
> There are three types of input character devices: mousedev, joydev and
> evdev. They all use the same major device and, then, their opening is
> multiplexed in input_open_file.
> 
> After the BKL pushdown, this multiplexing is protected by the BKL. But
> there's already a mutex used for adding and removing to the table
> indexed by input_open_file.
> 
> So, we use this mutex instead of the BKL. Since it will call the
> handlers' open function under the mutex, I've checked that the current
> functions do not call input_{un,}register_{handler,device}, which are
> the only other functions to take the mutex.
> 
> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>

Acked-by: Arnd Bergmann <arnd@arndb.de>