From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Berg <johannes@sipsolutions.net>
Subject: Re: [patch 1/2] OSS: soundcard: locking bug in sound_ioctl()
Date: Mon, 11 Oct 2010 10:50:00 +0200
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	 <201010102039.34858.arnd@arndb.de>  <201010111013.28952.arnd@arndb.de>
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To: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <error27@gmail.com>, Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.de>, alsa-devel@alsa-project.org, kernel-janitors@vger.kernel.org, linux-sparse@vger.kernel.org, Josh Triplett <josh@kernel.org>

On Mon, 2010-10-11 at 10:13 +0200, Arnd Bergmann wrote:

> Hmm, actually sparse does *not* warn about sound_ioctl returning in
> different lock contexts. Sparse developers: is there a known limitation
> in sparse for this? I expected to see context warnings because
> sound_ioctl normally releases soundcard_mutex (previously lock_kernel)
> in some cases returns while holding the lock.

Arnd, mutexes aren't annotated in the kernel source to make use of
sparse's context checking.

johannes