From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arnd Bergmann <arnd@arndb.de>
Date: Mon, 11 Oct 2010 10:50:16 +0000
Subject: Re: [patch 1/2] OSS: soundcard: locking bug in sound_ioctl()
Message-Id: <201010111250.16299.arnd@arndb.de>
List-Id: <kernel-janitors.vger.kernel.org>
References: <20101010173352.GB5851@bicker> <201010111013.28952.arnd@arndb.de> <1286787000.3634.1.camel@jlt3.sipsolutions.net>
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To: Johannes Berg <johannes@sipsolutions.net>
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 Monday 11 October 2010, Johannes Berg wrote:
> 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.

D'oh. I never realized this was only done for some types of locks.
Is there a reason why we don't want mutexes to be annotated or do
we just need someone to do it?

	Arnd