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Date: Tue, 16 Feb 2016 17:43:24 +0100
Message-ID: <s5hy4ak61xv.wl-tiwai@suse.de>
From: Takashi Iwai <tiwai@suse.de>
To: Mark Brown <broonie@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>, linux-arm-kernel@lists.infradead.org,
        alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org,
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        Libin Yang <libin.yang@linux.intel.com>,
        Thierry Reding <treding@nvidia.com>,
        David Henningsson <david.henningsson@canonical.com>
Subject: Re: [PATCH] sound: hdmi: avoid dereferencing uninitialized 'jack' pointer
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On Tue, 16 Feb 2016 17:38:40 +0100,
Mark Brown wrote:
> 
> On Tue, Feb 16, 2016 at 05:18:29PM +0100, Takashi Iwai wrote:
> > Arnd Bergmann wrote:
> 
> > > Another option might would be to change snd_jack_new() to return
> > > an error if that SND_JACK is disabled, and then require all users
> > > to handle the error gracefully, i.e. not fail the probe() function
> > > but just not use the jack.
> 
> > Yes, I thought of that, too.  If select is no good option, it's a good
> > alternative, indeed.
> 
> It's going to be a bunch of work to implement though.

Is it?  Which driver would be broken?  Many ASoC drivers just ignore
the return error completely.  Some treats as a fatal error, and the
behavior would change, yes.  But I don't think that such a driver
would work without CONFIG_SND_JACK properly in anyway.


Takashi