linux-kernel - Re: [PATCH v2 01/11] ASoC: samsung: s3c2412: Handle return value of clk_prepare

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 26 Jul 2017 15:47:12 +0100
From:   Mark Brown <broonie@...nel.org>
To:     Arvind Yadav <arvind.yadav.cs@...il.com>
Cc:     perex@...ex.cz, tiwai@...e.com, krzk@...nel.org,
        sbkim73@...sung.com, lgirdwood@...il.com,
        alsa-devel@...a-project.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 01/11] ASoC: samsung: s3c2412: Handle return value of
 clk_prepare_enable.

On Wed, Jul 26, 2017 at 05:35:32PM +0530, Arvind Yadav wrote:
> On Wednesday 26 July 2017 04:58 PM, Mark Brown wrote:
> > On Wed, Jul 26, 2017 at 11:15:25AM +0530, Arvind Yadav wrote:

> > > +err:
> > > +	clk_disable(s3c2412_i2s.iis_pclk);
> > This will disable the clock if we failed to enable it which is clearly
> > not correct.  It's also matching a clk_prepare_enable() with a
> > clk_disable() which is going to leave an unbalanced prepare.

> s3c_i2sv2_probe is enabling "iis" clock. And s3c2412_i2s_probe is enabling
> "i2sclk"  and "mpll"clock. If, "mpll" clk_prepare_enable fails. We need to
> disable and
> free the clock "iis".  and devm will handle other clock "i2sclk". In this
> code we have used
> "s3c2412_i2s.iis_cclk" for all the clock which is more confusing for me.
> Please correct me if i am wrong.

OK, they are different clocks.  This inconsistent handling seems like a
big part of the problem though - it's going to be a source of errors.
We're also still only disabling here, not unpreparing, so we're missing
something.

Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)