linux-kernel - Re: [alsa-devel] [PATCH v2] soundwire: stream: fix bad unlock balance

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Date:   Thu, 6 Jun 2019 22:37:50 +0530
From:   Sanyog Kale <sanyog.r.kale@...el.com>
To:     Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>
Cc:     Srinivas Kandagatla <srinivas.kandagatla@...aro.org>,
        vkoul@...nel.org, alsa-devel@...a-project.org,
        linux-kernel@...r.kernel.org
Subject: Re: [alsa-devel] [PATCH v2] soundwire: stream: fix bad unlock balance

On Thu, Jun 06, 2019 at 10:36:02AM -0500, Pierre-Louis Bossart wrote:
> On 6/6/19 9:58 AM, Srinivas Kandagatla wrote:
> > 
> > 
> > On 06/06/2019 15:28, Pierre-Louis Bossart wrote:
> > > On 6/6/19 6:22 AM, Srinivas Kandagatla wrote:
> > > > multi bank switching code takes lock on condition but releases without
> > > > any check resulting in below warning.
> > > > This patch fixes this.
> > > 
> > > 
> > > Question to make sure we are talking about the same thing:
> > > multi-link bank switching is a capability beyond the scope of the
> > > SoundWire spec which requires hardware support to synchronize links
> > > and as Sanyog hinted at in a previous email follow a different flow
> > > for bank switches.
> > > 
> > > You would not use the multi-link mode if you have different links
> > > that can operate independently and have no synchronization
> > > requirement. You would conversely use the multi-link mode if you
> > > have two devices on the same type on different links and want audio
> > > to be rendered at the same time.
> > > 
> > > Can you clarify if indeed you were using the full-blown multi-link
> > > mode with hardware synchronization or a regular single-link
> > > operation? I am not asking for details of your test hardware, just
> > > trying to reconstruct the program flow leading to this problem.
> > > 
> > 
> > Am testing on a regular single link, which hits this path.
> > 
> > > It could also be that your commit message was meant to say:
> > > "the msg lock is taken for multi-link cases only but released
> > > unconditionally, leading to an unlock balance warning for
> > > single-link usages"?
> > Yes.
> 
> Thanks for the precision. the change is legit so assuming the commit message
> is reworded to mention single link usage please feel free to take the
> following tag.
> 
> Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>
>

Changes looks okay to me. Please update commit message as pierre
suggested.

Acked-by: Sanyog Kale <sanyog.r.kale@...el.com>

> 
> Thanks!

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