[Intel-gfx] [PATCH v2] drm/i915: Fix lock dropping in intel_tv_detect()

[Chris Wilson]

On Tue, Sep 02, 2014 at 11:16:12AM +0300, Ville Syrjälä wrote:
> On Tue, Sep 02, 2014 at 10:41:05AM +0300, Jani Nikula wrote:
> > On Mon, 01 Sep 2014, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> > > On Mon, Sep 01, 2014 at 01:36:37PM +0300, Ville Syrjälä wrote:
> > >> On Mon, Sep 01, 2014 at 11:20:09AM +0100, Chris Wilson wrote:
> > >> > On Mon, Sep 01, 2014 at 01:07:40PM +0300, ville.syrjala at linux.intel.com wrote:
> > >> > > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > >> > > 
> > >> > > When intel_tv_detect() fails to do load detection it would forget to
> > >> > > drop the locks and clean up the acquire context. Fix it up.
> > >> > > 
> > >> > > This is a regression from:
> > >> > >  commit 208bf9fdcd3575aa4a5d48b3e0295f7cdaf6fc44
> > >> > >  Author: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > >> > >  Date:   Mon Aug 11 13:15:35 2014 +0300
> > >> > > 
> > >> > >     drm/i915: Fix locking for intel_enable_pipe_a()
> > >> > > 
> > >> > > v2: Make the code more readable (Chris)
> > >> > > 
> > >> > > Cc: Tibor Billes <tbilles at gmx.com>
> > >> > > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > >> > 
> > >> > Hmm, if we use WARN_ON() you should init type.
> > >> 
> > >> type is always set in the branch that sets status=connected.
> > >
> > > Back to thinking about readability and making sure that the WARN_ON
> > > never happens with just a glance. Otherwise, the WARN_ON would be better
> > > as WARN_ON(unsigned)type >= last_tv_type); Or something. Anway, take
> > > your pick and slap my r-b on it. :)
> > 
> > Ville?
> 
> I don't know anymore. Just kill the WARN_ON() if it makes things
> confusing?

Just drop the WARN_ON. I prefer the if() using the status rather than
type, as that seems more idiomatic (when looking at our other detection
routines).
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre