[PATCH]i915: use WARN_ON_ONCE in intel_dp_aux_transfer

[Dave Young]

On 12/01/16 at 04:00pm, Dave Young wrote:
> On 11/30/16 at 03:25pm, Ville Syrjälä wrote:
> > On Thu, Nov 24, 2016 at 05:03:20PM +0800, Dave Young wrote:
> > > On 11/24/16 at 10:53am, Jani Nikula wrote:
> > > > On Thu, 24 Nov 2016, Dave Young <dyoung at redhat.com> wrote:
> > > > > I see a lot of below warning:
> > > > 
> > > > No, we must not hide this under the carpet. There's a bug at fdo about
> > > > this, and we need to fix it.
> > > 
> > > It is not hiding it, just not repeating the warnings. But anyway I do
> > > not have strong opinion. I'm building my kernel with this patch until
> > > there is a real fix in upstream.
> > 
> > We already have a patch to reduce it a single WARN:
> > d4cb3fd9b548 ("drm/i915/dp: add lane_count check in intel_dp_check_link_status")
> 
> It works for me, thanks
> 
> > 
> > Do we need to get that backported to stable?
> 
> Personally I think it should but I'm not sure the policy of stable for i915 though.
> 

Hmm, I can not recall when I had such issue in which version of kernel
because I just pull and rebuild very often, so I should say I have no
idea .. 

> Thanks
> Dave