[Intel-gfx] [PATCH 4/4] drm/i915: Fix oops on platforms w/o hpd support

[Ville Syrjälä]

On Thu, Oct 14, 2021 at 12:20:24PM +0300, Jani Nikula wrote:
> On Thu, 14 Oct 2021, Jani Nikula <jani.nikula at intel.com> wrote:
> > On Thu, 14 Oct 2021, Ville Syrjala <ville.syrjala at linux.intel.com> wrote:
> >> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >>
> >> We don't have hpd support on i8xx/i915 which means hotplug_funcs==NULL.
> >> Let's not oops when loading the driver on one those machines.
> >
> > D'oh!
> >
> > Lemme guess, CI just casually dropped the machines from the results
> > because they didn't boot?
> >
> > Reviewed-by: Jani Nikula <jani.nikula at intel.com>
> >
> >>
> >> Cc: Dave Airlie <airlied at redhat.com>
> >> Cc: Jani Nikula <jani.nikula at intel.com>
> >> Fixes: cd030c7c11a4 ("drm/i915: constify hotplug function vtable.")
> >> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >> ---
> >>  drivers/gpu/drm/i915/display/intel_hotplug.c | 3 ++-
> >>  1 file changed, 2 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/gpu/drm/i915/display/intel_hotplug.c b/drivers/gpu/drm/i915/display/intel_hotplug.c
> >> index 3c1cec953b42..0e949a258a22 100644
> >> --- a/drivers/gpu/drm/i915/display/intel_hotplug.c
> >> +++ b/drivers/gpu/drm/i915/display/intel_hotplug.c
> >> @@ -215,7 +215,8 @@ intel_hpd_irq_storm_switch_to_polling(struct drm_i915_private *dev_priv)
> >>  
> >>  static void intel_hpd_irq_setup(struct drm_i915_private *i915)
> >>  {
> >> -	if (i915->display_irqs_enabled && i915->hotplug_funcs->hpd_irq_setup)
> >> +	if (i915->display_irqs_enabled &&
> >> +	    i915->hotplug_funcs && i915->hotplug_funcs->hpd_irq_setup)
> 
> Btw i915->hotplug_funcs->hpd_irq_setup is always set if
> i915->hotplug_funcs is set, so that bit is a bit redundant.

Right. I'll drop the drop the belt, leaving just the suspenders.

> 
> Anyway, r-b stands either way you decide to go.
> 
> 
> >>  		i915->hotplug_funcs->hpd_irq_setup(i915);
> >>  }
> 
> -- 
> Jani Nikula, Intel Open Source Graphics Center

-- 
Ville Syrjälä
Intel