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

[Jani Nikula]

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.

Anyway, r-b stands either way you decide to go.


>>  		i915->hotplug_funcs->hpd_irq_setup(i915);
>>  }

-- 
Jani Nikula, Intel Open Source Graphics Center