[Intel-gfx] [RFC PATCH] drm/i915: Restore full symmetry in i915_driver_modeset_probe/remove

[Jani Nikula]

On Mon, 21 Oct 2019, Jani Nikula <jani.nikula at intel.com> wrote:
> On Mon, 21 Oct 2019, Jani Nikula <jani.nikula at intel.com> wrote:
>> On Fri, 18 Oct 2019, Janusz Krzysztofik <janusz.krzysztofik at linux.intel.com> wrote:
>>> Commit 2d6f6f359fd8 ("drm/i915: add i915_driver_modeset_remove()")
>>
>> Please look at that commit and explain to me how it impacts anything
>> about intel_irq_uninstall().
>
> Seriously, why was this merged already? It does not fix *anything*. It
> cites a commit that does not break anything.

And for crying out loud, merged without passing CI results.


>
> You're calling intel_irq_uninstall() *twice* for no good reason.
>
> The whole probe/remove callchains are a mess, and I'm in the process of
> cleaning it up properly. What good does this patch bring for the overall
> effort, other than another useless quirk in the call chain to take into
> account? Indeed, the only actual functional change it makes in the
> remove path is not mentioned in the commit message at all!
>
>
> BR,
> Jani.
>
>
>>
>> BR,
>> Jani.
>>
>>
>>> claimed removal of asymmetry in probe() and remove() calls, however, it
>>> didn't take care of calling intel_irq_uninstall() on driver remove.
>>> That doesn't hurt as long as we still call it from
>>> intel_modeset_driver_remove() but in order to have full symmetry we
>>> should call it again from i915_driver_modeset_remove().
>>>
>>> Note that it's safe to call intel_irq_uninstall() twice thanks to
>>> commit b318b82455bd ("drm/i915: Nuke drm_driver irq vfuncs").  We may
>>> only want to mention the case we are adding in a related FIXME comment
>>> provided by that commit.  While being at it, update the name of
>>> function mentioned as calling it out of sequence as that name has been
>>> changed meanwhile by commit 78dae1ac35dd ("drm/i915: Propagate
>>> "_remove" function name suffix down").
>>>
>>> Suggested-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
>>> Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik at linux.intel.com>
>>> Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
>>> ---
>>>  drivers/gpu/drm/i915/i915_drv.c | 2 ++
>>>  drivers/gpu/drm/i915/i915_irq.c | 8 ++++----
>>>  2 files changed, 6 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
>>> index dd9613e45723..4ae9bfa96290 100644
>>> --- a/drivers/gpu/drm/i915/i915_drv.c
>>> +++ b/drivers/gpu/drm/i915/i915_drv.c
>>> @@ -452,6 +452,8 @@ static void i915_driver_modeset_remove(struct drm_i915_private *i915)
>>>  
>>>  	intel_modeset_driver_remove(i915);
>>>  
>>> +	intel_irq_uninstall(i915);
>>> +
>>>  	intel_bios_driver_remove(i915);
>>>  
>>>  	vga_switcheroo_unregister_client(pdev);
>>> diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
>>> index bc83f094065a..0160283860a6 100644
>>> --- a/drivers/gpu/drm/i915/i915_irq.c
>>> +++ b/drivers/gpu/drm/i915/i915_irq.c
>>> @@ -4515,10 +4515,10 @@ void intel_irq_uninstall(struct drm_i915_private *dev_priv)
>>>  	int irq = dev_priv->drm.pdev->irq;
>>>  
>>>  	/*
>>> -	 * FIXME we can get called twice during driver load
>>> -	 * error handling due to intel_modeset_cleanup()
>>> -	 * calling us out of sequence. Would be nice if
>>> -	 * it didn't do that...
>>> +	 * FIXME we can get called twice during driver probe
>>> +	 * error handling as well as during driver remove due to
>>> +	 * intel_modeset_driver_remove() calling us out of sequence.
>>> +	 * Would be nice if it didn't do that...
>>>  	 */
>>>  	if (!dev_priv->drm.irq_enabled)
>>>  		return;

-- 
Jani Nikula, Intel Open Source Graphics Center