[Intel-gfx] [PATCH 02/51] drm/i915: Don't clear drvdata in ->release

[Jani Nikula]

On Mon, 23 Mar 2020, Daniel Vetter <daniel.vetter at ffwll.ch> wrote:
> For two reasons:
>
> - The driver core clears this already for us after we're unloaded in
>   __device_release_driver().
>
> - It's way too late, the drm_device ->release callback might massively
>   outlive the underlying physical device, since a drm_device can't be

*can be*?

>   kept alive by open drm_file or well really anything else userspace
>   is still hanging onto. So if we clear this ourselves, we should
>   clear it in the pci ->remove callback, not in the drm_device
>   ->relase callback.

->release

Reviewed-by: Jani Nikula <jani.nikula at intel.com>

>
> Looking at git history this was fixed in the driver core with
>
> commit 0998d0631001288a5974afc0b2a5f568bcdecb4d
> Author: Hans de Goede <hdegoede at redhat.com>
> Date:   Wed May 23 00:09:34 2012 +0200
>
>     device-core: Ensure drvdata = NULL when no driver is bound
>
> v2: Cite the core fix in the commit message (Chris).
>
> Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.c | 3 ---
>  1 file changed, 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index 48ba37e35bea..4792051e9e2e 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -909,9 +909,6 @@ static void i915_driver_destroy(struct drm_i915_private *i915)
>  
>  	drm_dev_fini(&i915->drm);
>  	kfree(i915);
> -
> -	/* And make sure we never chase our dangling pointer from pci_dev */
> -	pci_set_drvdata(pdev, NULL);
>  }
>  
>  /**

-- 
Jani Nikula, Intel Open Source Graphics Center