Re: [PATCH v1] drm/virtio: Fix driver removal with disabled KMS

[Dmitry Osipenko <dmitry.osipenko@collabora.com>]

Hi,

On 6/7/26 07:31, Ryosuke Yasuoka wrote:
> Hi Dmitry
> 
> On 04/06/2026 15:27, Dmitry Osipenko wrote:
>> DRM atomic and modesetting aren't initialized if virtio-gpu driver built
>> with disabled KMS, leading to access of uninitialized data on driver
>> removal/unbinding and crashing kernel. Fix it by skipping shutting down
>> atomic core with unavailable KMS.
>>
>> Fixes: 72122c69d717 ("drm/virtio: Add option to disable KMS support")
>> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
>> ---
>>  drivers/gpu/drm/virtio/virtgpu_drv.c | 5 ++++-
>>  1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.c b/drivers/gpu/drm/virtio/virtgpu_drv.c
>> index f0fb784c0f6f..2aaa7cb08085 100644
>> --- a/drivers/gpu/drm/virtio/virtgpu_drv.c
>> +++ b/drivers/gpu/drm/virtio/virtgpu_drv.c
>> @@ -138,7 +138,10 @@ static void virtio_gpu_remove(struct virtio_device *vdev)
>>  
>>  	virtio_gpu_release_vqs(dev);
>>  	drm_dev_unplug(dev);
>> -	drm_atomic_helper_shutdown(dev);
>> +
>> +	if (drm_core_check_feature(dev, DRIVER_ATOMIC))
>> +		drm_atomic_helper_shutdown(dev);
>> +
>>  	virtio_gpu_deinit(dev);
>>  	drm_dev_put(dev);
>>  }
> 
> The patch looks good to me at a glance. I haven't done a full, deep code
> review yet, but I've tested it on my lab and everything works as
> expected.
> 
> Tested-by: Ryosuke Yasuoka <ryasuoka@redhat.com>

Thanks a lot for the testing. The review from you will be very welcomed
too.

-- 
Best regards,
Dmitry