On Mon, Jul 12, 2021 at 11:59:37PM +0200, Pavel Machek wrote:
Hi!
From: Xie Yongji <xieyongji@xxxxxxxxxxxxx>
[ Upstream commit 17f46f488a5d82c5568e6e786cd760bba1c2ee09 ]
The dev->dev_private might not be allocated if virtio_gpu_pci_quirk()
or virtio_gpu_init() failed. In this case, we should avoid the cleanup
in virtio_gpu_release().
The check is in wrong place at least in 4.4:
+++ b/drivers/gpu/drm/virtio/virtgpu_kms.c
@@ -257,6 +257,9 @@ int virtio_gpu_driver_unload(struct drm_device *dev)
flush_work(&vgdev->config_changed_work);
vgdev->vdev->config->del_vqs(vgdev->vdev);
+ if (!vgdev)
+ return;
+
Pointer is dereferenced before being tested.
Heh, yes, thanks for catching that. I'll drop it for now and rework it
next week.
--
Thanks,
Sasha
