[PATCH 1/2] drm/virtio: fix virtio_gpu_execbuffer_ioctl locking

[PATCH 1/2] drm/virtio: fix virtio_gpu_execbuffer_ioctl locking

[Gerd Hoffmann]

Lockdep says we can't call vmemdup() while having objects reserved
because it needs the mmap semaphore.  So reorder the calls reserve
the objects later.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 drivers/gpu/drm/virtio/virtgpu_ioctl.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
index 205ec4abae2b..0477d1250f2d 100644
--- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
+++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
@@ -126,22 +126,22 @@ static int virtio_gpu_execbuffer_ioctl(struct drm_device *dev, void *data,
 		bo_handles = NULL;
 	}
 
-	if (buflist) {
-		ret = virtio_gpu_array_lock_resv(buflist);
-		if (ret)
-			goto out_unused_fd;
-	}
-
 	buf = vmemdup_user(u64_to_user_ptr(exbuf->command), exbuf->size);
 	if (IS_ERR(buf)) {
 		ret = PTR_ERR(buf);
-		goto out_unresv;
+		goto out_unused_fd;
+	}
+
+	if (buflist) {
+		ret = virtio_gpu_array_lock_resv(buflist);
+		if (ret)
+			goto out_memdup;
 	}
 
 	out_fence = virtio_gpu_fence_alloc(vgdev);
 	if(!out_fence) {
 		ret = -ENOMEM;
-		goto out_memdup;
+		goto out_unresv;
 	}
 
 	if (out_fence_fd >= 0) {
@@ -160,11 +160,11 @@ static int virtio_gpu_execbuffer_ioctl(struct drm_device *dev, void *data,
 			      vfpriv->ctx_id, buflist, out_fence);
 	return 0;
 
-out_memdup:
-	kvfree(buf);
 out_unresv:
 	if (buflist)
 		virtio_gpu_array_unlock_resv(buflist);
+out_memdup:
+	kvfree(buf);
 out_unused_fd:
 	kvfree(bo_handles);
 	if (buflist)
-- 
2.18.2

[PATCH 2/2] drm/virtio: fix virtio_gpu_cursor_plane_update().

[Gerd Hoffmann]

Add missing virtio_gpu_array_lock_resv() call.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 drivers/gpu/drm/virtio/virtgpu_plane.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c b/drivers/gpu/drm/virtio/virtgpu_plane.c
index ac42c84d2d7f..d1c3f5fbfee4 100644
--- a/drivers/gpu/drm/virtio/virtgpu_plane.c
+++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
@@ -260,6 +260,7 @@ static void virtio_gpu_cursor_plane_update(struct drm_plane *plane,
 		if (!objs)
 			return;
 		virtio_gpu_array_add_obj(objs, vgfb->base.obj[0]);
+		virtio_gpu_array_lock_resv(objs);
 		virtio_gpu_cmd_transfer_to_host_2d
 			(vgdev, 0,
 			 plane->state->crtc_w,
-- 
2.18.2