drm/virtio: Unlock reservations on dma_resv_reserve_fences() error

Unlock reservations on dma_resv_reserve_fences() error to fix recursive
locking of the reservations when this error happens.

Cc: stable@vger.kernel.org
Fixes: c8d4c18b ("dma-buf/drivers: make reserving a shared slot mandatory v4")
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220630200726.1884320-5-dmitry.osipenko@collabora.comSigned-off-by: Gerd Hoffmann <kraxel@redhat.com>

drivers/gpu/drm/virtio/virtgpu_gem.c

@@ -228,8 +228,10 @@ int virtio_gpu_array_lock_resv(struct virtio_gpu_object_array *objs)
 
 	for (i = 0; i < objs->nents; ++i) {
 		ret = dma_resv_reserve_fences(objs->objs[i]->resv, 1);
-		if (ret)
+		if (ret) {
+			virtio_gpu_array_unlock_resv(objs);
 			return ret;
+		}
 	}
 	return ret;
 }