Once a DRM device is unregistered, user-space must not access any existing mmaps, anymore. As we cannot rely on this, we now zap all of them in drm_dev_unregister(). Any driver which wants to support that needs to protect their fault() and mmap() handlers via drm_dev_get_active(), otherwise users can create new mmaps after/during drm_dev_unregister(). Signed-off-by: David Herrmann <dh.herrmann@xxxxxxxxx> --- drivers/gpu/drm/drm_stub.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c index e363b72..274a005 100644 --- a/drivers/gpu/drm/drm_stub.c +++ b/drivers/gpu/drm/drm_stub.c @@ -602,6 +602,10 @@ void drm_dev_unregister(struct drm_device *dev) drm_dev_shutdown(dev); + /* zap all memory mappings (drm_global_mutex must not be locked) */ + if (dev->dev_mapping) + unmap_mapping_range(dev->dev_mapping, 0, LLONG_MAX, 1); + /* We cannot hold drm_global_mutex during drm_dev_shutdown() as it might * dead-lock. Hence, there's a small race between drm_dev_shutdown() and * us locking drm_global_mutex which drm_release() might trigger. To fix -- 1.8.4.1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
