drm/drv: Hold ref on parent device during drm_device lifetime

[ Upstream commit 56be6503aab2bc3a30beae408071b9be5e1bae51 ]

This makes it safe to access drm_device->dev after the parent device has
been removed/unplugged.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190225144232.20761-2-noralf@tronnes.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Noralf Trønnes 2019-02-25 15:42:26 +01:00 committed by Greg Kroah-Hartman
parent 3e04442636
commit b2a21fe258

View File

@ -505,7 +505,7 @@ int drm_dev_init(struct drm_device *dev,
}
kref_init(&dev->ref);
dev->dev = parent;
dev->dev = get_device(parent);
dev->driver = driver;
INIT_LIST_HEAD(&dev->filelist);
@ -572,6 +572,7 @@ err_minors:
drm_minor_free(dev, DRM_MINOR_CONTROL);
drm_fs_inode_free(dev->anon_inode);
err_free:
put_device(dev->dev);
mutex_destroy(&dev->master_mutex);
mutex_destroy(&dev->ctxlist_mutex);
mutex_destroy(&dev->filelist_mutex);
@ -607,6 +608,8 @@ void drm_dev_fini(struct drm_device *dev)
drm_minor_free(dev, DRM_MINOR_RENDER);
drm_minor_free(dev, DRM_MINOR_CONTROL);
put_device(dev->dev);
mutex_destroy(&dev->master_mutex);
mutex_destroy(&dev->ctxlist_mutex);
mutex_destroy(&dev->filelist_mutex);