[v2,01/12] drm/drv: Hold ref on parent device during drm_device lifetime

Commit Message

Noralf Trønnes Feb. 10, 2019, 1:10 p.m. UTC

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

Signed-off-by: Noralf Trønnes <[e-mail]>
---
 drivers/gpu/drm/drm_drv.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Patch

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index b04982101fcb..27017c15315a 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -496,7 +496,7 @@  int drm_dev_init(struct drm_device *dev,
 	BUG_ON(!parent);
 
 	kref_init(&dev->ref);
-	dev->dev = parent;
+	dev->dev = get_device(parent);
 	dev->driver = driver;
 
 	/* no per-device feature limits by default */
@@ -566,6 +566,7 @@  int drm_dev_init(struct drm_device *dev,
 	drm_minor_free(dev, DRM_MINOR_RENDER);
 	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->clientlist_mutex);
@@ -601,6 +602,8 @@  void drm_dev_fini(struct drm_device *dev)
 	drm_minor_free(dev, DRM_MINOR_PRIMARY);
 	drm_minor_free(dev, DRM_MINOR_RENDER);
 
+	put_device(dev->dev);
+
 	mutex_destroy(&dev->master_mutex);
 	mutex_destroy(&dev->ctxlist_mutex);
 	mutex_destroy(&dev->clientlist_mutex);