driver core: Add missing dev->bus->need_parent_lock checks

__device_release_driver() has to check dev->bus->need_parent_lock
before dropping the parent lock and acquiring it again as it may
attempt to drop a lock that hasn't been acquired or lock a device
that shouldn't be locked and create a lock imbalance.

Fixes: 8c97a46af0 (driver core: hold dev's parent lock when needed)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Rafael J. Wysocki 2018-12-13 19:27:47 +01:00 committed by Greg Kroah-Hartman
parent df44b47965
commit e121a83374
1 changed files with 2 additions and 2 deletions

View File

@ -933,11 +933,11 @@ static void __device_release_driver(struct device *dev, struct device *parent)
if (drv) {
while (device_links_busy(dev)) {
device_unlock(dev);
if (parent)
if (parent && dev->bus->need_parent_lock)
device_unlock(parent);
device_links_unbind_consumers(dev);
if (parent)
if (parent && dev->bus->need_parent_lock)
device_lock(parent);
device_lock(dev);