Commit e121a833 authored Dec 13, 2018 by Rafael J. Wysocki Committed by Greg Kroah-Hartman Dec 19, 2018

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: 8c97a46a (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>

parent df44b479

drivers/base/dd.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -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);

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