From 5781b53dd89c1034daa0929fe98f87f87d1af914 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 13 Dec 2018 19:27:47 +0100 Subject: [PATCH] driver core: Add missing dev->bus->need_parent_lock checks commit e121a833745b4708b660e3fe6776129c2956b041 upstream. __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: 8c97a46af04b (driver core: hold dev's parent lock when needed) Signed-off-by: Rafael J. Wysocki Cc: stable Reviewed-by: Daniel Vetter Signed-off-by: Greg Kroah-Hartman --- drivers/base/dd.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/base/dd.c b/drivers/base/dd.c index edfc9f0..2607f85 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -931,11 +931,11 @@ static void __device_release_driver(struct device *dev, struct device *parent) 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); -- 2.7.4