This is a note to let you know that I've just added the patch titled
driver core: Add missing dev->bus->need_parent_lock checks
to my driver-core git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git in the driver-core-testing branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will be merged to the driver-core-next branch sometime soon, after it passes testing, and the merge window is open.
If you have any questions about this process, please let me know.
From e121a833745b4708b660e3fe6776129c2956b041 Mon Sep 17 00:00:00 2001
From: "Rafael J. Wysocki" rafael.j.wysocki@intel.com Date: Thu, 13 Dec 2018 19:27:47 +0100 Subject: 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: 8c97a46af04b (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 --- 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 88713f182086..8ac10af17c00 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -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);