From: Rafael J. Wysocki rafael.j.wysocki@intel.com
commit 9226c504e364158a17a68ff1fe9d67d266922f50 upstream.
Since the device is resumed from runtime-suspend in __device_release_driver() anyway, it is better to do that before looking for busy managed device links from it to consumers, because if there are any, device_links_unbind_consumers() will be called and it will cause the consumer devices' drivers to unbind, so the consumer devices will be runtime-resumed. In turn, resuming each consumer device will cause the supplier to be resumed and when the runtime PM references from the given consumer to it are dropped, it may be suspended. Then, the runtime-resume of the next consumer will cause the supplier to resume again and so on.
Update the code accordingly.
Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Fixes: 9ed9895370ae ("driver core: Functional dependencies tracking support") Cc: All applicable stable@vger.kernel.org # All applicable Tested-by: Xiang Chen chenxiang66@hisilicon.com Reviewed-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/base/dd.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
--- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -816,6 +816,8 @@ static void __device_release_driver(stru
drv = dev->driver; if (drv) { + pm_runtime_get_sync(dev); + while (device_links_busy(dev)) { device_unlock(dev); if (parent) @@ -831,11 +833,12 @@ static void __device_release_driver(stru * have released the driver successfully while this one * was waiting, so check for that. */ - if (dev->driver != drv) + if (dev->driver != drv) { + pm_runtime_put(dev); return; + } }
- pm_runtime_get_sync(dev); pm_runtime_clean_up_links(dev);
driver_sysfs_remove(dev);