Commit 21eb93f4 authored by Saravana Kannan's avatar Saravana Kannan Committed by Greg Kroah-Hartman
Browse files

driver core: Call sync_state() even if supplier has no consumers 



The initial patch that added sync_state() support didn't handle the case
where a supplier has no consumers. This was because when a device is
successfully bound with a driver, only its suppliers were checked to see
if they are eligible to get a sync_state(). This is not sufficient for
devices that have no consumers but still need to do device state clean
up. So fix this.

Fixes: fc5a251d (driver core: Add sync_state driver/bus callback)
Signed-off-by: default avatarSaravana Kannan <saravanak@google.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200221080510.197337-2-saravanak@google.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent ae91c925

drivers/base/core.c

+17 −6
Original line number Diff line number Diff line
@@ -745,17 +745,22 @@ static void __device_links_queue_sync_state(struct device *dev, 
/**

 * device_links_flush_sync_list - Call sync_state() on a list of devices

 * @list: List of devices to call sync_state() on

 * @dont_lock_dev: Device for which lock is already held by the caller

 *

 * Calls sync_state() on all the devices that have been queued for it. This

 * function is used in conjunction with __device_links_queue_sync_state().

 * function is used in conjunction with __device_links_queue_sync_state(). The

 * @dont_lock_dev parameter is useful when this function is called from a

 * context where a device lock is already held.

 */

static void device_links_flush_sync_list(struct list_head *list)

static void device_links_flush_sync_list(struct list_head *list,

					 struct device *dont_lock_dev)

{

	struct device *dev, *tmp;



	list_for_each_entry_safe(dev, tmp, list, links.defer_sync) {

		list_del_init(&dev->links.defer_sync);



		if (dev != dont_lock_dev)

			device_lock(dev);



		if (dev->bus->sync_state)
@@ -763,6 +768,7 @@ static void device_links_flush_sync_list(struct list_head *list) 
		else if (dev->driver && dev->driver->sync_state)

			dev->driver->sync_state(dev);



		if (dev != dont_lock_dev)

			device_unlock(dev);



		put_device(dev);
@@ -801,7 +807,7 @@ void device_links_supplier_sync_state_resume(void) 
out:

	device_links_write_unlock();



	device_links_flush_sync_list(&sync_list);

	device_links_flush_sync_list(&sync_list, NULL);

}



static int sync_state_resume_initcall(void)
@@ -865,6 +871,11 @@ void device_links_driver_bound(struct device *dev) 
			driver_deferred_probe_add(link->consumer);

	}



	if (defer_sync_state_count)

		__device_links_supplier_defer_sync(dev);

	else

		__device_links_queue_sync_state(dev, &sync_list);



	list_for_each_entry(link, &dev->links.suppliers, c_node) {

		if (!(link->flags & DL_FLAG_MANAGED))

			continue;
@@ -883,7 +894,7 @@ void device_links_driver_bound(struct device *dev) 


	device_links_write_unlock();



	device_links_flush_sync_list(&sync_list);

	device_links_flush_sync_list(&sync_list, dev);

}



static void device_link_drop_managed(struct device_link *link)

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