usb: don't use PREPARE_DELAYED_WORK (77fa83cf) · Commits · 戴 / test

PREPARE_[DELAYED_]WORK() are being phased out. They have few users and a nasty surprise in terms of reentrancy guarantee as workqueue considers work items to be different if they don't have the same work function. usb_hub->init_work is multiplexed with multiple work functions; however, the work item is never queued while in-flight, so we can simply use INIT_DELAYED_WORK() before each queueing. It would probably be best to route this with other related updates through the workqueue tree. Lightly tested. v2: Greg and Alan confirm that the work item is never queued while in-flight. Simply use INIT_DELAYED_WORK(). Signed-off-by:

Tejun Heo <tj@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: linux-usb@vger.kernel.org

drivers/usb/core/hub.c

+2 −2

Original line number	Original line	Diff line number	Diff line
	@@ -1040,7 +1040,7 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
	*/		*/
	if (type == HUB_INIT) {		if (type == HUB_INIT) {
	delay = hub_power_on(hub, false);		delay = hub_power_on(hub, false);
	PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);		INIT_DELAYED_WORK(&hub->init_work, hub_init_func2);
	schedule_delayed_work(&hub->init_work,		schedule_delayed_work(&hub->init_work,
	msecs_to_jiffies(delay));		msecs_to_jiffies(delay));

	@@ -1194,7 +1194,7 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)

	/* Don't do a long sleep inside a workqueue routine */		/* Don't do a long sleep inside a workqueue routine */
	if (type == HUB_INIT2) {		if (type == HUB_INIT2) {
	PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);		INIT_DELAYED_WORK(&hub->init_work, hub_init_func3);
	schedule_delayed_work(&hub->init_work,		schedule_delayed_work(&hub->init_work,
	msecs_to_jiffies(delay));		msecs_to_jiffies(delay));
	return; /* Continues at init3: below */		return; /* Continues at init3: below */

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