USB: hub: change the locking in hub_activate (07d316a2) · Commits · 戴 / test

The locking in hub_activate() is not adequate to provide full mutual exclusion with hub_quiesce(). The subroutine locks the hub's usb_interface, but the callers of hub_quiesce() (such as hub_pre_reset() and hub_event()) hold the lock to the hub's usb_device. This patch changes hub_activate() to make it acquire the same lock as those other routines. Signed-off-by:

Alan Stern <stern@rowland.harvard.edu> CC: <stable@vger.kernel.org> #4.4+ Signed-off-by:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/hub.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -1052,7 +1052,7 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)

		/* Continue a partial initialization */
		if (type == HUB_INIT2 \|\| type == HUB_INIT3) {
		device_lock(hub->intfdev);
		device_lock(&hdev->dev);

		/* Was the hub disconnected while we were waiting? */
		if (hub->disconnected)
		@@ -1259,7 +1259,7 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
		queue_delayed_work(system_power_efficient_wq,
		&hub->init_work,
		msecs_to_jiffies(delay));
		device_unlock(hub->intfdev);
		device_unlock(&hdev->dev);
		return; /* Continues at init3: below */
		} else {
		msleep(delay);
		@@ -1282,7 +1282,7 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
		/* Allow autosuspend if it was suppressed */
		disconnected:
		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
		device_unlock(hub->intfdev);
		device_unlock(&hdev->dev);
		}

		kref_put(&hub->kref, hub_release);

Admin message