USB: hub: change the locking in hub_activate

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>
This commit is contained in:
Alan Stern 2016-08-05 11:51:30 -04:00 committed by Greg Kroah-Hartman
parent ca5cbc8b02
commit 07d316a22e

View File

@ -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);