[PATCH 4.4 039/113] USB: hub: change the locking in hub_activate
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2016-09-05 16:51:13
Also in:
lkml
4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alan Stern <stern@rowland.harvard.edu> commit 07d316a22e119fa301fd7dba7f1e1adfd4f72c05 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/usb/core/hub.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c@@ -1036,7 +1036,7 @@ static void hub_activate(struct usb_hub /* 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)
@@ -1243,7 +1243,7 @@ static void hub_activate(struct usb_hub 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);
@@ -1266,7 +1266,7 @@ static void hub_activate(struct usb_hub /* 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);