>From c37d436b8832e817ab437baa3324f6c08c846af9 Mon Sep 17 00:00:00 2001 From: Oliver Neukum <[email protected]> Date: Fri, 16 Jan 2015 15:13:28 +0100 Subject: [PATCH] cdc-wdm: bug in ceasing IO
The work submits the URB and the URB queues the work. To reliably kill this cycle a flag needs to be set and one of the kills repeated. Signed-off-by: Oliver Neukum <[email protected]> --- drivers/usb/class/cdc-wdm.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c index 5ff7018..e24bad6 100644 --- a/drivers/usb/class/cdc-wdm.c +++ b/drivers/usb/class/cdc-wdm.c @@ -976,8 +976,10 @@ static void wdm_disconnect(struct usb_interface *intf) wake_up_all(&desc->wait); mutex_lock(&desc->rlock); mutex_lock(&desc->wlock); + /* circular dependency. The second kill is needed */ kill_urbs(desc); cancel_work_sync(&desc->rxwork); + kill_urbs(desc); mutex_unlock(&desc->wlock); mutex_unlock(&desc->rlock); @@ -1017,9 +1019,10 @@ static int wdm_suspend(struct usb_interface *intf, pm_message_t message) set_bit(WDM_SUSPENDING, &desc->flags); spin_unlock_irq(&desc->iuspin); - /* callback submits work - order is essential */ + /* circular dependency. The second kill is needed */ kill_urbs(desc); cancel_work_sync(&desc->rxwork); + kill_urbs(desc); } if (!PMSG_IS_AUTO(message)) { mutex_unlock(&desc->wlock); @@ -1077,8 +1080,10 @@ static int wdm_pre_reset(struct usb_interface *intf) wake_up_all(&desc->wait); mutex_lock(&desc->rlock); mutex_lock(&desc->wlock); + /* circular dependency. The second kill is needed */ kill_urbs(desc); cancel_work_sync(&desc->rxwork); + kill_urbs(desc); return 0; } -- 1.8.4.5 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
