From mboxrd@z Thu Jan  1 00:00:00 1970
From: Oliver Neukum <oliver@neukum.org>
Subject: Re: [PATCH 1/2 v5] usbnet: allow status interrupt URB to always be active
Date: Thu, 11 Apr 2013 14:28:43 +0200
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Cc: Dan Williams <dcbw@redhat.com>,
	Elina Pasheva <epasheva@sierrawireless.com>,
	Network Development <netdev@vger.kernel.org>,
	linux-usb <linux-usb@vger.kernel.org>,
	Rory Filer <rfiler@sierrawireless.com>,
	Phil Sutter <phil@nwl.cc>
To: Ming Lei <tom.leiming@gmail.com>
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On Thursday 11 April 2013 20:11:13 Ming Lei wrote:
> On Thu, Apr 11, 2013 at 7:14 PM, Oliver Neukum <oliver@neukum.org> wrote:
> >
> > Sorry, I misunderstood.
> 
> No problem, :-)
> 
> >
> > Task A                                  Task B                          queue
> >
> > queue work
> >                                                 request a reset
> >                                                                                         allocate memory and block
> >                                                 cancel the work
> >                                                                                         shit happened
> 
> If I understand the case correctly, the above deadlock can be avoided
> by canceling rx/tx URBs at the end of pre_reset() or usbnet_disconnect(),

No. cancel_work_sync() must wait for the work. The work will not finish.

	Regards
		Oliver