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Date: Fri, 24 Aug 2001 17:38:05 -0400
From: Pete Zaitcev <zaitcev@redhat.com>
Message-Id: <200108242138.f7OLc5D12711@devserv.devel.redhat.com>
To: Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: PROBLEM: usb not working with 2.4.8-ac8
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> What was you test scenario where you didn't see a completion callback?

The root hub emulation never posts one.

> > +	if (ret == 0) {				/* N.B. Done, must notify */
> > +		/* uhci_call_completion(urb); */ /* ->> uhci_destroy_urb_priv */
> > +		urb->dev = NULL;
> > +		if (urb->complete)
> > +			urb->complete(urb);
> > +	}
> >  
> > -	usb_dec_dev_use(urb->dev);
> > +	usb_dec_dev_use(dev);

> What's all of this for? Protecting against an urb->dev race condition?

No race, but we cannot use urb after callback.

-- Pete