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From: Duncan Sands <baldrick@free.fr>
To: Greg KH <greg@kroah.com>
Subject: Re: [linux-usb-devel] Re: [OOPS,  usbcore, releaseintf] 2.6.0-test10-mm1
Date: Thu, 11 Dec 2003 09:49:54 +0100
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Cc: Alan Stern <stern@rowland.harvard.edu>,
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       USB development list <linux-usb-devel@lists.sourceforge.net>
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> > I don't know if you've been following this thread or not, but the oops
> > occurred when I modified usbfs to hold a reference to the usb_device
> > until no-one was using a given usbfs file.
>
> That's a good thing to do.  It should work.
>
> > I guess this means that I should change my patch so that the reference
> > to the usb_device is dropped as soon as possible, right?
>
> No, the bug should be fixed.  I've seen this bug happen if someone has a
> usb-serial device open and then unload the host controller driver.  In
> fact, I think there's a bugzilla entry just for that...

Hi Greg, what I meant was: should I make my patch friendlier to rmmod by
trying hard to drop the reference as soon as possible, though some code paths
may have to hold on to it for a long time (cost: code complication), or is it OK
to always hang onto the usb_device as long as one of the usbfs files is open
(cost: rmmod may take a long or infinite time; advantages: simple, robust)?
This lowly one humbly awaits enlightenment... :)

Thanks,

Duncan.