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From: Doug Rabson <dfr@nlsystems.com>
To: Dag-Erling =?ISO-8859-1?Q?Sm=F8rgrav?= <des@des.no>
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cc: arch@freebsd.org
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Subject: Re: newbus flaw
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On Thu, 2004-05-13 at 11:46, Dag-Erling Smørgrav wrote:
> Doug Rabson <dfr@nlsystems.com> writes:
> > When the old module unloaded, its driver will have detached from the 
> > device which it created. There is no reference to an old driver_t. Its 
> > perfectly safe for the new driver to use the old device.
> 
> so why do you say I "shouldn't reset the old driver and desc"?

I didn't say that (that was John-Mark). When you create a device using
something like device_add_child(parent, "foo", unit), the new device is
just labelled as a 'fooN' - it has no reference to any 'foo' driver and
should have since there may be several. The 'foo'ness of the device is
used to match the device against a suitable driver at probe time.