Subject: Re: device tree traversal
To: Garrett D'Amore <>
From: Daniel Carosone <>
List: tech-kern
Date: 07/04/2006 15:38:00
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On Mon, Jul 03, 2006 at 10:22:57PM -0700, Garrett D'Amore wrote:
> I am unaware of any buses besides pcmcia and USB/firewire which are
> designed to support hot detach without advance notification to the
> driver.  Indeed, even Cardbus doesn't support this properly -- a detach
> notification is required from userland _before_ physical removal in
> order to guarantee safe operation.

One possible fly in the ointment: there are usb-to-pci bridges (and
many other weird things besides), so you can have a pci bus behind a
hot-deteached usb device.  I've seen them get used for USB video cards
among other things.

Trying to deal with these might well lead to otherwise-unnecessary
overengineering, of course, but it's worth mentioning.


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