On Tue, 27 Apr 2004, Greg KH wrote:

> So, what's next in this patch series?  :)

Funny you should ask...

While writing those patches I noted a problem, that the USB device tree
can change while a process reading /proc/bus/usb/devices is traversing it,
leading to an oops when a pointer to a no-longer-existing child device is
dereferenced.  The ensuing discussion led to the conclusion that the
devices' ->serialize locks should be acquired, top-down, while going
through the tree.

That means changing the code that populates the devices file and changing
the code that adds and removes USB device structures.  This patch takes
care of the first part.  I'm delaying the second part because that section
of usbcore is still under change -- David Brownell's revisions have not
yet been fully integrated.

A similar change should be made to usb_find_device() and match_device() in
usb.c.  You may want to add that yourself.