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	Sun, 10 Oct 2010 04:16:47 -0400
Subject: Re: phyX enumeration conflict
From: Johannes Berg <johannes@sipsolutions.net>
To: Christian Lamparter <chunkeey@googlemail.com>
Cc: linux-wireless <linux-wireless@vger.kernel.org>,
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Date: Sun, 10 Oct 2010 10:16:44 +0200
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On Sun, 2010-10-10 at 10:09 +0200, Johannes Berg wrote:

> The commit failed to take into account that allocated wireless devices
> (wiphys) are not added into the device list upon allocation, but only
> when they are registered. Therefore, it opened up a race between
> allocating and registering a name, so that if two processes allocate and
> register concurrently ("alloc, alloc, register, register" rather than
> "alloc, register, alloc, register") the code will attempt to use the
> same name twice.

And as for the actual feature, as far as I'm concerned the discussion
ends here because we otherwise need to use something as complex as idr.
A udev rule can't break the kernel and works just as well, even if
you'll have to use a different namespace, i.e. not "phy%d" -- use say
"wiphy%d" instead.

johannes