From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Berg <johannes@sipsolutions.net>
Subject: Re: [RFC][PATCH] Fix another namespace issue with devices assigned
 to  classes
Date: Tue, 08 Jun 2010 16:26:14 +0200
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Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
	Greg KH <greg@kroah.com>, netdev <netdev@vger.kernel.org>
To: Kay Sievers <kay.sievers@vrfy.org>
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On Tue, 2010-06-08 at 16:21 +0200, Kay Sievers wrote:

> > Well they will be unregistered and everything, but once all the netdevs
> > are gone etc. the devices you create in the patch might stick around
> > because somebody has them open in sysfs, and I see nothing that would
> > pin the module in that case?
> 
> That's what I mean, I have no idea how to solve that with network
> devices. I don't think any other subsytem allows to unload the module,
> when devices, the module has created, are in use.

You're right ... the would only be unregistered from your release, which
would happen after the module is long gone ...

> The current code uses the in-core class_create() logic, which was only
> meant for devices with a device node, and which is cleaned up by the
> core itself. That's why this issue never appeared before.
> 
> But as said, I have no idea how to solve that with a single module. It
> might not work at all without moving stuff into the core. That people
> use device_create() with no major/minor might indicate that something
> else is needed here. :)

So ... can we apply Eric's patch for now then?

johannes