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 17:06:30 +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 16:47 +0200, Kay Sievers wrote:

> > So ... can we apply Eric's patch for now then?
> 
> It might break other stuff we don't know about yet. Just like we did
> not know about what things hwsim is doing here. :)

True.

> The hwsim issues are caused by the current hwsim code, by doing things
> it should not do. Class devices of different classes must never be
> stacked (the core should not allow that in the first place). Class
> devices must never have a driver assigned behind its back. Also
> device_create() should not be used for devices without a major/minor
> (but that seems to be done in several other places too).

Back when hwsim was written that would have been useful feedback to
whoever did ... now, not so much.

> To fix the hwsim driver core interaction, core changes will probably
> be needed to allow network modules to be removed while their devices
> are active. That's something which seems not to work for bus devices
> currently.

Well it just needs to pin the module refcount from the bus and/or device
struct. That seems not too hard?

johannes