From mboxrd@z Thu Jan  1 00:00:00 1970
From: ebiederm@xmission.com (Eric W. Biederman)
Subject: Re: [PATCH] Driver-core: Always create class directories fixing the  broken network drivers.
Date: Sun, 20 Jun 2010 05:29:02 -0700
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Cc: Johannes Berg <johannes@sipsolutions.net>,
	Greg KH <greg@kroah.com>, netdev <netdev@vger.kernel.org>
To: Kay Sievers <kay.sievers@vrfy.org>
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In-Reply-To: <AANLkTikZAKZA9mfb7RjaqNFnX8gCM3A9PTfH350botL8@mail.gmail.com> (Kay Sievers's message of "Sun\, 20 Jun 2010 13\:46\:20 +0200")
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Kay Sievers <kay.sievers@vrfy.org> writes:

> On Sun, Jun 20, 2010 at 13:33, Johannes Berg <johannes@sipsolutions.net> wrote:
>> On Sun, 2010-06-20 at 12:52 +0200, Kay Sievers wrote:
>>
>>> As mentioned earlier, It's pretty fragile to change things in this
>>> area, and I prefer the broken network driver-core interactions to be
>>> fixed instead - even when they are more complicated.
>>
>> Can you _please_ offer a proper way to fix it then?
>
> Sorry, I have no real experience with the issues created by the
> assumption that network driver need to be able to get unloaded while
> in use. That's very special, always requires a
> compiled-into-the-kernel part of the subsystem, and makes it hard to
> work with, as we can not use any of the usual core infrastructure to
> solve that.

So please look at https://bugzilla.kernel.org/show_bug.cgi?id=16215

That simply creates and destroys the network device as things come
and go.

I think the bnep case is much more serious because it is real hardware
not a testing simulation, and it is the second instance of this.

Calling the change broken when I can boot up and run X in that
configuration just fine is a vast overstatement.  Especially
when you don't acknowledge that the device layer is broken.

I will agree that insane amounts of backwards compatibility are a good
idea.  So I will cook up a version of my patch that adds a hack to the
device layer to only apply this change to devices of class net.

That should save let us postpone the architectural dreams for another
day.

Eric