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Date:   Thu, 5 Aug 2021 21:28:22 +0200
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Dan Williams <dan.j.williams@intel.com>
Cc:     "Kuppuswamy, Sathyanarayanan" 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        Andi Kleen <ak@linux.intel.com>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux Doc Mailing List <linux-doc@vger.kernel.org>
Subject: Re: [PATCH v1] driver: base: Add driver filter support
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On Thu, Aug 05, 2021 at 12:18:12PM -0700, Dan Williams wrote:
> On Thu, Aug 5, 2021 at 12:12 PM Greg Kroah-Hartman
> <gregkh@linuxfoundation.org> wrote:
> >
> > On Thu, Aug 05, 2021 at 11:53:52AM -0700, Kuppuswamy, Sathyanarayanan wrote:
> > > I am not sure how USB and Thunderbolt "authorzied" model works. But I
> > > don't think it prevents built-in driver probes during kernel boot right?
> >
> > Yes it does.
> >
> > Again Intel created this framework well over a decade ago for busses
> > that it deemed that it did not want to "trust" to instantly probe
> > drivers for and made it part of the Wireless USB specification.
> >
> > Then Intel went and added the same framework to Thunderbolt for the same
> > reason.
> >
> > To ignore this work is quite odd, you might want to talk to your
> > coworkers...
> 
> Sometimes we need upstream to connect us wayward drones back into the
> hive mind. Forgive me for not immediately recognizing that the
> existing 'authorized' mechanisms might be repurposed for this use
> case.

Not your fault, I'm more amazed that Andi doesn't remember this, he's
been around longer :)

But the first instinct should not be "let's go add a new feature", but
rather, "how has this problem been solved by others first" because,
really, this is not a new issue at all.  You should not rely on just me
to point out existing kernel features, we do have documentation you
know...

thanks,

greg k-h