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Subject: Re: pull-request: wireless-drivers-next-2020-12-03
To:     Jakub Kicinski <kuba@kernel.org>,
        Brian Norris <briannorris@chromium.org>
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From:   Edward Cree <ecree.xilinx@gmail.com>
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Date:   Tue, 8 Dec 2020 15:01:39 +0000
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On 07/12/2020 20:10, Jakub Kicinski wrote:
> On Mon, 7 Dec 2020 11:35:53 -0800 Brian Norris wrote:
>> Is there some reference for this rule (e.g., dictate from on high; or
>> some explanation of reasons)? Or limitations on it?
> 
> TBH its one of those "widely accepted truth" in networking which was
> probably discussed before I started compiling kernels so I don't know
> the full background.

My understanding is that it's because users can have them in their
 modprobe.conf, which causes breakage if an update removes the param.
 I think the module insert fails if there are unrecognised parameters
 there.

>> this sounds like one could never drop a module parameter, or remove
>> obsolete features.
Not far from the truth.  If you stop the network from coming up on
 boot you can really ruin a sysadmin's day :-/
But usually you can remove the feature, and leave the modparam not
 connected to anything, except maybe a deprecation warning printk if
 it's set to something other than the default.

-ed