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Date: Thu, 6 Jun 2024 11:39:25 -0700
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Subject: Re: [PATCH] igb: Add MII write support
To: Andrew Lunn <andrew@lunn.ch>
CC: <jackie.jone@alliedtelesis.co.nz>, <davem@davemloft.net>,
	<jesse.brandeburg@intel.com>, <anthony.l.nguyen@intel.com>,
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References: <20240604031020.2313175-1-jackie.jone@alliedtelesis.co.nz>
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From: Jacob Keller <jacob.e.keller@intel.com>
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On 6/6/2024 11:31 AM, Andrew Lunn wrote:
>> Yea, its extremely easy to break things if you don't know what you're
>> doing here. So its more a question of "are we ok exposing yet another
>> way root can brick things?"
> 
> Many MAC drivers allow it, and we have not had complaints. It is not
> really something i'm a fan of, it in theory allows user space drivers
> for PHYs, but it is full of race conditions so in practice unlikely to
> work reliably.
> 
> If you are worried about it causing additional support issues because
> it gets abused, you could make it taint the kernel. That makes it
> clear all bets are off if used. For the use case presented here, a
> tainted kernel does not matter, it for lab testing, not production.
> 
>       Andrew
> 

This might be a good compromise. I don't feel too strong either way
regarding tainting the kernel. Adding support here I think will overall
be more helpful than harmful. I like the tainting idea as a way to help
reduce support burden and flag that something like this was done.

That being said, I don't think I personally have a problem with the
patch as-is given its intended use case so either way from me:

Acked-by: Jacob Keller <jacob.e.keller@intel.com>