netdev - Re: [PATCH 1/2] net: phy: micrel: Add KS8851 PHY support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Sun, 3 Jan 2021 19:44:33 +0100
From:   Marek Vasut <marex@...x.de>
To:     Andrew Lunn <andrew@...n.ch>
Cc:     netdev@...r.kernel.org, Heiner Kallweit <hkallweit1@...il.com>,
        Lukas Wunner <lukas@...ner.de>
Subject: Re: [PATCH 1/2] net: phy: micrel: Add KS8851 PHY support

On 1/3/21 5:55 PM, Andrew Lunn wrote:
> On Sun, Jan 03, 2021 at 01:55:22PM +0100, Marek Vasut wrote:
>> On 12/30/20 4:43 PM, Andrew Lunn wrote:
>>> On Wed, Dec 30, 2020 at 01:53:57PM +0100, Marek Vasut wrote:
>>>> The KS8851 has a reduced internal PHY, which is accessible through its
>>>> registers at offset 0xe4. The PHY is compatible with KS886x PHY present
>>>> in Micrel switches, except the PHY ID Low/High registers are swapped.
>>>
>>> Can you intercept the reads in the KS8851 driver and swap them back
>>> again? The mv88e6xxx driver does something similar. The mv88e6393
>>> family of switches have PHYs with the Marvell OUI but no device ID. So
>>> the code traps these reads and provides an ID.
>>
>> I would prefer to keep this as-is, since then the PHY driver can match on
>> these swapped IDs and discern the PHY from PHY present in the KS886x switch.
> 
> The problem is, this ID contains an OUI. Well, part of an OUI, the top
> two bits of the OUI are removed, leaving 22 bits of a 24 bit
> OUI. These OUIs are assigned to companies, well organisations. If you
> look at the reversed PHY ID, what are the 4 possible OUIs? Who are
> they assigned to? Are they ever likely to manufacture a PHY?

Are these OUIs used for anything else than identifying the PHY though ?