Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   David Laight <David.Laight@ACULAB.COM>
To:     'Andrew Lunn' <andrew@lunn.ch>, Brian Masney <bmasney@redhat.com>
CC:     "irusskikh@marvell.com" <irusskikh@marvell.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "edumazet@google.com" <edumazet@google.com>,
        "kuba@kernel.org" <kuba@kernel.org>,
        "pabeni@redhat.com" <pabeni@redhat.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "cth451@gmail.com" <cth451@gmail.com>
Subject: RE: [PATCH] net: atlantic: fix check for invalid ethernet addresses
Thread-Topic: [PATCH] net: atlantic: fix check for invalid ethernet addresses
Thread-Index: AQHZBQNlZXesXr8LFkOm0c8QYDoVsa5YF2cw
Date:   Wed, 30 Nov 2022 23:12:15 +0000
Message-ID: <3adb7dc622a3429782ca89e83c8e020d@AcuMS.aculab.com>
References: <20221130174259.1591567-1-bmasney@redhat.com>
 <Y4ex6WqiY8IdwfHe@lunn.ch> <Y4fGORYQRfYTabH1@x1> <Y4fMBl6sv+SUyt9Z@lunn.ch>
In-Reply-To: <Y4fMBl6sv+SUyt9Z@lunn.ch>
Accept-Language: en-GB, en-US
MIME-Version: 1.0
Content-Language: en-US
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8BIT
Precedence: bulk

From: Andrew Lunn
> Sent: 30 November 2022 21:33
...
> > That won't work for this board since that function only checks that the
> > MAC "is not 00:00:00:00:00:00, is not a multicast address, and is not
> > FF:FF:FF:FF:FF:FF." The MAC address that we get on all of our boards is
> > 00:17:b6:00:00:00.
> 
> Which is a valid MAC address. So i don't see why the kernel should
> reject it and use a random one.

It isn't very valid...
The first three bytes are the mulicast, local and company bits.
So the last three bytes being zero indicate you have the
very first address the company allocated.
Pretty much zero chance of that board ever working well
enough to be in a system.

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)