Re: [PATCH net-next v8 2/2] net: ethernet: Add driver for Sunplus SP7021

From: Andrew Lunn <andrew@lunn.ch>
To: Jakub Kicinski <kuba@kernel.org>
Cc: Wells Lu <wellslutw@gmail.com>,
	davem@davemloft.net, robh+dt@kernel.org, netdev@vger.kernel.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	p.zabel@pengutronix.de, pabeni@redhat.com, krzk+dt@kernel.org,
	roopa@nvidia.com, edumazet@google.com, wells.lu@sunplus.com
Subject: Re: [PATCH net-next v8 2/2] net: ethernet: Add driver for Sunplus SP7021
Date: Thu, 14 Apr 2022 15:36:41 +0200	[thread overview]
Message-ID: <Ylgjab6qLsrzKZKc@lunn.ch> (raw)
In-Reply-To: <20220414141825.50eb8b6a@kernel.org>

> > +		/* Get mac-address from nvmem. */
> > +		ret = spl2sw_nvmem_get_mac_address(&pdev->dev, port_np, mac_addr);
> > +		if (ret) {
> > +			dev_info(&pdev->dev, "Generate a random mac address!\n");
> > +
> > +			/* Generate a mac address using OUI of Sunplus Technology
> > +			 * and random controller number.
> > +			 */
> > +			mac_addr[0] = 0xfc; /* OUI of Sunplus: fc:4b:bc */
> > +			mac_addr[1] = 0x4b;
> > +			mac_addr[2] = 0xbc;
> > +			mac_addr[3] = get_random_int() % 256;
> > +			mac_addr[4] = get_random_int() % 256;
> > +			mac_addr[5] = get_random_int() % 256;
> 
> I don't think you can do that. Either you use your OUI and assign the
> address at manufacture or you must use a locally administered address.
> And if locally administered address is used it better be completely
> random to lower the probability of collision to absolute minimum.

I commented about that in an earlier version of these patches. We
probably need a quote from the 802.1 or 802.3 which says this is O.K.

	 Andrew