This is an Alpha XL300 (ev5) machine and de2104x boots sometimes with a wrong mac address. Well the address is very very similar, it's just one byte shifted. It can start so: de2104x PCI Ethernet driver v0.7 (Mar 17, 2004) eth0: 21040 at 0xfffffc8602231000, 00:f8:22:00:ee:f1, IRQ 29 ... or so: de2104x PCI Ethernet driver v0.7 (Mar 17, 2004) eth0: 21040 at 0xfffffc8602231000, 00:00:f8:22:00:ee, IRQ 29 udev: renamed network interface eth0 to eth1 I never saw any helpful error message about it. The card works fine, but it's a little bit annoying because udev thinks i have two different interfaces and I have to handle with eth0 and eth1... And I'm still trying to understand when and why it will start with a different mac address, but I don't understand the rules. Reproducible: Sometimes
alpha ~ # lspci -vv 00:06.0 Ethernet controller: Digital Equipment Corporation DECchip 21040 [Tulip] (rev 24) Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr+ Stepping- SERR+ FastB2B- DisINTx- Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 32 Interrupt: pin A routed to IRQ 29 Region 0: I/O ports at 9400 [size=128] Region 1: Memory at 02231000 (32-bit, non-prefetchable) [size=128] Kernel driver in use: de2104x Kernel modules: de2104x
Can you figure out which (of the two?) is the proper MAC address for that card?
The AlphaBIOS prints out the second address 00:00:f8:22:00:ee. It's too bad, the address is not written on the board or any sticker. To clarify wether the box has no hardware issue I did so many resets until the AlphaBIOS and linux values differ. And yes I saw it twice that AlphaBIOS shows the 00:00... value and linux got the wrong 00:f8... during the same boot process (AlphaBIOS->MILO->Linux). Finally, I would say 20% of my card initialisations have been wrong today. Nevertheless the BIOS prints always the same correct value.
As for the udev problem, you can get rid of that (persistent net devices) by removing /etc/udev/rules.d/75-persistent-net-generator.rules To have portage remove that file every time you update udev, put this in /etc/make.conf: INSTALL_MASK="/etc/udev/rules.d/75-persistent-net-generator.rules" As for the byte shifting, that sounds like wonky hardware or maybe a corner case bug in the kernel. Have you tried different kernels? Which kernel version do you currently use.
The problem appeared with a new installation, my kernel version was gentoo-sources-2.6.25-r6. But I just tried two different kernels from kernel.org (2.6.22, 2.6.27) and this strange mac shifting is always observable. Am I the only one with such a problem? I didn't found similar reports yet. I don't think it's a hardware bug. I think something is simply just unitialised.
Created attachment 168056 [details, diff] Bugfix It seems the DEC 21040 hardware is a little bit to slow for an immediate access. This patch introduces a small pause and that solves my problem. Signed-off-by: Martin Langer <martin-langer@gmx.de>
Good news: Linus applied the patch. It looks like this fix will come with kernel releases >= 2.6.28-rc1. http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=bc0da3fcec1cec11dc451b8fcb9c9ad7e4ca6e12
