Created attachment 282129 [details]
tarball of 'lspci -vvv' and 'dmesg' outputs

I have an ASRock 970A-G/3.1 motherboard, which, with current Linux kernels, occasionally "finds" an extra PCI device on the initial scan. I wouldn't mind, but it finds it early in the piece, and that changes the PCI allocation of my Ethernet board from 02:06.0 to 03:06.0, and, with systemd, Linux comes up with no network connection. A reboot fixes it, mostly.

This has been in evidence for a few months now, since I replaced the motherboard last November (old one was a different brand). I'm not sure whether it's a regression or not; I don't recall it happening until some time in January, but it may have been doing it before then. I will try to get an earlier kernel (~November) installed and see if that helps.

Problem currently always occurs on startup from cold. Restart doesn't fix it; it needs to be powered off and on again, and then it's usually ok. The box dual-boots with Windows, but I rarely run it on Windows these days.

I can't seem to find any information on what the intermittent port is. lspci labels it as

00:09.0 PCI bridge: Advanced Micro Devices, Inc. [AMD/ATI] RD890/RD9x0/RX980 PCI to PCI bridge (PCI Express GPP Port 4) (prog-if 00 [Normal decode])

(whatever that is). I don't think I have anything connected to it.

I'm attaching a tarball of 'lspci -vvv' and 'dmesg' outputs for both bad (device exists) and good (device not in evidence).Let me know if you need anything else.

Thanks,

 .....Ron

-- 
Ron Murray <rjmx@rjmx.net>
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