Intel I350 regression 5.10 -> 5.14 ("The NVM Checksum Is Not Valid") [8086:1521]

Dear all, 

I hope this is the right place to ask, if not please advise me where to go.

I have a new Dell machine with both an Intel on-board ethernet controller 
([8086:15f9]) and an additional 2-port extension card ([8086:1521]). 

The second adaptor, a "DeLock PCIe 2xGBit", worked fine as far as I could 
see with Linux 5.10.59, but fails to initialize with Linux 5.14.9.

dilfridge ~ # lspci -nn
[...]
01:00.0 Ethernet controller [0200]: Intel Corporation I350 Gigabit Network Connection [8086:1521] (rev ff)
01:00.1 Ethernet controller [0200]: Intel Corporation I350 Gigabit Network Connection [8086:1521] (rev ff)
[...]

dilfridge ~ # dmesg|grep igb
[    2.069286] igb: Intel(R) Gigabit Ethernet Network Driver
[    2.069288] igb: Copyright (c) 2007-2014 Intel Corporation.
[    2.069305] igb 0000:01:00.0: can't change power state from D3cold to D0 (config space inaccessible)
[    2.069624] igb 0000:01:00.0 0000:01:00.0 (uninitialized): PCIe link lost
[    2.386659] igb 0000:01:00.0: PHY reset is blocked due to SOL/IDER session.
[    4.115500] igb 0000:01:00.0: The NVM Checksum Is Not Valid
[    4.133807] igb: probe of 0000:01:00.0 failed with error -5
[    4.133820] igb 0000:01:00.1: can't change power state from D3cold to D0 (config space inaccessible)
[    4.134072] igb 0000:01:00.1 0000:01:00.1 (uninitialized): PCIe link lost
[    4.451602] igb 0000:01:00.1: PHY reset is blocked due to SOL/IDER session.
[    6.180123] igb 0000:01:00.1: The NVM Checksum Is Not Valid
[    6.188631] igb: probe of 0000:01:00.1 failed with error -5

Any advice on how to proceed? Willing to test patches and provide additional debug info.

Thanks,
Andreas

-- 
PD Dr. Andreas K. Huettel
Institute for Experimental and Applied Physics
University of Regensburg
93040 Regensburg
Germany

tel. +49 151 241 67748 (mobile)
tel. +49 941 943 1618 (office)
e-mail andreas.huettel@ur.de
http://www.akhuettel.de/
http://www.physik.uni-r.de/forschung/huettel/