High CPU sys and a lot of kernel error logs

Installing and Using OpenWrt
1

I'm finding a lot of these errors on the logs:

Sat May  4 00:30:50 2024 kern.err kernel: [206837.094461] buffer_info[next_to_clean]
Sat May  4 00:30:50 2024 kern.err kernel: [206837.094461]   time_stamp           <101348390>
Sat May  4 00:30:50 2024 kern.err kernel: [206837.094461]   next_to_watch        <0000000088fba909>
Sat May  4 00:30:50 2024 kern.err kernel: [206837.094461]   jiffies              <1013b2688>
Sat May  4 00:30:50 2024 kern.err kernel: [206837.094461]   desc.status          <0>
Sat May  4 00:30:52 2024 kern.err kernel: [206839.094542] igc 0000:02:00.0 eth1: Detected Tx Unit Hang
Sat May  4 00:30:52 2024 kern.err kernel: [206839.094542]   Tx Queue             <3>
Sat May  4 00:30:52 2024 kern.err kernel: [206839.094542]   TDH                  <df>
Sat May  4 00:30:52 2024 kern.err kernel: [206839.094542]   TDT                  <df>
Sat May  4 00:30:52 2024 kern.err kernel: [206839.094542]   next_to_use          <df>
Sat May  4 00:30:52 2024 kern.err kernel: [206839.094542]   next_to_clean        <df>

I see higher than normal CPU sys utilization also. Does anybody know what is this?

2

Either very bad cable, very agressive flow control/pause frame, or wildly buggy driver.
Do:
ethtool -A eth1 tx off rx off autoneg on
ethtool -r eth1

Then examine ethtool -s eth1 for overhelming crc errors
If any replace cable.

Next ethtool eth1 and try to manually force to negotiate only single negotiated speed.

3

I'll try this as soon as I see the error again. Thank you!