After a while of heavy load I have seen the BPI R4 ethernet stop working. The network can no longer send, and after a few seconds network watchdog messages show up:

2024-11-24T05:03:30.377477-05:00 nostromo kernel: [22865.993414] mtk_soc_eth 15100000.ethernet en-lan0: NETDEV WATCHDOG: CPU: 0: transmit queue 1 timed out 5710 ms
2024-11-24T05:03:30.377532-05:00 nostromo kernel: [22866.003459] mtk_soc_eth 15100000.ethernet en-lan0: transmit timed out
2024-11-24T05:03:30.377543-05:00 nostromo kernel: [22866.009909] mtk_soc_eth 15100000.ethernet eth0: NETDEV WATCHDOG: CPU: 0: transmit queue 3 timed out 5690 ms

Happens on two different boards, so not an issue with a specific board.

This happened very rarely with the BPI provided 6.1 kernel (every few weeks), but significantly more often with the 6.11 (almost every time when a a backup runs and uploads larger amounts of data over a long period of time.But it also happened on a slower internet connection, so can't be a pure throughput issue.

I'll try to check if the network card is still receiving traffic, or if both send and received are done.