Can you reproduce the issue with recent kernel from unstable or buster-backports?
Tried with linux-image-5.10.0-0.bpo.7-amd64 (5.10.40-1~bpo10+1 amd64) from buster-backports. Same issue - kernel panic with bonded interfaces. Current workaround for me is to run without bonding. Cheers, spi
