Hello Jim, I am not involved in packaging, but came to this report by chance.
The attached file contains all the changes you devs have made in the kernel configs from 5.10.28 (-6 package) to 5.10.38/.40 (-7 package). It was made with meld. ~10 kernel parameters have changed and led to this mess, so I assume it would be trivial for you to find the faulty one.
These parameters are not all that changed - there are around 1400 patches added upstream to the kernel between v5.10.28 and v5.10.38. https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/log/?h=v5.10.38 Kind regards, Bernhard