Yes, it would be very nice if Ubuntu applied these simple patches, but they don’t care. They knew this problem would eventually occur on LTS kernels with Ubuntu 22.04 and said as much, but as long as 390 works with with the original 22.04 kernel (5.15.x), they think that is good enough. I just wish they had made that decision before they started patching 390 for earlier LTS kernels (5.19, 6.2). Talk about inconsistency…
I signed-up for this forum just to thank you for this post. I installed your PPA and patched 390 driver, and for the first time in months my Ubuntu 22.04 is working without having to go back to the old kernel on boot.