Comment 9 for bug 1847892

Okay - the 18.04.3 release I tested in September, which was fine, has 5.0.0-23.

-29 is broken, as mentioned above. That's a pretty narrow window to work with.
I'd prefer it if someone from Canonical took it from here.
(Heck, there are probably few enough commits to that driver in that timeframe that I could find the bad one more easily just by browsing the source than getting that machine to build it).

Since it's the HWE stack that's broken, I could still install 18.04 from the image I have and switch back to the original Bionic kernel series, though it's anybody's guess if the same regression was merged into 4.15 again as well.
Having to do a fresh install sucks pretty hard, but I'd at least be able to pin the last unbroken kernel, whereas on 19.10 there aren't any working ones in the repos at all (AFAIK) so I'm basically screwed until a fix makes its way through the system or I brute-force an older one onto it. I'm still trying to decide if I really want to go down that road or not.

I found https://people.canonical.com/~kernel/info/kernel-version-map.html , but it's basically useless. All the 4.15 kernels from the working -32 through the 7 months of buggy ones and out the other side to -55 when it was fixed are all just "4.15.18 mainline".
Maybe I'm missing something here, but without the tree that you guys are *actually building from* I don't see how me bisecting mainline is going to achieve anything. If that page is accurate it has nothing to do with mainline at all and the bug only exists in the Ubuntu tree in the first place, neh?