It turns out, after building 14 different commits between v5.8 and v5.9, that a three line change in drivers/pci/controller/pci-xgene.c breaks PCI on this machine. If I revert this file and build the commit that changed it, PCI works properly. No config options changed between these commits. I suppose now it's just a matter of figuring out why this change breaks it, and how it can be fixed and applied to 5.9+. On Tue, Feb 9, 2021 at 4:03 AM Valdis Klētnieks <valdis.kletnieks@vt.edu> wrote:
On Mon, 08 Feb 2021 09:00:27 -0500, Evan T Mesterhazy said:
Thanks, Greg - good suggestion regarding `git bisect`. I was able to narrow it down to a change between 5.8 and 5.9, so maybe that's the next logical thing to do. None of the config options added between those releases seemed relevant to the issue, but perhaps one of them is and I just don't realize it.
You're probably looking for a config option that was *removed* between those releases.
-- Evan Mesterhazy etm2131@columbia.edu