So
@Stork I went ahead and made the move from 10.12.6 to 10.13.4 this evening. The installation seemed to go smoothly; used the USB to boot up and made it through the upgrade (multiple reboots; assume converted to APFS). After the upgrade process completed, I booted again to the USB since it had the updated Clover and it threw up a bit more verbose message prior to showing Clover (obviously having to do with APFS):
So then the boot volume didn't appear until I moved over to the next page of images that Clover detected:
Now when I boot this, each time I get the black Apple logo loading screen, within 1 second the system reboots.
I determined that that was due to having the old M.2 drivers still in place. I deleted the two *hack* drivers from s/l/e and then found that I was still getting a problem as noted here from my verbose boot output:
I thought I'd mv the IONVMeFamily kext from s/l/e as well to see what would happen, but no luck. I then proceeded to clear the cache via another macOS installation drive:
sudo rm -r /Volumes/m2_drive/System/Library/Caches/com.apple.kext.caches
sudo touch /Volumes/m2_drive/System/Library/Extensions
sudo kextcache -update-volume /Volumes/m2_drive/
After this Unfortunately I just get a super fast panic that I'm not able to entirely catch via slo-mo on my phone. It appears to be still related to com.apple.iokit.IONVMeFamily:
Could it be due to using a Samsung 951 M.2 that was discussed in your earlier build instead of one that's perhaps not supported by macOS 10.13 out of the box? Any other thoughts?
@RehabMan perhaps you have some additional insights?
UPDATE: So I installed it fresh to an old drive I had laying around and it recognizes the M.2 just fine there, perhaps it's just the upgrade from 10.12.6 to 10.13.4 that's not working... Just glad that it recognizes my M.2 fine. Still hunting solutions since I really need to perform an upgrade vs a fresh install as I don't have the space or the time to push things around and restore apps right now. Any ideas would be much appreciated.
UPDATE 2: I seem to have perhaps solved the issue, at least in part. With the fresh new install of macOS 10.13.4, I gutted the /s/l/e and /l/e folders on the non-working upgraded macOS install reported above. I then copied (`rsync -av`) the working 10.13.4 /s/l/e and /l/e over to the non-working and refreshed the kext cache. On reboot the M.2 installation began booting properly. I then pushed over the new EFI files into the old EFI folder.
One thing I have noticed is that Clover is taking an enormous amount of time initially to scan it seems and then it again takes a long time to load and save even changes to boot options like adding "-v" to an instance to boot.
So aside from getting the slow Clover boot, everything seems to work now. Just leaving this documentation here for future reference or in case it may help someone else in some way down the road.