I've upgraded from Sierra to High Sierra last week. Sierra setup was perfectly fine (I'm starting to think I should have kept it !)
Now the bad part (high sierra) - when the computer is awaken after a sleep, randomly (let say 1 out of 3 time)
it goes to bios POST, clover then the multilingual error message "You need to restart your computer."
- t420s with bios mod (including whitelist + vbios)
- clover lastest (4212) from github https://github.com/tluck/Lenovo-T420-Clover
- hibernate was set 0 - it didn't changed during upgrade
$ pmset -g | grep hibernatemode
The only difference which shouldn't matter : clover config.plist mod & kext related to wifi/bt broadcom ; it was fine w/ sierra.
bdmesg output, after bad wake up:
0:796 0:005 - : 'Macintosh HD'
0:801 0:005 AddLoaderEntry for Volume Name=Macintosh HD
0:802 0:001 Check if volume Is Hibernated:
0:802 0:000 Check sleep image 'by signature':
0:805 0:002 read prefs \Library\Preferences\com.apple.PowerManagement.plist status=Success
0:805 0:000 using default sleep image name = \private\var\vm\sleepimage
0:808 0:002 sleepimage not found -> Not Found
0:808 0:000 hibernated: no - sign
it search for sleepimage, which isn't there (okay as it's configured to not creating one)
Oct 3 09:19:00 xs-MacBook-Pro com.apple.xpc.launchd (com.apple.quicklook): Endpoint has been activated through legacy launch(3) APIs. Please switch to XPC or bootstrap_check_in(): com.apple.quicklook
Oct 3 19:42:16 localhost bootlog: BOOT_TIME 1507052536 0
=> no output between those time (slept & failed wake-up)