I just did this install a couple days ago and now I have the problem where when trying to boot I get the P-State Stepper Error 18 followed by a kernel panic, and it happens quite frequently, the worst was one time it took five or six retries before I finally got it to boot. It seems random, sometimes it will boot without issue but other times this annoying problem persists. I read in another thread that one possible solution is to install the NullCPUPowerManagement.kext shown above. I'm a little confused, though - utsi says it goes in /EFI/CLOVER/kexts/10.11/NullCPUPowerManagement.kext but I don't see an EFI directory off the root directory, just one called EFI-Backups. So do you install it by directly copying it somewhere, or do you use a program like KextBeast or what? If I am supposed to use KextBeast then do I need to tell it to put it in a particular directory (/Library/Extensions or
/System/Library/Extensions)? I only ask because in the other post it said that NullCPUPowerManagement.kext should be installed to to /Library/Extensions, which is not the location utsi suggests.
Also, what impact does using NullCPUPowerManagement.kext have on the system - is this okay as a long term fix or does it take away from the system performance in any way? I want to make sure that there's no way that installing it could make my system totally unbootable, or reduce the CPU performance or anything. I really don't know how that kext operates so that's why I'm asking. Also, how difficult is it to uninstall a .kext if it does cause a problem?
Thank you! So just to be clear, if I obtain and run the EFI Mounter v3 program, I can use that mount the EFI and then copy NullCPUPowerManagement.kext to /EFI/CLOVER/kexts/10.11/NullCPUPowerManagement.kext on the system drive, and since all it controls is power management it should not degrade the operation of my system. And if for some reason I want to remove it, it's simply a matter of mounting the EFI again and deleting the NullCPUPowerManagement.kext file. And there is almost no chance that it could make my system unbootable.
If any of what I have stated above is wrong, I'd very much appreciate clarification before I go and do it!
Yes, that's the correct procedure. Deleting the kext will revert the change, that's right. But I can't guarantee that your system won't become unbootable, you never know with these builds You could always boot from a USB stick.
If all fails I have found that instead of too much troubleshooting it's usually faster to go through the install process from scratch. And if you do, try putting the NullCPUPowerManagement kext on your install USB before you start.