Random Shutdown in Big Sur (ThunderboltNHI) driver problem

• screen turns black, with backlight still on, fans start to spin, system crashes

• note: after startup, some interesting processes appear, like MRT, using al lot of CPU power for a short wile. Apple's standard procedure after something indefinite happened?

1. using a corroded power-connector (just replaced)

2. upgrade to Big Sur

3. putting in a new battery

4. using a 45W power adapter.

I just updated to Big Sur and have been following sf98723's guidance. I'm having trouble on step 5 when I attempt to mount MacOS (mine is called Macintosh HD).

Typing:

mount -uw /Volumes/Macintosh HD

Resulted in:

mount: unknown special file or file system /Volumes/Macintosh.

I saw someone added a space between '-' and 'uw' so I tried that:

mount - uw /Volumes/Macintosh HD

Resulted in:

usage: mount [-dfruvw] [-o options] [-t external_type] special mount_point
       mount [-adfruvw] [-t external_type]
       mount [-dfruvw] special | mount_point

Am I doing something wrong here?

Using Macbook Pro 15 Late 2013

I'm running into the same issue as @luke101 when I attempt to mount Macintosh HD in my 15" MBP (Late 2014). I've been unable to mount the drive to continue with the procedure.

Any guidance on how I might work around this?

I've tried all of the suggestions regarding " ", , _, and others to try to identify the name of the drive, but the issue still seems to exist because of the space between "Macintosh" & "HD".

Any help would be appreciated, and until I get this figured out my MBP is essentially a brick...that works great on Windows 10 on Bootcamp :(

Is anyone able to verify if the steps mentioned in @sf98723 post work for Macbook Pro late 2013?

So these steps used to work until the latest update. (11.6.1 (20G224))

Before this version these steps would stop the Thunderbolt from starting. But with the latest update it not working for me anymore. I am still getting the reboots.

Has anyone managed to use the steps listed to work on this version?

kextstat | grep NHI

Executing: /usr/bin/kmutil showloaded No variant specified, falling back to release    74    0 0xffffff8001a27000 0x30000    0x30000    com.apple.driver.AppleThunderboltNHI (7.2.8) 7032BF7B-7F15-3533-A27B-06F4BBFB99E0 <73 14 13 7 6 5 3 1>

Hello, did anybody figure a fix for this? My 2014 Macbook Pro sporadically restart. It does NOT do that when I have it plugged to Cinema Display. This started happening when I updated to BigSur. Thanks

I can confirm the fixes listed in this thread work for Big Sur 11.6.1 Macbook Pro Mid 2014.

Hi can someone please help im getting stuck on the last command i keep getting unknown option '--bootefi'

Hello All, I have followed the steps and able to delete AppleThunderboltNHI.kext but still I have random shut down of my macbook pro mid 2014 model. Any other NHI.kext do I need to remove? Any suggestions would really helpful.

I had been putting off updating my mid-2014 because I didn't want to go through this process again, but I updated without thinking. I now have Big Sur 11.6.5 and the steps for this no longer work because the drive can't be mounted as writeable. I've tried a myriad of things after scouring the web and haven't found anything that works. When I try to delete/rename the AppleThunderboltNHI.kext, it keeps telling me it's a read only file system. I have verified that csrutil and authenticated-root is disabled.

Any suggestions by anyone?

Big Sur 11.6.5 now working on my Macbook Pro late-2013. The procedure outlined by @sf98723 worked for my 11.1 upgrade, but not 11.6.5. Similar procedure that worked for me - https://forums.macrumors.com/threads/big-sur-and-applethunderboltnhi-kext.2267818/page-4?post=30708345#post-30708345. Key items:

		1. Look for "rebuilding" output from this command:
         bash-3.2# kmutil install -u --force --volume-root /Volumes/Mac*HD
		checking collections...
		Warning: com.apple.driver.KextExcludeList was not found!
		considering release out-of-date because of --force
		rebuilding release collections: boot, system
		rebuilding release collections:
			boot kernel collection
			system kext collection
		rebuilding local auxiliary collection
		

2. Added this step missing from original procedure:
		$ kextcache -i /

Post #64 (open core legacy patcher) from the above link may be easier, but I read it too late.

Guys I want to jump in and give a Big Thank You to the contributors of this thread.

I have a Mac Pro 2013 (trashcan) and everytime I would woud try to upgrade to anything past Catalina I would be hit with severe kernel panics and reboots. I was VERY bad. At first I thought it was caused by my Drobo External storage and its accompanying software (the software is needed to communicate with the storage via Thunderbolt) and since I needed my external storage removing it (and thus upgrading) was out of the question. When Monterey came out I thought surely Apple had taken a look at my dozens and dozens of crash report submissions and fixed the issue. Unfortunately this was not the case and my Mac was crippled by reboots and panics. I disconnected the drive and uninstalled the software and drivers and that gave me a brief reprieve but the random restarts returned shortly after.

It even did this with a freshly installed version of Monterey and so I knew I was in trouble. I was beginning to fear that a GPU problem was the ultimate root of the matter as these GPUs are said to go bad prematurely. I happened upon this thread as I searched for solutions. Since I had no issues whatsoever on Mavericks-Catalina I reasoned that it was primarily an issue with the OS even if it caused my hardware to misbehave.

I followed the steps listed above and changed the name of the offending kext and I havent had a single freeze or reboot since.

My monitor has always used thunderbolt (mini-DP to HDMI) so I know its working without issue (at least for putting out video). I will reinstall/reconnect the Drobo software and enclosure in a day or 2 after ensuring I have a stable crash free system. Hope all goes well!

Thank you again