macOS 11 Big Sur on Unsupported Macs Thread

[quaccOS]

I just wrote two scripts to automatically apply my prelinkedkernel fix to a BigSur installation:

1) "BigSur prelinkedkernel fix.command" is for those who want to use the prelinkedkernel instead of BootKernelExtensions.kc (even on Metal GPU mac it will work)

2) "BigSur prelinkedkernel fix2.command" is mainly for those who want to fix telemetry kp and legacy usb (maybe also sound and wifi) without using opencore, or for those who use USBOpenCoreAPFSloader3 (needed for non-APFS mac)

Both the script can be launched from Finder with double click (hold ctrl and open to allow unidentified developer) through a Catalina normal booting, HighSierra, Mojave (the macOS that can use APFS containers in few words), even directly from BigSur .

Fix 2 script does not work for me – could be because of bad Ethernet connection on Big Sur. I used your prelinkedkernel file to replace mine, and I can now boot without the OpenCore menu.

Still no Wi-Fi/audio/graphics etc…and there is a lot to read in this thread — but is this all related to snapshots booting?
If disabling/deleting APFS snapshots is key to this, then that's where I screwed up… Edit: I can still perform all necessary writes to system disk from BS Recovery USB anyway
All attempts to stop snapshots failed. Error 66, Error 77, Unknown/Special Filesystem

 

[TimothyR734]

Fix 2 script does not work for me – could be because of bad Ethernet connection on Big Sur. I used your prelinkedkernel file to replace mine, and I can now boot without the OpenCore menu.

Still no Wi-Fi/audio/graphics etc…and there is a lot to read in this thread — but is this all related to snapshots booting?
If disabling/deleting APFS snapshots is key to this, then that's where I screwed up… Edit: I can still perform all necessary writes to system disk from BS Recovery USB anyway
All attempts to stop snapshots failed. Error 66, Error 77, Unknown/Special Filesystem

I am in the same boat as you have to use my USBOpenCoreAPFSloader usb to boot into Big Sur and didn't make it in time before the snapshot sealed so no wifi

 

[TimothyR734]

[automerge]1593737769[/automerge]
In macOS Catalina my Big Sur Beta SSD says Update and this is how it looks in Disk utility

 

[jhowarth]

I just wrote two scripts to automatically apply my prelinkedkernel fix to a BigSur installation:

1) "BigSur prelinkedkernel fix.command" is for those who want to use the prelinkedkernel instead of BootKernelExtensions.kc (even on Metal GPU mac it will work)

2) "BigSur prelinkedkernel fix2.command" is mainly for those who want to fix telemetry kp and legacy usb (maybe also sound and wifi) without using opencore, or for those who use USBOpenCoreAPFSloader3 (needed for non-APFS mac)

Both the script can be launched from Finder with double click (hold ctrl and open to allow unidentified developer) through a Catalina normal booting, HighSierra, Mojave (the macOS that can use APFS containers in few words), even directly from BigSur .

I am seeing some really baffling behavior on a MacPro 3,1 using the commands listed in "BigSur prelinkedkernel fix2.command" to install a copy of the prelinkedkernel manually downloaded from...

https://raw.githubusercontent.com/jacklukem/BigSurfixes/master/patched%20prelinkedkernel%20beta1/prelinkedkernel.zip

and unzipped before installation. When following those steps from Catalina on a copy of Big Sur installed on a usb external drive, the resulting volume successfully boots but then seems unable to access the usb keyboard or mouse. So we seem to have enough legacy usb support to boot from a usb drive but not use usb input devices. Bizarre.

 

[jhowarth]

I am seeing some really baffling behavior on a MacPro 3,1 using the commands listed in "BigSur prelinkedkernel fix2.command" to install a copy of the prelinkedkernel manually downloaded from...

https://raw.githubusercontent.com/jacklukem/BigSurfixes/master/patched%20prelinkedkernel%20beta1/prelinkedkernel.zip

and unzipped before installation. When following those steps from Catalina on a copy of Big Sur installed on a usb external drive, the resulting volume successfully boots but then seems unable to access the usb keyboard or mouse. So we seem to have enough legacy usb support to boot from a usb drive but not use usb input devices. Bizarre.

Okay. Some progress. Using this prelinkedkernel provides usable usb input devices.

jacklukem/BigSurfixes

Big Sur fixes for unsupported Mac. Contribute to jacklukem/BigSurfixes development by creating an account on GitHub.

github.com

However, it still lacks wifi and sound support on a MacPro 3,1.

 

[vinaypundith]

Can someone summarize what's been done so far, as far as what is having to be done to get different features working? Among the 55 pages of this thread, I cannot find what the proper way to install Big Sur in the first place is. Some people have used OpenCore to spoof to a supported machine, some have used CatalinaOTASwufix to upgrade from Catalina, and yet some others seem to have made a bootable installer that works. What is the best way to do it, at this stage?

 

[TimothyR734]

Michael Tsai - Blog - Big Sur’s Hidden Containers Folder

mjtsai.com

 

[jhowarth]

Can someone summarize what's been done so far, as far as what is having to be done to get different features working? Among the 55 pages of this thread, I cannot find what the proper way to install Big Sur in the first place is. Some people have used OpenCore to spoof to a supported machine, some have used CatalinaOTASwufix to upgrade from Catalina, and yet some others seem to have made a bootable installer that works. What is the best way to do it, at this stage?

From what I have been able to puzzle out tonight, it looks like anything that you can place in /Library/Extensions, without a pre-existing copy being present in /System/Library/Extensions, can produce a usable prelinkedkernel using the Kext-Droplet application. Replacing pre-existing kernel extensions in /System/Library/Extensions seems to still be an unresolved issue.

I have confirmed that the Catalina Patcher copies of LegacyUSBInjector.kext, LegacyUSBVideoSupport.kext and even AppleIntelPIIXATA.kext can be installed with Kext-Droplet. However, I have had no luck booting into the recovery partition under Big Sur in order to disable authenticated-root to allow mounting a snapshot for replacing AppleHDA.kext and IO80211Family.kext in /System/Library/Extensions.

I tried the workaround suggested of copying Big Sur's csrutil so that it can be run under Catalina's recovery partition. However that failed as the Big Sur copy of csrutil seems to want to be run under Big Sur's rather than Catalina's recovery partition.

 

[Alex-Microsmeta]

View attachment 930151 View attachment 930152
[automerge]1593737769[/automerge]
In macOS Catalina my Big Sur Beta SSD says Update and this is how it looks in Disk utility

@jackluke ...Me too. Exact issues. I'm trying to make a clone of working BS but Catalina seems unable (disk not compatible with this volume) and BS recovery has failed the first trial. Also I cannot restore the BS container image.dmg correctly created because it is not and APFS image

 

[jackluke]

@jackluke ...Me too. Exact issues. I'm trying to make a clone of working BS but Catalina seems unable (disk not compatible with this volume) and BS recovery has failed the first trial. Also I cannot restore the BS container image.dmg correctly created because it is not and APFS image

If the BigSur System volume (and its APFS container) is sealed (as many install on this thread), then you can use only the USB BigSur Installer DiskUtility (or Time Machine) to restore the backup.

 

[Alex-Microsmeta]

I just wrote two scripts to automatically apply my prelinkedkernel fix to a BigSur installation:

1) "BigSur prelinkedkernel fix.command" is for those who want to use the prelinkedkernel instead of BootKernelExtensions.kc (even on Metal GPU mac it will work)

2) "BigSur prelinkedkernel fix2.command" is mainly for those who want to fix telemetry kp and legacy usb (maybe also sound and wifi) without using opencore, or for those who use USBOpenCoreAPFSloader3 (needed for non-APFS mac)

Both the script can be launched from Finder with double click (hold ctrl and open to allow unidentified developer) through a Catalina normal booting, HighSierra, Mojave (the macOS that can use APFS containers in few words), even directly from BigSur .

Hi,
Big Sur loads fine now, but only loading from OpenCoreAPFSloader3
Works only with Apple bluetooth keyboard and mouse. We need a way to clone the working installation. Catalina doent's see BigSur Volume, and mount a volumes called "Update" and "BigSur - Data" . Disk Utility crashes (closes) after launch due to the Big Sur Container. I have try to clone it with BS recovery. it start, but then return an error. Wifi is still unavailable after patching. I have also tried to fix wifi with the new kext copied in /Extensions/ from BS Recovery, without errors but unsuccesfully (image attached)

I am seeing some really baffling behavior on a MacPro 3,1 using the commands listed in "BigSur prelinkedkernel fix2.command" to install a copy of the prelinkedkernel manually downloaded from...

https://raw.githubusercontent.com/jacklukem/BigSurfixes/master/patched%20prelinkedkernel%20beta1/prelinkedkernel.zip

and unzipped before installation. When following those steps from Catalina on a copy of Big Sur installed on a usb external drive, the resulting volume successfully boots but then seems unable to access the usb keyboard or mouse. So we seem to have enough legacy usb support to boot from a usb drive but not use usb input devices. Bizarre.

 

[jackluke]

From what I have been able to puzzle out tonight, it looks like anything that you can place in /Library/Extensions, without a pre-existing copy being present in /System/Library/Extensions, can produce a usable prelinkedkernel using the Kext-Droplet application. Replacing pre-existing kernel extensions in /System/Library/Extensions seems to still be an unresolved issue.

I have confirmed that the Catalina Patcher copies of LegacyUSBInjector.kext, LegacyUSBVideoSupport.kext and even AppleIntelPIIXATA.kext can be installed with Kext-Droplet. However, I have had no luck booting into the recovery partition under Big Sur in order to disable authenticated-root to allow mounting a snapshot for replacing AppleHDA.kext and IO80211Family.kext in /System/Library/Extensions.

I tried the workaround suggested of copying Big Sur's csrutil so that it can be run under Catalina's recovery partition. However that failed as the Big Sur copy of csrutil seems to want to be run under Big Sur's rather than Catalina's recovery partition.

Some machines might try different prelinkedkernel, I uploaded some but other requires USBOpenCoreAPFSloader3 or to boot with CMD+S .

About Wifi if your Catalina mac uses AirPortBrcmNIC driver, then in my prelinkedkernel I embedded the IO80211Family.kext patched, so the stock BigSur Wifi I guess won't work in this case, for sound try some external USB or bluetooth speaker, for internal audio card MacPro requires a different AppleHDA.kext rather than the HighSierra one.

I doubt that third party system kext will work when installed in this BigSur path /Library/Extensions/

When you use my prelinkedkernel fix, to rebuild a kernel cache you should use this instead of kmutil:
kextcache -i / ; kcditto

For now from a non-APFS or legacy usb Mac you can't use an USB BigSur Installer or BigSur Recovery, but I am trying to make a patched one for BootKernelExtensions.kc and BaseSystem.dmg .

Without BigSur Recovery, to use "csrutil authenticated-root disable" you can use the ASentientBot patched boot.efi :
https://forums.macrumors.com/thread...unsupported-macs-thread.2242172/post-28604525

You should replace it here: /Volumes/Preboot/UUID-Preboot/System/Library/CoreServices/

dosdude1 advised to replace also in this path BigSurSystem : /usr/standalone/i386/
[automerge]1593767141[/automerge]

Hi,
Big Sur loads fine now, but only loading from OpenCoreAPFSloader3
Works only with Apple bluetooth keyboard and mouse. We need a way to clone the working installation. Catalina doent's see BigSur Volume, and mount a volumes called "Update" and "BigSur - Data" . Disk Utility crashes (closes) after launch due to the Big Sur Container. I have try to clone it with BS recovery. it start, but then return an error. Wifi is still unavailable after patching. I have also tried to fix wifi with the new kext copied in /Extensions/ from BS Recovery, without errors but unsuccesfully (image attached)

When you applied the prelinkedkernel fix, from BigSur normal booting you should use kextcache -i / ; kcditto rather than "kmutil" that is only for BootKernelExtensions.kc .

 

[jackluke]

Fix 2 script does not work for me – could be because of bad Ethernet connection on Big Sur. I used your prelinkedkernel file to replace mine, and I can now boot without the OpenCore menu.

Still no Wi-Fi/audio/graphics etc…and there is a lot to read in this thread — but is this all related to snapshots booting?
If disabling/deleting APFS snapshots is key to this, then that's where I screwed up… Edit: I can still perform all necessary writes to system disk from BS Recovery USB anyway
All attempts to stop snapshots failed. Error 66, Error 77, Unknown/Special Filesystem

Try this from BigSur normal booting, open terminal:

mount

use "mount" detect the root mount point of your BigSur System (snapshot) example a generic "diskXsYsZ"
"sZ" is a "locked snapshot" (from where you are booting) so you don't write it in next command

sudo mount -o nobrowse -t apfs /dev/diskXsY /Volumes/AnyDiskLabel/AnyEmptyFolder/

AnyDiskLabel is an already mounted disk on your Mac
AnyEmptyFolder is an empty folder that you make on that disk

your non-snapshot System mounted diskXsY should have this mount point:

/Volumes/AnyDiskLabel/BigSurLabel/

(AnyEmptyFolder is your BigSurLabel after used as mount point)

then replace your kext here:

/Volumes/AnyDiskLabel/BigSurLabel/System/Library/Extensions/

(chown and chmod the kext before replace)

after you replaced, if you used the prelinkedkernel method you should use this:

kextcache -i / ; kcditto

then make a new bootable snapshot with embedded patched kext:

bless --folder /Volumes/AnyDiskLabel/BigSurLabel/System/Library/CoreServices --bootefi --create-snapshot

 

[brandonsierra]

Hey Guys, How ya all doing here?

 

[Alex-Microsmeta]

I just wrote two scripts to automatically apply my prelinkedkernel fix to a BigSur installation:

1) "BigSur prelinkedkernel fix.command" is for those who want to use the prelinkedkernel instead of BootKernelExtensions.kc (even on Metal GPU mac it will work)

2) "BigSur prelinkedkernel fix2.command" is mainly for those who want to fix telemetry kp and legacy usb (maybe also sound and wifi) without using opencore, or for those who use USBOpenCoreAPFSloader3 (needed for non-APFS mac)

Both the script can be launched from Finder with double click (hold ctrl and open to allow unidentified developer) through a Catalina normal booting, HighSierra, Mojave (the macOS that can use APFS containers in few words), even directly from BigSur .

edit:

added "BigSur prelinkedkernel fix3.command" for any non-APFS and legacy USB Mac (works also without opencore)

@jackluke @TimothyR734 FIX 3 is PERFECT! @dosdude1 @ASentientBot @parrotgeek1

-Fixed USB keyboard and USB wired mouse (that works better than Magic Mouse (no right mouse functions)
-Fixed Wifi!!!!! I'm writing from Big Sur Safari that is quite fast also without Graphic Acceleration.

@jackluke I have tried to clone Big Sur APFS container to a BS BKP APFS container using BS recovery. It starts, but if fails at the end.

 

[jhowarth]

Try this from BigSur normal booting, open terminal:

mount

use "mount" detect the root mount point of your BigSur System (snapshot) example a generic "diskXsYsZ"
"sZ" is a "locked snapshot" (from where you are booting) so you don't write it in next command

sudo mount -o nobrowse -t apfs /dev/diskXsY /Volumes/AnyDiskLabel/AnyEmptyFolder/

AnyDiskLabel is an already mounted disk on your Mac
AnyEmptyFolder is an empty folder that you make on that disk

your non-snapshot System mounted diskXsY should have this mount point:

/Volumes/AnyDiskLabel/BigSurLabel/

(AnyEmptyFolder is your BigSurLabel after used as mount point)

then replace your kext here:

/Volumes/AnyDiskLabel/BigSurLabel/System/Library/Extensions/

(chown and chmod the kext before replace)

after you replaced, if you used the prelinkedkernel method you should use this:

kextcache -i / ; kcditto

then make a new bootable snapshot with embedded patched kext:

bless --folder /Volumes/AnyDiskLabel/BigSurLabel/System/Library/CoreServices --bootefi --create-snapshot

The snapshot method instructions above work when booted from the legacy usb prelinked kernel except for the very last step. While the command...

kextcache -i / ; kcditto

shows no errors, when I execute...

bless --folder /Volumes/AnyDiskLabel/BigSurLabel/System/Library/CoreServices --bootefi --create-snapshot

or

bless --folder /System/Library/CoreServices --bootefi --create-snapshot

I get an error...

"Couldn't create /Volumes/AnyDiskLabel/BigSurLabel/System/Library/CoreServices: operation not permitted'

or

"Couldn't create /System/Library/CoreServices: operation not permitted'

FYI, using /Volumes/AnyDiskLabel/BigSurLabel/System/Library/CoreServices doesn't seem right since the snapshot is already mounted in /, right? Also, the above bless command fails when executed using 'sudo' or executed under a shell running through sudo.

The bless command seems to require cryptographic verification being turned off.

 

[jackluke]

The snapshot method instructions above work when booted from the legacy usb prelinked kernel except for the very last step. While the command...

kextcache -i / ; kcditto

shows no errors, when I execute...

bless --folder /Volumes/AnyDiskLabel/BigSurLabel/System/Library/CoreServices --bootefi --create-snapshot

or

bless --folder /System/Library/CoreServices --bootefi --create-snapshot

I get an error...

"Couldn't create /Volumes/AnyDiskLabel/BigSurLabel/System/Library/CoreServices: operation not permitted'

or

"Couldn't create /System/Library/CoreServices: operation not permitted'

FYI, using /Volumes/AnyDiskLabel/BigSurLabel/System/Library/CoreServices doesn't seem right since the snapshot is already mounted in /, right? Also, the above bless command fails when executed using 'sudo' or executed under a shell running through sudo.

The bless command seems to require cryptographic verification being turned off.

Since currently the legacy USB Mac can't boot a BigSur Recovery, I guess you need this:
https://forums.macrumors.com/thread...unsupported-macs-thread.2242172/post-28604525

that is ASentientBot "BigSur patched boot.efi" to disable authenticated-root, I guess it is suffice to replace it here:

/Volumes/Preboot/UUID-BigSur/System/Library/CoreServices/

About Wifi which AirPortBrcm driver do you use on Catalina ?

 

[siciov]

Finally i install Big Sur on MacBook 6,1 via guide https://github.com/jacklukem/BigSurfixes

 

[jhowarth]

Since currently the legacy USB Mac can't boot a BigSur Recovery, I guess you need this:
https://forums.macrumors.com/thread...unsupported-macs-thread.2242172/post-28604525

that is ASentientBot "BigSur patched boot.efi" to disable authenticated-root, I guess it is suffice to replace it here:

/Volumes/Preboot/UUID-BigSur/System/Library/CoreServices/

About Wifi which AirPortBrcm driver do you use on Catalina ?

My IO80211Family.kext under Catalina is 1200.12.2 so it appears that Catalina Patcher is leaving the Catalina version present for the installed BCM94360CD wifi card.

I suspect I will need to completely start over again since the unblessed snapshot is now fouling the boot of Big Sur now.

 

[jackluke]

My IO80211Family.kext under Catalina is 1200.12.2 so it appears that Catalina Patcher is leaving the Catalina version present for the installed BCM94360CD wifi card.

I suspect I will need to completely start over again since the unblessed snapshot is now fouling the boot of Big Sur now.

Without a BigSur Recovery (or USB BigSur Installer with responsive usb devices), isn't easy to manage its locked snapshots, anyway this time use the ASentientBot Hax3.dylib to re-install: https://forums.macrumors.com/thread...unsupported-macs-thread.2242172/post-28619108

this should disable also the BigSur sealed volume (so you can use "sudo mount -uw /").

For that Wifi card you can use the stock BigSur IO80211Family.kext , don't need to replace it, I provided also in some post a prelinkedkernel with stock BigSur Wifi kext .

 

[jhowarth]

Without a BigSur Recovery (or USB BigSur Installer with responsive usb devices), isn't easy to manage its locked snapshots, anyway this time use the ASentientBot Hax3.dylib to re-install: https://forums.macrumors.com/thread...unsupported-macs-thread.2242172/post-28619108

this should disable also the BigSur sealed volume (so you can use "sudo mount -uw /").

For that Wifi card you can use the stock BigSur IO80211Family.kext , don't need to replace it, I provided also in some post a prelinkedkernel with stock BigSur Wifi kext .

Is that prelinkedkernel posted on https://github.com/jacklukem/BigSurfixes? I tried the one at...

jacklukem/BigSurfixes

Big Sur fixes for unsupported Mac. Contribute to jacklukem/BigSurfixes development by creating an account on GitHub.

github.com

but that didn't produce a wifi device.

One other question about snapshots. Where do they 'live' once you have blessed them and rebooted? Do you they always appear to reside at the original mount point of /Volumes/AnyDiskLabel/BigSurLabel? I ask because if you created the mount point in a user directory that would appear to prevent that user account from ever being deleted in the future, no?

 

[jackluke]

Is that prelinkedkernel posted on https://github.com/jacklukem/BigSurfixes? I tried the one at...

but that didn't produce a wifi device.

Probably I've updated and changed the previous file, I should make a new prelinkedkernel with stock IO80211Family.kext, meanwhile try this from a BigSur terminal:
open /System/Library/PreferencePanes/Network.prefPane

and select manually from there the Wifi network, it could work.

From your Catalina what's the output: kextstat | grep AirPort

 

[jhowarth]

Probably I've updated and changed the previous file, I should make a new prelinkedkernel with stock IO80211Family.kext, meanwhile try this from a BigSur terminal:
open /System/Library/PreferencePanes/Network.prefPane

and select manually from there the Wifi network, it could work.

From your Catalina what's the output: kextstat | grep AirPort

% kextstat | grep AirPort


70 0 0xffffff7f822ec000 0x7bc000 0x7bc000 com.apple.driver.AirPort.BrcmNIC (1400.1.1) 0F1637EA-51B0-3A81-9433-956A19427984 <69 68 67 19 13 8 7 6 5 3 1>

Currently reinstalling from scratch on a supported machine and will disable authenticated-root in csrutil under the recovery partition there. Since I am so close to rebuilding prelinked kernels here, I want to give that another go.

Back to the snapshot question, am I correct to assume that after the snapshot is blessed and rebooted that it becomes the operational mount point and loses its dependency on the original /Volumes/AnyDiskLabel/BigSurLabel mount point? That is, it replaces the original / mount point and assumes that path in /volumes?

 

[Flacko]

Probably I've updated and changed the previous file, I should make a new prelinkedkernel with stock IO80211Family.kext, meanwhile try this from a BigSur terminal:
open /System/Library/PreferencePanes/Network.prefPane

and select manually from there the Wifi network, it could work.

From your Catalina what's the output: kextstat | grep AirPort

If this helps, both my cMP3.1 (using patcher) and cMP5.1 (unpatched using OC) are using com.apple.driver.AirPort.BrcmNIC (1400.1.1) for the BCM94360CD in Catalina 15.5.

 

[jackluke]

% kextstat | grep AirPort


70 0 0xffffff7f822ec000 0x7bc000 0x7bc000 com.apple.driver.AirPort.BrcmNIC (1400.1.1) 0F1637EA-51B0-3A81-9433-956A19427984 <69 68 67 19 13 8 7 6 5 3 1>

Currently reinstalling from scratch on a supported machine and will disable authenticated-root in csrutil under the recovery partition there. Since I am so close to rebuilding prelinked kernels here, I want to give that another go.

Back to the snapshot question, am I correct to assume that after the snapshot is blessed and rebooted that it becomes the operational mount point and loses its dependency on the original /Volumes/AnyDiskLabel/BigSurLabel mount point? That is, it replaces the original / mount point and assumes that path in /volumes?

If this helps, both my cMP3.1 (using patcher) and cMP5.1 (unpatched using OC) are using com.apple.driver.AirPort.BrcmNIC (1400.1.1) for the BCM94360CD in Catalina 15.5.

com.apple.driver.AirPort.BrcmNIC is a BigSur Wifi ac supported card, so it doesn't require any patched IO80211Family.kext .

Disabling csrutil authenticated-root from a supported machine won't work on an unsupported Mac because it must be disabled from the target machine since it's a new nvram csr-active-config value.
I also doubt that this can be done from a non-APFS Mac .

After BigSur Recovery csrutil authenticated-root disable, this is the "new BigSur SIP disabled" (from my current BigSur normal booting terminal) nvram csr-active-config: csr-active-config=w%08%00%00

in hex from a stock BigSur terminal conversion: 0x00000867
(in my case when using USBopencore is 0x00000877 , but the main change is the 08 )

So use the ASentientBot patched boot.efi and Hax3.dylib that disables also system volume sealing.

About snapshot I have them disabled, but I assume that loses dependency on the temporary mount point from where you make a new snapshot, so it should work even if you use an USB flash drive and then unplug it.