macOS 11 Big Sur on Unsupported Macs Thread

[jackluke]

Hi jackluke, I followed your instruction to reboot to USBOpencore and then boot to "macOS Installer" with CMD+S and I got what you see in pic 1.

Thanks.

View attachment 964148

Then since you are installing with Legacy USB Mac on external USB disk (on internal SATA disk "macOS Installer" continues with few issues), I guess for this stage2 installer you should replace the BaseSystem.dmg and BKE on that "macOS Install Data" path, but if do you have an already installed external USB BigSur, could you try to plug it to your MacBook5,1 and then use USBopencore with CMD+S and exit to check if you can boot to desktop.

 

[air.man]

Cancelled

 

[jackluke]

I haven't any other instance of BigSur installation for MB5,1. So please where I can find your original patched files?
Thanks.

From your signature you could install BigSur on external USB from other "non legacy" USB Mac then boot directly through USBopencore with CMD+S and exit on your MacBook5,1 .

Anyway to try fix the stage2 installer on Legacy USB targeting an external USB disk, I just made a script.

edit:
This attached is for this scenario:

- continue "macOS Installer" (made with BaseSystem fix) on a non-APFS Legacy USB Mac where BigSur "macOS Install Data" is created on an external USB disk, that means you are installing BigSur on an external USB SSD or HDD.

Instead if you choose to install BigSur on an internal SATA disk even with Legacy USB, this fix is not required.

@hvds already tested this behaviour, it's a limitation of LegacyUSBInjector.kext since Catalina OTA updates (and APFS Mojave too) where "macOS Installer" stage2 cannot continue properly if the "macOS Install Data" target is an external USB root, unless through USBopencore (with Catalina) and from BigSur also with a patched BaseSystem, while it can continue easier if the target is an internal SATA disk.

 

[Barry K. Nathan]

This instead should work on BigSur too but instead of kextcache it requires a kmutil snapshot kext installation and @Barry K. Nathan could test it: IntelHD3000 VRAM increase pre-patched HighSierra/Mojave/Catalina

after kext patch to verify the VRAM increase just use this app: https://apps.apple.com/br/app/opengl-extensions-viewer/id444052073?l=en&mt=12

Note the amount of VRAM listed by the app. (On this same Mac, About This Mac shows 384MB VRAM.)

I would like to remind everyone that we're talking about the Intel HD 3000, which does not support Metal and does not have acceleration under Big Sur.

I tried the 2048MB version of the patch and it actually reduced performance for me -- minimizing a Safari window takes 14 seconds without the patch and 16 seconds with the patch. (Not too surprising; the extra VRAM doesn't help because the shaders are running on the CPU not the GPU, and the CPU's performance suffers from the loss of RAM.)

 

[jackluke]

View attachment 964150
Note the amount of VRAM listed by the app. (On this same Mac, About This Mac shows 384MB VRAM.)

I would like to remind everyone that we're talking about the Intel HD 3000, which does not support Metal and does not have acceleration under Big Sur.

I tried the 2048MB version of the patch and it actually reduced performance for me -- minimizing a Safari window takes 14 seconds without the patch and 16 seconds with the patch. (Not too surprising; the extra VRAM doesn't help because the shaders are running on the CPU not the GPU, and the CPU's performance suffers from the loss of RAM.)

Right, that patch requires at least an OpenGL acceleration on IntelHD3000 that through ASentientBot non Metal patches worked on Mojave and Catalina, but not on BigSur because there is no acceleration for that GPU , anyway if OpenGL or non Metal acceleration is achieved (this is very hard) those kext should work.

@justperry could confirm that already tested a very similar method for IntelHD4000 on BigSur worked: https://forums.macrumors.com/threads/hd4000-driver-hack-for-custom-vram-size.1573528/post-28378339 and also reducing VRAM worked to have more RAM: https://forums.macrumors.com/threads/hd4000-driver-hack-for-custom-vram-size.1573528/post-28380525

 

[Alex-Microsmeta]

Right, that patch requires at least an OpenGL acceleration on IntelHD3000 that through ASentientBot non Metal patches worked on Mojave and Catalina, but not on BigSur because there is no acceleration for that GPU , anyway if OpenGL or non Metal acceleration is achieved (this is very hard) those kext should work.

@justperry could confirm that already tested a very similar method for IntelHD4000 on BigSur worked: https://forums.macrumors.com/threads/hd4000-driver-hack-for-custom-vram-size.1573528/post-28378339 and also reducing VRAM worked to have more RAM: https://forums.macrumors.com/threads/hd4000-driver-hack-for-custom-vram-size.1573528/post-28380525

Ready to test it

 

[air.man]

From your signature you could install BigSur on external USB from other "non legacy" USB Mac then boot directly through USBopencore with CMD+S and exit on your MacBook5,1 .

Anyway to try fix the stage2 installer on Legacy USB targeting an external USB disk, I just made a script.

edit:
This attached is for this scenario:

- continue "macOS Installer" (made with BaseSystem fix) on a non-APFS Legacy USB Mac where BigSur "macOS Install Data" is created on an external USB disk, that means you are installing BigSur on an external USB SSD or HDD.

Instead if you choose to install BigSur on an internal SATA disk even with Legacy USB, this fix is not required.

@hvds already tested this behaviour, it's a limitation of LegacyUSBInjector.kext since Catalina OTA updates (and APFS Mojave too) where "macOS Installer" stage2 cannot continue properly if the "macOS Install Data" target is an external USB root, unless through USBopencore (with Catalina) and from BigSur also with a patched BaseSystem, while it can continue easier if the target is an internal SATA disk.

Thank you very much for all your help. I really don't know why it doesn't work..



Yes, I have a BigSur installation running on my MBP8,2. So I tried to boot from it, but I got exactly the same behavior (forbidden sign, and same listing with CMD+S).

 

[jackluke]

Thank you very much for all your help. I really don't know why it doesn't work..

View attachment 964167

Yes, I have a BigSur installation running on my MBP8,2. So I tried to boot from it, but I got exactly the same behavior (forbidden sign, and same listing with CMD+S).

Before run the script, you need to plug the "USB Install macOS Big Sur Beta" (BaseSystem b9 legacy USB fix and fix2) because from there the patched BaseSystem is copied, it also makes a BaseSystembackup.dmg .

I wrote a condition on this new stage2 script that require also that BaseSystembackup, you can check from terminal with: ls /Volumes/*/BaseSystem/BaseSystembackup.dmg

After the patch you should notice in that "macOS Install Data" folder a new BaseSystem size 620 MB (from your picture the BaseSystem 661 MB is still the stock beta 9 incompatible with Legacy USB) and in "Locked Files" a BKE (prelinkedkernel) size of 25 MB (while the stock beta 9 one is 65 MB).

There was an issue on the script about unlock the "Locked Files", just fixed so redownload (updated also on previous post): BigSur BaseSystem stage2 installer fix.zip

 

[Alex-Microsmeta]

There was an issue on the script, just fixed so redownload (updated also on previous post): BigSur BaseSystem stage2 installer fix.zip

Before run the script, you need to plug the "USB Install macOS Big Sur Beta" (BaseSystem b9 fixed) because from there the patched BaseSystem is copied.

I wrote a condition on the script that require a backup of BaseSystem, check from terminal with: ls /Volumes/*/BaseSystem/BaseSystembackup.dmg

After the patch you should notice in that "macOS Install Data" folder a new BaseSystem size 620 MB (from your picture the BaseSystem 661 MB is still the stock beta 9 incompatible with Legacy USB) and in "Locked Files" a BKE (prelinkedkernel) size of 25 MB (while the stock beta 9 one is 65 MB).

This fix could be useful also for me to fix usb and mouse on Mac mini 2010? USB mic & webcam, internal audio and wifi already work, I fear to broke them again.

 

[jackluke]

This fix could be useful also for me to fix usb and mouse on Mac mini 2010?

No, for that you need to kmutil the LegacyUSBInjector.kext making a new snapshot with updated BKE , otherwise you could try to boot through USBopencore with CMD+S and exit .

 

[Alex-Microsmeta]

No, for that you need to kmutil the LegacyUSBInjector.kext making a new snapshot with updated BKE , otherwise you could try to boot through USBopencore with CMD+S and exit .

OK, I wait future developments

 

[air.man]

Before run the script, you need to plug the "USB Install macOS Big Sur Beta" (BaseSystem b9 legacy USB fix and fix2) because from there the patched BaseSystem is copied, it also makes a BaseSystembackup.dmg .

I wrote a condition on this new stage2 script that require also that BaseSystembackup, you can check from terminal with: ls /Volumes/*/BaseSystem/BaseSystembackup.dmg

After the patch you should notice in that "macOS Install Data" folder a new BaseSystem size 620 MB (from your picture the BaseSystem 661 MB is still the stock beta 9 incompatible with Legacy USB) and in "Locked Files" a BKE (prelinkedkernel) size of 25 MB (while the stock beta 9 one is 65 MB).

There was an issue on the script about unlock the "Locked Files", just fixed so redownload (updated also on previous post): BigSur BaseSystem stage2 installer fix.zip

Well, the stage2 completed. Unluckily can't reboot to BigSur, even with Opencore4s1 that shows the "macOS Installer" yet. The listing of CMD+S is the same as before. But the BigSur volume is changed as in pictures.

 

[jackluke]

Well, the stage2 completed. Unluckily can't reboot to BigSur, even with Opencore4s1 that shows the "macOS Installer" yet. The listing of CMD+S is the same as before. But the BigSur volume is changed as in pictures.

View attachment 964209 View attachment 964210 View attachment 964212

From those pictures installation completed, the boot folder x86_64SURamDisk.dmg is the stage3 installer (for this can't apply a legacy USB fix), that makes seal and system snapshot, but I often manually skip it booting directly targeting the "BigSur Data Volume", skipping stage3 also allows "sudo mount -uw /" (or mount -uw / from single user mode).

To clear the "macOS Installer" and maybe show the "BigSur Data" at apple startup manager, I can manually fix the Preboot, but first needed from Catalina terminal:

diskutil list | grep "Preboot"
And mount the largest "MegaBytes" Preboot Volume: diskutil mount diskXsY

then post the output of this copy paste on Catalina terminal:

ls /Volumes/Preboot/ ; ls /Volumes/Preboot/*/boot/System/Library/KernelCollections/ ; ls /Volumes/Preboot/*/System/Library/CoreServices/

 

[air.man]

From those pictures installation completed, the boot folder x86_64SURamDisk.dmg is the stage3 installer (for this can't apply a legacy USB fix), that makes seal and system snapshot, but I often manually skip it booting directly targeting the "BigSur Data Volume", skipping stage3 also allows "sudo mount -uw /" (or mount -uw / from single user mode).

To clear the "macOS Installer" and maybe show the "BigSur Data" at apple startup manager, I can manually fix the Preboot, but first needed from Catalina terminal:

diskutil list | grep "Preboot"
And mount the largest "MegaBytes" Preboot Volume: diskutil mount diskXsY

then post the output of this copy paste on Catalina terminal:

ls /Volumes/Preboot/ ; ls /Volumes/Preboot/*/boot/System/Library/KernelCollections/ ; ls /Volumes/Preboot/*/System/Library/CoreServices/

This is

nando@Nandos-MacBook ~ % diskutil list | grep "Preboot"
   2:                APFS Volume Preboot                 83.8 MB    disk1s2
   2:                APFS Volume Preboot                 141.7 MB   disk5s2
nando@Nandos-MacBook ~ % diskutil mount disk5s2
Volume Preboot on disk5s2 mounted
nando@Nandos-MacBook ~ % ls /Volumes/Preboot/ ; ls /Volumes/Preboot/*/boot/System/Library/KernelCollections/ ; ls /Volumes/Preboot/*/System/Library/CoreServices/
5AAC5794-DBA2-4A2A-881B-0762FA45D829
zsh: no matches found: /Volumes/Preboot/*/boot/System/Library/KernelCollections/
PlatformSupport.plist    SystemVersion.plist

 

[jackluke]

This is

nando@Nandos-MacBook ~ % diskutil list | grep "Preboot"
   2:                APFS Volume Preboot                 83.8 MB    disk1s2
   2:                APFS Volume Preboot                 141.7 MB   disk5s2
nando@Nandos-MacBook ~ % diskutil mount disk5s2
Volume Preboot on disk5s2 mounted
nando@Nandos-MacBook ~ % ls /Volumes/Preboot/ ; ls /Volumes/Preboot/*/boot/System/Library/KernelCollections/ ; ls /Volumes/Preboot/*/System/Library/CoreServices/
5AAC5794-DBA2-4A2A-881B-0762FA45D829
zsh: no matches found: /Volumes/Preboot/*/boot/System/Library/KernelCollections/
PlatformSupport.plist    SystemVersion.plist

So there is an almost empty BigSur Preboot folder, because the stage3 installer probably add files there, instead when updating an already installed BigSur can skip stage3 without issues, I could send some files to add there, but maybe try this copy paste from Catalina terminal:

sudo bless --folder /Volumes/BigSurHD/System/Library/CoreServices --bootefi /Volumes/BigSurHD/System/Library/CoreServices/boot.efi --label BigSur

reboot select USBopencore and try with CMD+S and exit .

If this don't worked then booting from the USB BigSur Installer (BaseSystem fixed), open terminal:
diskutil apfs updatePreboot /Volumes/BigSurHD/

edit:
You could even complete the stage3 installer plugging this external USB BigSur to a non legacy USB Mac .

 

[air.man]

So there is an almost empty BigSur Preboot folder, because the stage3 installer probably add files there, instead when updating an already installed BigSur can skip stage3 without issues, I could send some files to add there, but maybe try this copy paste from Catalina terminal:

sudo bless --folder /Volumes/BigSurHD/System/Library/CoreServices --bootefi /Volumes/BigSurHD/System/Library/CoreServices/boot.efi --label BigSur

reboot select USBopencore and try with CMD+S and exit .

If this don't worked then booting from the USB BigSur Installer (BaseSystem fixed), open terminal:
diskutil apfs updatePreboot /Volumes/BigSurHD/

edit:
You could even complete the stage3 installer plugging this external USB BigSur to a non legacy USB Mac .

Nope.
Even sudo bless.. and diskutil apfs.. didn't work (forbidden sign and same CMD+S output.
Maybe later I'll try to complete the installation on MBP8,2.
Anyway you are a real guru. Thanks a lot!

 

[jackluke]

Nope.
Even sudo bless.. and diskutil apfs.. didn't work (forbidden sign and same CMD+S output.
Maybe later I'll try to complete the installation on MBP8,2.
Anyway you are a real guru. Thanks a lot!

To boot BigSur Preboot you need mainly to add these files in these paths:

/Volumes/Preboot/UUIDBigSur/System/Library/CoreServices/boot.efi
/Volumes/Preboot/UUIDBigSur/boot/System/Library/KernelCollections/BootKernelExtensions.kc

the boot.efi can be copied from here /Volumes/BigSurHD/System/Library/CoreServices/

the BKE from here /Volumes/BigSurHD/System/Library/KernelCollections/BootKernelExtensions.kc

later I'll attach my beta 9 patched BKE that should allow at least to boot the CMD+S with legacy USB.

here is attached: BKE b9 patched

If you had installed BigSur on internal SATA disk these steps are not needed.

edit:
From USBopencore try to boot the BigSur Recovery (not the USB Installer) with CMD+S .
To boot Recovery allow on blank screen till 5 minutes , then on verbose lines type exit to continue booting.

From BigSur Recovery try this:

mount -uw /Volumes/BigSurHD
diskutil apfs updatePreboot /Volumes/BigSurHD
kmutil install --update-all
kcditto

 

[Romskie]

Well, well, well: The zoom issue has long been solved under Mojave & Catalina (there´s a patch for that). So, not useless at all... ;-)

how?

 

[air.man]

Deleted

 

[air.man]

To boot BigSur Preboot you need mainly to add these files in these paths:

/Volumes/Preboot/UUIDBigSur/System/Library/CoreServices/boot.efi
/Volumes/Preboot/UUIDBigSur/boot/System/Library/KernelCollections/BootKernelExtensions.kc

the boot.efi can be copied from here /Volumes/BigSurHD/System/Library/CoreServices/

the BKE from here /Volumes/BigSurHD/System/Library/KernelCollections/BootKernelExtensions.kc

later I'll attach my beta 9 patched BKE that should allow at least to boot the CMD+S with legacy USB.

If you had installed BigSur on internal SATA disk these steps are not needed.

edit:
From USBopencore try to boot the BigSur Recovery (not the USB Installer) with CMD+S .
To boot Recovery allow on blank screen till 5 minutes , then on verbose lines type exit to continue booting.

From BigSur Recovery try this:

mount -uw /Volumes/BigSurHD
diskutil apfs updatePreboot /Volumes/BigSurHD
kmutil install --update-all
kcditto

Well, at this point in time I have two recoveries... both blink the BigSurHD drive for a while and turn back to the boot screen.
Maybe it's time for a fresh new installation...

 

[justperry]

No new beta this week...?

Snip.../snip

FYI, better Edit the post you posted just before...the deleted one...instead of making a new one, no big deal, just a remark.

 

[MacHacJac]

@jackluke I just changed my HD3000 Mojave kexts using your method to 2048mb on my 2011 MBP. Does this have any affect on performance or is it just a joke?
Also, is there this kind of a hack for the CPU, or only the GPU? I kinda wanna spoof my Sandy Bridge Core i5 too...
I'm just curious. I've never "added" VRAM before

 

[Alex-Microsmeta]

Nope.
Even sudo bless.. and diskutil apfs.. didn't work (forbidden sign and same CMD+S output.
Maybe later I'll try to complete the installation on MBP8,2.
Anyway you are a real guru. Thanks a lot!

Here we find the best mac ethical hackers in the World

 

[jackluke]

Well, at this point in time I have two recoveries... both blink the BigSurHD drive for a while and turn back to the boot screen.
Maybe it's time for a fresh new installation...

View attachment 964284

Go on Catalina, plug the USB BigSur Installer, open Catalina terminal:

diskutil list

locate your BigSur Recovery (from your previous pictures should be on disk5s3)

diskutil mount disk5s3

cd /Volumes/*/BaseSystem/

sudo cp -a BaseSystembackup.dmg /Volumes/Recovery/5AAC5794-DBA2-4A2A-881B-0762FA45D829/BaseSystem.dmg


reboot with USBOpenCore and BigSur Recovery should work with CMD+S on the MacBook5,1 .

Anyway your issue is simply the Preboot, just adding boot.efi and BootKernelExtensions.kc should work.

 

[jackluke]

@jackluke I just changed my HD3000 Mojave kexts using your method to 2048mb on my 2011 MBP. Does this have any affect on performance or is it just a joke?
Also, is there this kind of a hack for the CPU, or only the GPU? I kinda wanna spoof my Sandy Bridge Core i5 too...
I'm just curious. I've never "added" VRAM before

It should improve the UI and graphics allocation to some apps, there are also CPU spoofing but imply opencore advanced ACPI patching on IOPlatformPluginFamily.kext that I don't know, on this other thread they made more advanced opencore config: https://forums.macrumors.com/threads/opencore-on-the-mac-pro.2207814/post-28644718

Also some frameworks editing: /System/Library/PrivateFrameworks/AppleSystemInfo.framework/Versions/A/Resources/en.lproj/Processors.strings