macOS 11 Big Sur on Unsupported Macs Thread

[jhowarth]

On my BigSur beta 2 (sealed snapshot), I tried to use this @ASentientBot method to delete the annoying BigSur snapshots (the purpose is to use "sudo mount -uw /" in normal booting)

csrutil authenticated-root already disabled , tried either from a BigSur recovery or normal booting:

cd /S*/L*/F*/apfs.fs/C*/R*/

./apfs_systemsnapshot -v "/Volumes/mountpoint/BigSur/" -r ""

-r "" should tag no snapshots booting directly the unsealed BigSur System

But I can't tag it, system says:

Attempting tagging of snapshot on volume: /Volumes/BigSur
fs_snapshot_root: Operation not permitted
fs_snapshot_root failed with /Volumes/BigSur

While from BigSur beta 1 (I can use "sudo mount -uw /"), I am able to remove snapshots in this way:

tmutil listlocalsnapshots /Volumes/BigSur/

tmutil deletelocalsnapshots /Volumes/BigSur/ snapshotdatetime

That is fine for now. Just use your BigSur beta 1 installation pruned of snapshots to recreate a "legacy USB prelinkedkernel" where IOUSBHostFamily.kext is fully patched using IOUSBHostFamily-Infos.patch.zip and LegacyUSBInjector.kext removed prior to 'sudo kextcache -i /'. This will at least allow us to determine that the patched IOUSBHostFamily.kext works as a substitute on Big Sur. If that is the case, it will be worth exploring further what is going on with the chroot building of prelinkedkernels under a mounted snapshot.

 

[hvds]

Success with prelinkedkernel fix4 beta1 also here on MBP5,2: Ethernet works now!
Internal audio not yet, I'll follow your advice to remove AppleHDA.kext.

Thanks jackluke!

On MBP5,2 made a clean install of Beta2 following the prelinkedkernel route like for Beta1. Migration assistent to take everything possible over from my production 10.15.5supp, to make tests meaningful to my usage of the system. Wifi, ethernet and internal audio finally working (details of installation below).

MBP5,2 is a mid 2009 "legacy USB" Penryn machine with non-metal GPU.

Music and Mail working well, Photos (6.0) crashing after it had finished updating the library (log attached). Everything slow of course without acceleration, but good enough for testing.
Thanks jackluke (also for advice in private conversation) and ASentientBot!


- Erased an ssd as apfs, put it on internal sata connector, Catalina production disk on USB
- disabled authorized-root from terminal of bootable USB installer for Catalina/1.4.4, and set nvram boot-args to -no_compat_check amfi_get_out_of_my_way=1
- using 9600M GT GPU as I always do
- ran Hax3.app to start installation
- after installation applied prelinkedkernel fix4
- BigSur boots fine with wifi and ethernet available (no internal audio yet), do rest of setup
- did changes according to post #1781 but no internal audio yet (not important for me)
- migrate "all" (applications, user accounts, settings...) from Catalina with migration assistant
-- when migration ended, can't click the finish button as trackpad and keyboard now non-responsive (both on USB)
-- also wifi and ethernet unavailable
-- re-applied prelinkedkernel fix4 from Catalina
-- booted back to BS where migration can now be finished
- wifi and ethernet working, AND internal audio (not clear to my why)
- swapped disks back, so BS in on USB now.

Continued testing...

 

[jackluke]

That is fine for now. Just use your BigSur beta 1 installation pruned of snapshots to recreate a "legacy USB prelinkedkernel" where IOUSBHostFamily.kext is fully patched using IOUSBHostFamily-Infos.patch.zip and LegacyUSBInjector.kext removed prior to 'sudo kextcache -i /'. This will at least allow us to determine that the patched IOUSBHostFamily.kext works as a substitute on Big Sur. If that is the case, it will be worth exploring further what is going on with the chroot building of prelinkedkernels under a mounted snapshot.

Already tried doesn't worked, if replacing the SLE IOUSBHostFamily Info.plist prior, then boot but with CMD+S and "exit" .

It only prelinked "correctly" with kmutil BootKernelCollections.kc, but the stock SLE IOUSBHostFamily Info.plist needs to replace before making the KernelCollections, otherwise no boot to the loginUI, and CMD+S and "exit" is still required otherwise no usb input output devices.

 

[jhowarth]

Already tried doesn't worked, if replacing the SLE IOUSBHostFamily Info.plist prior, then boot but with CMD+S and "exit" .

It only prelinked "correctly" with kmutil BootKernelCollections.kc, but the stock SLE IOUSBHostFamily Info.plist needs to replace before making the KernelCollections, otherwise no boot to the loginUI, and CMD+S and "exit" is still required otherwise no usb input output devices.

Was that with both IOUSBHostFamily.kext/Contents/Info.plist and IOUSBHostFamily.kext/Contents/PlugIns/AppleUSBHostPlatformProperties.kext/Contents/Info.plist patched? The original proposed patch only patched IOUSBHostFamily.kext/Contents/Info.plist. The copy of the patch that I posted at IOUSBHostFamily-Infos.patch.zip does both files. It might be worth repeating that to double check that you did indeed capture both files in the patching.

If it is really failing, yet LegacyUSBInjector.kext works, it might be worth looking at whether patching IOUSBHostFamily.kext is tripping on some kext integrity check in Big Sur on that Info.plist file being changed. Also, is there any logging going on into system.log during the failing boots where legacy usb doesn't work? Perhaps there are some clues there.

ps When you get failing legacy usb, how does it appear? In my case, on an external usb drive, it always shows up as a Bluetooth keyboard dialog appearing because a usb keyboard couldn't be found. The logic here is rather baffling because if it really can't find a usb keyboard, how did it ever manage to have the legacy usb support in the rebuilt prelinkedkernel to boot from a usb drive in the first place? Bizarre.

Update: When building the prelinkedkernel under snapshots on Big Sur with the IOUSBHostFamily-Infos.patch.zip changes that work under Catalina applied, I see the same Bluetooth keyboard dialog. So far the only messages associated with usb loading at this point in system.log are...

Jul 11 14:21:42 Jacks-MacBook-Pro com.apple.xpc.launchd[1] (com.apple.driverkit.AppleUserUSBHostHIDDevice0-(0x10000044f)[319]): Service exited due to SIGILL | sent by exc handler[319]
Jul 11 14:21:42 Jacks-MacBook-Pro com.apple.xpc.launchd[1] (com.apple.driverkit.AppleUserUSBHostHIDDeviceKB-(0x100000466)[325]): Service exited due to SIGILL | sent by exc handler[325]
Jul 11 14:21:42 Jacks-MacBook-Pro com.apple.xpc.launchd[1] (com.apple.driverkit.AppleUserUSBHostHIDDevice1-(0x100000454)[322]): Service exited due to SIGILL | sent by exc handler[322]
Jul 11 14:21:42 Jacks-MacBook-Pro com.apple.xpc.launchd[1] (com.apple.driverkit.AppleUserUSBHostHIDDevice1-(0x10000046a)[330]): Service exited due to SIGILL | sent by exc handler[330]
Jul 11 14:21:42 Jacks-MacBook-Pro com.apple.xpc.launchd[1] (com.apple.driverkit.AppleUserUSBHostHIDDevice0-(0x1000004d5)[331]): Service exited due to SIGILL | sent by exc handler[331]
Jul 11 14:21:42 Jacks-MacBook-Pro com.apple.xpc.launchd[1] (com.apple.driverkit.AppleUserUSBHostHIDDevice1-(0x1000004d7)[332]): Service exited due to SIGILL | sent by exc handler[332]
Jul 11 14:21:42 Jacks-MacBook-Pro com.apple.xpc.launchd[1] (com.apple.driverkit.AppleUserUSBHostHIDDeviceKB-(0x1000004da)[333]): Service exited due to SIGILL | sent by exc handler[333]
Jul 11 14:21:42 Jacks-MacBook-Pro com.apple.xpc.launchd[1] (com.apple.driverkit.AppleUserUSBHostHIDDevice1-(0x1000004dc)[334]): Service exited due to SIGILL | sent by exc handler[334]

The interesting thing here is that the failures are in the usb Driverkit drivers and usb is the only kext which had associated Driverkit drivers added. So perhaps legacy prelinked kernels don't know how to interact with the Driverkit drivers compared to kc's. However that still begs the question how jackluke ever got a prelinkedkernel built with legacy usb support. Did beta 1 not have those Driverkit drivers wired in yet?

 

[abelpinate]

I don't notice any difference between Beta 1 and Beta 2, but I like to be in Beta 2. Hopefully Beta 3 will come out soon to reinstall everything from 0. ?

I install the Betas on my main computer and without partitions. "A lo loco se vive mejor"

Chamo, pero a mi me da miedo! I'm doing a work for a client right now... y me da miedo que no pueda instalar el AutoCAD...

As far, your clarifications has given to me a lot of esperancita mijo.... HAHAHA

 

[slears]

Any chance somebody can help with this? Camera is working fine as I can see myself in photo booth but the likes of Zoom, Teams etc will not allow me to add them in Privacy settings to use the camera and mic??

 

[GSXB]

to invoid error 66
11a install 3 min screen (takes a little bit longer)
12. reboot about 32 min screen install
13. reboot wait install up to the mid of the apple logo
14. press power button to shut down the computer
15. press option key to select the visible BigSur volume -not the install volume
16. several reboots - select always the BigSir volume
17. install finished
18. no error 66 - sudo mount -uw / now works and BigSur volume is visible
19. install wifi kext
This is what the youtube video shows.

ive used the same method how did you get the internal sound working

 

[LuisN]

Very much appreciated! Thanks!

As far as upgrading my WiFi adapter, is there a list of supported components? Are they not of a proprietary socket (and/or is there a common selection of models that will work that are also found in other PCs)? Or am I buying an OEM (compatible) part from a newer 13" MacBook Pro/MacBook Air/15" MacBook Pro that happens to fit with the same connectors? Also, once I upgrade the WiFi adapter, will the Big Sur installer simply recognize my Mac as being compatible?

Apologies for all of the questions. And again, thanks for the info!

I bought this one:

Broadcom wireless card bcm94360cs2 653-0020 for apple macbook air a1465 tested | eBay

Find many great new & used options and get the best deals for Broadcom wireless card bcm94360cs2 653-0020 for apple macbook air a1465 tested at the best online prices at eBay! Free shipping for many products!

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It works OOB in macbook pro retina 2012-2013 maybe up to 2015?

 

[PBiscaia]

Yes, on a non-APFS or legacy usb Mac, you should install BigSur on internal SATA disk (it requires 50 GB), and you need the 9,56 GB "Install macOS Big Sur Beta.app" (to copy on Catalina /Applications/ ) and this tool to install directly from Catalina desktop: https://forums.macrumors.com/thread...unsupported-macs-thread.2242172/post-28619108

after installation to make work usb devices (and wifi), you should apply this from Catalina: https://forums.macrumors.com/thread...unsupported-macs-thread.2242172/post-28643133

Finally, managed to install Beta 2 on my Imac 10,1 with the precious help from jackluke, thanks.
It is not perfect yet, not working sound, wifi, and transparency.
After install applied your beta patch, should apply the other or not?
Help is welcome, thank you all!

 

[jhowarth]

On my BigSur beta 2 (sealed snapshot), I tried to use this @ASentientBot method to delete the annoying BigSur snapshots (the purpose is to use "sudo mount -uw /" in normal booting)

csrutil authenticated-root already disabled , tried either from a BigSur recovery or normal booting:

cd /S*/L*/F*/apfs.fs/C*/R*/

./apfs_systemsnapshot -v "/Volumes/mountpoint/BigSur/" -r ""

-r "" should tag no snapshots booting directly the unsealed BigSur System

But I can't tag it, system says:

Attempting tagging of snapshot on volume: /Volumes/BigSur
fs_snapshot_root: Operation not permitted
fs_snapshot_root failed with /Volumes/BigSur

While from BigSur beta 1 (I can use "sudo mount -uw /"), I am able to remove snapshots in this way:

tmutil listlocalsnapshots /Volumes/BigSur/

tmutil deleteLocalSnapshots /Volumes/BigSur/ snapshotdatetime

Setting aside the legacy usb issues for a moment, can you please test this approach on a machine that doesn't need legacy usb but has Big Sur installed with a snapshot present?

Disable authenticated-root in nvram using csrutil from Big Sur from the root level of a patched Catalina usb installer with..

sudo csrutil2 authenticated-csr disable

Also make sure to set...

sudo nvram boot-args="-no_compat_check"

Install Big Sur on an external drive from a supported machine. Attach this drive under Catalina mount it's Preboot volume.

cd /Volumes/Preboot/*/System/Library/CoreServices/
curl https://github.com/jacklukem/BigSurfixes/raw/master/prelinkedkernel%20fix/com.apple.Boot.plist --progress-bar -L -o /private/tmp/com.apple.Boot.plist
sudo cp -a /private/tmp/com.apple.Boot.plist .
curl "https://raw.githubusercontent.com/jacklukem/BigSurfixes/master/legacy%20usb%20prelinkedkernel%20beta1/prelinkedkernel?raw=true" --progress-bar -L -o /private/tmp/prelinkedkernel
sudo mv PlatformSupport.plist PlatformSupport.plist2
sudo cp -a /private/tmp/com.apple.Boot.plist .
cd ../PrelinkedKernels
sudo cp -a /private/tmp/prelinkedkernel .

place telemetrap.kext v0.22 on a usb memory stick name Untitled

reboot under Big Sur volume and execute the commands below adjusted for your partition numbers

**************************************************

mkdir /tmp/mntpoint
sudo mount -o nobrowse -t apfs /dev/disk7s5 /tmp/mntpoint

cd /tmp/mntpoint/Library/Extensions
sudo ditto /Volumes/Untitled/telemetrap.kext telemetrap.kext
sudo chmod -R 755 telemetrap.kext
sudo chown -R root:wheel telemetrap.kext

*** commands to rebuild new prelinkedkernel and copy to /System/Volumes/Preboot/*/System/Library/PrelinkedKernels ***

*** add missing PrelinkedKernels directory as symlink using relative path to /Library/Apple/System/Library directory ***
sudo ln -s ../../../../System/Library/PrelinkedKernels /tmp/mntpoint/Library/Apple/System/Library/PrelinkedKernels

*** Catalina has no /Library/Apple/System/Library/Caches but only /Library/Caches with no kernel caches ***
*** Catalina stores kernel caches in /System/Library/Caches ***
*** add missing Caches as symlink using relative path to /System/Library/Caches in mounted snapshot ***
sudo ln -s ../../../../System/Library/Caches /tmp/mntpoint/Library/Apple/System/Library/Caches

sudo chroot /tmp/mntpoint mount -uw /

sudo touch /tmp/mntpoint/Library/Extensions/

sudo chroot /tmp/mntpoint kextcache -i /

cd /System/Volumes/Preboot/*/System/Library/PrelinkedKernels
sudo cp /tmp/mntpoint/System/Library/PrelinkedKernels/prelinkedkernel .

cd ~
sudo bless --folder /tmp/mntpoint/System/Library/CoreServices --bootefi --create-snapshot

*** reboot to make modified snapshot active root ***

This approach may very well produce a usable kernel on machines that don't require the legacy usb changes. Please try it out.

 

[TimothyR734]

Is there a way to fix kext signature Validation error code 67054 as I replaced the IO80211Family.kext from /System/Library/Extensions moved to /Library/Extensions install this from here https://developer.apple.com/library/archive/technotes/tn2318/_index.html

 

[jhowarth]

Is there a way to fix kext signature Validation error code 67054 as I replaced the IO80211Family.kext from /System/Library/Extensions moved to /Library/Extensions install this from here https://developer.apple.com/library/archive/technotes/tn2318/_index.html

On my MacPro 3,1, the Big Sur copy of IO80211Family.kext loads in S/L/E loads in favor over that in L/E. I directly replaced the copy in S/L/E with one from Catalina...

mkdir /tmp/mntpoint
sudo mount -o nobrowse -t apfs /dev/disk7s5 /tmp/mntpoint
cd /tmp/mntpoint/System/Library/Extensions
sudo rm -fr IO80211Family.kext
sudo ditto /Volumes/Untitled/IO80211Family.kext IO80211Family.kext
sudo chmod -R 755 IO80211Family.kext
sudo chown -R root:wheel IO80211Family.kext
cd ~
sudo bless --folder /tmp/mntpoint/System/Library/CoreServices --bootefi --create-snapshot

After rebooting, under the same jakeluke legacy usb prelinkedkernel, System Profiler then showed wifi networks whereas it hadn't under the Big Sur copy. Connecting to wifi is a tad glitchy at this point. The wifi menu controls won't display those available networks so I entered the SSID and wifi password manually. At this point, it will say that it can't connect but if you logout of your account and log back in, it will automatically connect to that network. Furthermore, from that point on, the wifi networks will appear in the GUI scan. I suspect this is a glitch from installing on a supported machine and moving the drive to an unsupported one.

 

[TimothyR734]

On my MacPro 3,1, the Big Sur copy of IO80211Family.kext loads in S/L/E loads in favor over that in L/E. I directly replaced the copy in S/L/E with one from Catalina...

mkdir /tmp/mntpoint
sudo mount -o nobrowse -t apfs /dev/disk7s5 /tmp/mntpoint
cd /tmp/mntpoint/System/Library/Extensions
sudo rm -fr IO80211Family.kext
sudo ditto /Volumes/Untitled/IO80211Family.kext IO80211Family.kext
sudo chmod -R 755 IO80211Family.kext
sudo chown -R root:wheel IO80211Family.kext
cd ~
sudo bless --folder /tmp/mntpoint/System/Library/CoreServices --bootefi --create-snapshot

After rebooting, under the same jakeluke legacy usb prelinkedkernel, System Profiler then showed wifi networks whereas it hadn't under the Big Sur copy. Connecting to wifi is a tad glitchy at this point. The wifi menu controls won't display those available networks so I entered the SSID and wifi password manually. At this point, it will say that it can't connect but if you logout of your account and log back in, it will automatically connect to that network. Furthermore, from that point on, the wifi networks will appear in the GUI scan. I suspect this is a glitch from installing on a supported machine and moving the drive to an unsupported one.

I tried replacing the the IO80211Family.kext and IO80211FamilyV2.kext from Catalina as it was a new version then the one in /System/Library/Extensions but no I get too/user permission error need to root:wheel

 

[jhowarth]

I tried replacing the the IO80211Family.kext and IO80211FamilyV2.kext from Catalina as it was a new version then the one in /System/Library/Extensions but no I get too/user permission error need to root:wheel

On a MacPro 3,1, only the IO80211Family.kext appears as loaded so there is no reason to replace the IO80211FamilyV2.kext copy.

Note that this behavior matches Catatlina Patcher which only downgrades IO80211Family.kext for its athandbcm and bcm4321 patch sets.

 

[CharlieRuiz97]

I have a question for all of you guys?... I wanna begin to learn swift to develop universal apps can I do it on Catalina or I need Big sur and beta xcode for that? (building Universal apps) cause my Mac is a 7,1 whitebook that doesn't run big sur yet so... Can I do swift development for universal apps on Catalina?... And another thing... At the beginning of the year I installed swift playgrounds to try learning swift but it didn't run the code and crashed, this is a problem because of the lack of metal compatible card on my Mac?

 

[Maclinux]

Chamo, pero a mi me da miedo! I'm doing a work for a client right now... y me da miedo que no pueda instalar el AutoCAD...

As far, your clarifications has given to me a lot of esperancita mijo.... HAHAHA

?????

 

[Barry K. Nathan]

I have a question for all of you guys?... I wanna begin to learn swift to develop universal apps can I do it on Catalina or I need Big sur and beta xcode for that? (building Universal apps) cause my Mac is a 7,1 whitebook that doesn't run big sur yet so... Can I do swift development for universal apps on Catalina?... And another thing... At the beginning of the year I installed swift playgrounds to try learning swift but it didn't run the code and crashed, this is a problem because of the lack of metal compatible card on my Mac?

Let's check the Xcode 12 for macOS Universal Apps release notes... It requires macOS Catalina 10.15.4 or higher, so Catalina should work. (Assuming it doesn't need Metal, of course.)

Regarding the Swift Playgrounds crash, that would be my first guess as well, but I don't know for sure.

 

[1404]

I seem to be stuck

managed to select language when re booting
I just get first image second image shows samsung Data, next icon is recovery 10:16. Progress bar stays where it is. used opencore 0.60

 

[TimothyR734]

I wonder if my fairly new ssd is starting to fail as I am getting mismatch errors when performing first aid after erasing the drive I have must have atlases partition/formatted the ssd 50 times and same with my usb flash drive in the last week trying to get my wifi working as I installed Catalina which I also have on my internal hdd and to bots faster than on the ssd after I installed apple updates reboot took 15 mins to boot up slow as a slug and the external ssd is the only one I have to test Big Sur on

 

[Yebubbleman]

I bought this one:

Broadcom wireless card bcm94360cs2 653-0020 for apple macbook air a1465 tested | eBay

Find many great new & used options and get the best deals for Broadcom wireless card bcm94360cs2 653-0020 for apple macbook air a1465 tested at the best online prices at eBay! Free shipping for many products!

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It works OOB in macbook pro retina 2012-2013 maybe up to 2015?

I do have one additional question:

The link you sent me to implied that future betas might break the WiFi driver and that I'll need to basically install the whole OS over the top of my existing installation rather than run an easy in-line package. Is there any way around doing this that you know of?

 

[nandor690]

I found a way to disable snapshots at install time. It's kind of impractical, but I'm guessing that this method may eventually be used in automated patchers.

First, a quick high-level recap of the install process:

1. The Install macOS Beta.app extracts its payload (including the installer BaseSystem, ramdisk, OS payload, boot files, and signature stuff) onto the target disk and makes it bootable.
2. The system reboots from that BaseSystem image, which extracts the main OS payload onto the system volume. It also copies the ramdisk to the data volume. It sets the ramdisk as the next boot target.
3. The ramdisk creates firmlinks and recovery partition, among other things. It snapshots the system volume, seals it, and tags the snapshot for boot.

In step #3, the snapshot creation and tagging as boot volume is done by /usr/libexec/ramrod/plugins/ramrod-macos-patchd-plugin.ramrod (a plugin that's loaded by /usr/libexec/ramrod/ramrod) on the ramdisk.

What I've done is patch this plugin to disable snapshot creation/tagging (sealing can already be disabled by a plist key or my Hax2 thingy). The two specific functions I targeted are:

-[LPAPFSVolume createSnapshot:error:]
-[LPAPFSVolume rootToSnapshot:error:]

And they are both just replaced by "return true":

mov rax,0x1
ret

The issue with modifying the ramdisk is that it's verified (based on checksums in a BOM file) by the BaseSystem, prior to copying it in step #2 above. It's verified again by the kernel (side note, this now treats auth-root-dmg and root-dmg exactly the same -- see imageboot.c).

I currently work around the first issue by holding down the alt key after step #2 completes, booting back into another OS, and then replacing the plugin in the ramdisk (/Volumes/* - Data/boot/x86_64SURamDisk.dmg) at this time, after the BaseSystem installer verifies it and right before it is booted. An automated patcher will probably have to tamper with BaseSystem to avoid this.

The second issue can be worked around by setting CSR_ALLOW_ANY_RECOVERY_OS, either with csrutil or (my personal favorite) the horrifying 0xffffffff boot.efi patch.

I know this is all very complex and not fun to do by hand. But personally, it beats having to struggle with unreliable commands to disable/delete snapshots afterwards. It might just be me, but I've still never gotten consistent results. And it's nice to not have to worry about "error 66" at all.

Patcher developers @dosdude1 @parrotgeek1 may find this useful. Or maybe not!

I hope they do because I can’t get your other method to work. I just want to be able to use mount -us / so I can run some commands to get handoff and continuity working. For some reason Iv had to do this since high Sierra.

 

[Alex-Microsmeta]

@hvds , @Alex-Microsmeta , @quaccOS and others who used my prelinkedkernel fix4 for Ethernet, Wifi (and legacy usb and telemetry plugin), since I recently on "BigSur beta2" encountered the sealed snapshot booting and got also prohibitory symbol on sound icon, I found an enough easy way to fix the Sound (internal speakers) and Mic .

For mount non-snapshot system and creating a new snapshot from BigSur credit to a twitter user Damien.

After installed "BigSur beta2" I noticed that I can't even rename my Volume Label, but I also renamed it through the mentioned method, instead the Preboot Volume is writable as also the BigSur Data Volume.

First requirement is this: nvram csr-active-config w%08%00%00 (or w%09%00%00 )
that is: "csrutil authenticated-root disable"

then in a similar way, as already wrote also from others, from a BigSur normal booting terminal:

sudo mkdir ~/Snapshot/

(this makes an empty folder mount point on your home folder so copy exactly as written)

mount

(on the first output "mount" line you can notice a diskXsYsZ you have to consider only diskXsY)

sudo mount -o nobrowse -t apfs /dev/diskXsY ~/Snapshot/

open ~/Snapshot/

(from Finder you can now rename your Volume Label, note from Finder the mount point has your BigSurLabel while from terminal it has the "Snapshot" folder name so the folder name must be used from BigSur terminal)

from Finder browse this:

System/Library/UserEventPlugins/com.apple.telemetry.plugin

(remove the com.apple.telemetry.plugin)

System/Library/Extensions/AppleHDA.kext

(replace AppleHDA.kext with this attached: HighSierra AppleHDA.kext.zip)

sudo chown -R 0:0 ~/Snapshot/System/Library/Extensions/

sudo chmod -R 755 ~/Snapshot/System/Library/Extensions/

sudo bless --folder ~/Snapshot/System/Library/CoreServices/ --bootefi --create-snapshot

tmutil localsnapshot

(check that the listed snapshot has the current date time)


Without rebuild any kextcache or kmutil at next reboot Sound internal speakers and Mic should work.

Edit: Ops! ? Something went wrong. Now BS crashes while booting, also using OpenCoreLoader3. I try to fix with fix2 and 3. Don't worry, It's normal while betatesting.

Finally, with BS csrutil authenticated-root DISABLED, I have executed this internal audio fix. It's incredible how easy is now to modify the system files!!! Thank you one more time from your best fan and betatester.

 

[TimothyR734]

[automerge]1594534017[/automerge]
this is as far as I have got to trying to get wifi working on my iMac 13,1 but my next issues when opened up Network in SYStem Preferences I only had Ethernet, Bluetooth and Thunderbold Bridge listed to I hooked umps old old Ethernet cable and plugged it to my router and iMac and use Migration Assistant to transfer Network setting from Catalina now I have WiFi listed but when open the Network settings where the turn WiFi on button is it says do not loc >> then below that 2 lines that say <<from localizable strings

 

[justperry]

View attachment 933122 View attachment 933123
[automerge]1594534017[/automerge]
this is as far as I have got to trying to get wifi working on my iMac 13,1 but my next issues when opened up Network in SYStem Preferences I only had Ethernet, Bluetooth and Thunderbold Bridge listed to I hooked umps old old Ethernet cable and plugged it to my router and iMac and use Migration Assistant to transfer Network setting from Catalina now I have WiFi listed but when open the Network settings where the turn WiFi on button is it says do not loc >> then below that 2 lines that say <<from localizable strings

They are both version 12.2b1, those don't work, those are the Big Sur kexts.

Why don't you try Barry K. Nathan way to install the kexts, it works flawlessly.

 

[TimothyR734]

They are both version 12.2b1, those don't work, those are the Big Sur kexts.

Why don't you try Barry K. Nathan way to install the kexts, it works flawlessly.

The IO1080211Family.Kext in /Library/Extensions is from Catalina when I reinstalled Big Sur this evening when I checked the /Library/Extensions folder it did not have a IO1080211Family.Kext at all so that's why I took the one from Catalina which I know works. And from what I was told to compare both IO80211Family.kexts the one in /System/Library/Extensions is 12.2b1 and so is the one from Catalina