Ventura requires avx2 to be enabled

[MobCode100]

Hi, thank you the commitment maintaining this great project. I would like to make small changes to prevent others from having the same situation that I've had trying to install macOS Ventura. I'm unable to boot after normal installation following the README.md guide with errors relating to no dyld cache or library not found (e.g. libSystem.B.dylib):

It seems to be the problem of Apple dropping pre-Haswell support in macOS, that moves dyld to Preboot images OS.img according to this, and this. The dyld cache is only available for CPU with the avx2 instruction. An easy fix for this is to change -cpu Penryn to -cpu host and adding +avx2 to the MY_OPTIONS line in OpenCore-Boot.sh (if the host CPU supports it).

This PR only adds a note to the README file, should OpenCore-Boot script be modified?

[danwdart]

Can confirm this fixed the boot for me.

[kholia]

Thanks for the PR. I will commit the changes manually soon.

[kholia]

I will commit the changes manually soon.

Done and I have added you to the CREDITS.md file. Thanks again.

[ghost]

It should be noted that the +avx2 and -cpu host QEMU options of course do not work for host CPUs that do not support the AVX2 instruction natively, e. g., Intel pre-Haswell.

"OpenCore Install Guide" mentions that "[one] can use CryptexFixup to force [non-AVX2] dyld cache to be installed", but "Polaris [Radeon 500 series] GPUs remain unsupported on machines without AVX2". So, it is possible to boot macOS Ventura on a CPU without AVX2, but not use a Radeon 500 series GPU under QEMU with GPU pass-through.

Related resources: "macOS Ventura and OpenCore Legacy Patcher Support" and "Legacy Metal Graphics Support and macOS Ventura".

[MobCode100]

It should be noted that the +avx2 and -cpu host QEMU options of course do not work for host CPUs that do not support the AVX2 instruction natively, e.g., Intel pre-Haswell. This source mentions that "[one] can use CryptexFixup to force [non-AVX2] dyld cache to be installed", but "Polaris [Radeon 500 series] GPUs remain unsupported on machines without AVX2". So, it is possible to boot macOS Ventura on a CPU without AVX2, but not use a Radeon 500 series GPU under QEMU with GPU pass-through.

Great findings, so this should be noted in the readme file?

[ghost]

I would say it's probably not worth it, since the current state of macOS Ventura on non-AVX2 CPUs seems to be very hacky.

[crystall1nedev]

It should be noted that the +avx2 and -cpu host QEMU options of course do not work for host CPUs that do not support the AVX2 instruction natively, e. g., Intel pre-Haswell.

"OpenCore Install Guide" mentions that "[one] can use CryptexFixup to force [non-AVX2] dyld cache to be installed", but "Polaris [Radeon 500 series] GPUs remain unsupported on machines without AVX2". So, it is possible to boot macOS Ventura on a CPU without AVX2, but not use a Radeon 500 series GPU under QEMU with GPU pass-through.

Related resources: "macOS Ventura and OpenCore Legacy Patcher Support" and "Legacy Metal Graphics Support and macOS Ventura".

AMD driver issue applies to all AMD GPUs supported in Ventura. This means that not only is Radeon 500 series affected, but the entirety of the GCN4, GCN5, and supported Navi lines will not work.

[ghost]

FYI, it is possible to use GPU passthrough under macOS Ventura with pre-Haswell (non-AVX2) CPUs, see: #218.