Open Richy-Z opened 8 months ago
My embedded USB controller brokes if I enable VT-D. I'll try to fix this by DMAR guide. So in some systems it looks problematic. UPDATED: DMAR guide doesn't help guide. My motherboard (asrock z170 extreme4) USB controller is not working. Luckily I have addidional pci-e one. I'm in doubt what causes that
Yes, my hardware become faulty (asrock z170 extreme4), when appleVTD is enabled.
Guide(s) in question: Dortania OpenCore Install Guide, specifically every config.plist guide
Since macOS Big Sur, Apple has added support for VT for Directed I/O (VT-d) and Kernel DMA Protection, allowing for extended Thunderbolt functionality and security. In fact, enabling VT-d is a requirement on macOS Ventura and up in order to fully enable network adapters which include built-in adapters and PCIe ones.
What is problematic however is the fact that all of the config.plist guides explicitly state that VT-d should be turned off, with no mention that this is only required for macOS < 11.
Apple states that VT-d is supported:
https://support.apple.com/en-gb/guide/security/seca4960c2b5/web
elitemacx86 posts:
https://elitemacx86.com/threads/how-to-enable-apple-vtd-on-macos-clover-opencore.868/
https://elitemacx86.com/threads/common-problems-in-macos-ventura-13-0.924/
Therefore:
DisableIoMapper
should only be used on macOS <11 (Big Sur) where VT-d cannot be disabled