dortania/OpenCore-Legacy-Patcher

PATA and macOS Monterey support

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#707 opened on Nov 7, 2021

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 (3 comments) (0 reactions) (0 assignees)Python (9,760 stars) (977 forks)batch import
back-endhelp wanted

Description

With macOS Monterey, the AppleIntelPIIXATA we use to restore PATA support broke. Because of this, numerous 2008 era Macs have lost support for their DVD drive when booted into Monterey.

Currently unknown where the issue lies, further investigation required.

Affected Models

  • MacBook4,1
  • MacBookPro4,1
  • iMac7,1
  • iMac8,1
  • MacPro3,1
  • Xserve2,1

Contributor guide

Tech stack
pythonc
Domain
toolinginfrastructure
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
5
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
over 1 week
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
needs investigation
Prerequisites
macOS kernel extension developmentC programmingPATA/IDE hardware knowledgekernel debugging skills
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
5
Research direction
The root cause of the PATA driver failure on macOS Monterey is unknown. Begin by reviewing the AppleIntelPIIXATA kext source code (if available) and comparing its behavior between macOS Big Sur and Monterey. Check for I/O Kit changes that may affect the driver's initialization. Examine system logs (kernel.log) for any panic or error messages related to the kext. Consider testing with different SATA/PATA configurations. Further investigation should focus on identifying the exact incompatibility in the kernel extension.