# OpenCore Debugging

  • Supported version: 0.6.1

Needing to figure out why you're getting issues or stalling? Well, you've come to the right place:

# File Swaps

To start, make sure you're using either the DEBUG or NOOPT versions of OpenCore. This will provide much more info than the RELEASE version, the specific files that need to be swapped:

  • EFI/BOOT/
    • BOOTx64.efi
  • EFI/OC/Bootstrap/
    • Bootstrap.efi
  • EFI/OC/Drivers/
    • OpenRuntime.efi
    • OpenCanopy.efi(if you're using it)
  • EFI/OC/
    • OpenCore.efi

  • Note: Generally best to debug systems without OpenCanopy, if required make sure this file is from DEBUG else there will be virtually no debug information.

# Config Changes

Next, head to your config.plist and locate the Misc section, we have a couple entries we'll want to play with here:

# Misc

Here we'll want to enable the following:

  • AppleDebug: YES

    • Provides much more debugging information, specifically relating to boot.efi and will also store the log to disk.
  • ApplePanic: YES

    • This will allow kernel panics to be stored to disk, highly recommend keeping keepsyms=1 in boot-args to preserve as much info as possible.
  • DisableWatchdog: YES

    • Disables the UEFI watchdog, used for when OpenCore is stalling on something non-critical.
  • Target: 67(or calculate one below)

    • Used for enabling different levels of debugging
Value Comment
0x01 Enable Logging
0x02 Enable Onscreen debug
0x04 Enable logging to Data Hub.
0x08 Enable serial port logging.
0x10 Enable UEFI variable logging.
0x20 Enable non-volatile UEFI variable logging.
0x40 Enable logging to file.

To calculate the target, we can use a HEX calculator and then convert it to decimal. For us we want to have our values on stored onto a .txt file for later viewing:

  • 0x01 — Enable Logging
  • 0x02 — Enable Onscreen debug
    • Note this can heavily increase boot times on firmwares with poor GOP implementations
  • 0x10 — Enable UEFI variable logging.
  • 0x40 — Enable logging to file.

0x01 + 0x02 + 0x10 + 0x40 = 0x53

0x53 converted to decimal becomes 83

So we can set Misc -> Debug -> Target -> 83

  • DisplayLevel: 2147483714(or calculate one below)
    • Used for setting what is logged
Value Comment
0x00000002 DEBUG_WARN in DEBUG, NOOPT, RELEASE.
0x00000040 DEBUG_INFO in DEBUG, NOOPT.
0x00400000 DEBUG_VERBOSE in custom builds.
0x80000000 DEBUG_ERROR in DEBUG, NOOPT, RELEASE.

A full list can be found in DebugLib.h.

For us we just want the following:

  • 0x00000002 — DEBUG_WARN in DEBUG, NOOPT, RELEASE.
  • 0x00000040 — DEBUG_INFO in DEBUG, NOOPT.
  • 0x80000000 — DEBUG_ERROR in DEBUG, NOOPT, RELEASE.

Just like with Target, we use a HEX calculator then convert to decimal:

0x80000042 Converted to decimal Misc -> Debug -> DisplayLevel -> 2147483714

Once done, your config.plist should look like this:

# Disabling all logging

To remove all file logging, and debug messages, simply swap out all your OpenCore files for those in RELEASE like we did before in File Swap section.

Lastly, to remove writing to disk set the following:

  • AppleDebug = 0
  • ApplePanic = 0
  • Target = 0