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macOS boot.efi developer's thread
- Thread starter mikeboss
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Ok. New commit ready for testing. Check ioreg for board-id and that should be set to
Mac-F42C88C8. If that is correct, then try to download El Capitan from the App Store (fails for MacPro1,1 and MacPro2,1).
With BaseSystem.dmg method yes, with createinstallmedia I also changed sha1 for BaseSystem.dmg
commit e235aca . . .
build fails (VSE2015; Dell Precision T5500; Win 10):
"syntax error: ')' in BootArgs.cpp on line 363"
"syntax error: missing ';' before identifier 'DEVICE_TREE_NODE'."
Just got GitHub desktop installed, and your repository synch'd . . . successfully (I hope/see (that funny face on each commit does not do you justice, imo)).
I have limited screen-time, by virtue that I am in the field (literally (I am in the horticulture business by-day)), and my center of energy usually precludes, er, cerebral activities, such as compiling, code-analysis, and general computing (to say the least).
To make and install these 'boot.efi's is quite an effort; but, we do what we do, when we can do what we do
hth, Pike.
build fails (VSE2015; Dell Precision T5500; Win 10):
"syntax error: ')' in BootArgs.cpp on line 363"
"syntax error: missing ';' before identifier 'DEVICE_TREE_NODE'."
Just got GitHub desktop installed, and your repository synch'd . . . successfully (I hope/see (that funny face on each commit does not do you justice, imo)).
I have limited screen-time, by virtue that I am in the field (literally (I am in the horticulture business by-day)), and my center of energy usually precludes, er, cerebral activities, such as compiling, code-analysis, and general computing (to say the least).
To make and install these 'boot.efi's is quite an effort; but, we do what we do, when we can do what we do
hth, Pike.
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Faking board-id. Black boot.efi
WARNING: Line 363 of BootArgs.cpp rewritten as
DevTreeAddProperty(rootNode, CHAR8_CONST_STRING("board-id"), "Mac-F42C88C8", 13, FALSE);
WARNING: Line 363 of BootArgs.cpp rewritten as
DevTreeAddProperty(rootNode, CHAR8_CONST_STRING("board-id"), "Mac-F42C88C8", 13, FALSE);
I suppose faking the board ID doesn't have any real negative repercussions, other than some inaccurate Hardware Overview System Information, although that same inaccurate information will make the old Mac Pro pass as a supported machine, thereby making it unnecessary to modify mpkg and plist files in the Installer, as we've been doing these past years. I don't actually know if the creation of a stand-alone self-booting El Capitan installer would be necessary at all anymore, provided the regular unmodified installation app is launched from a boot.efi that ensures its own persistence. Would it be possible at all for boot.efi to copy itself to memory when the computer boots and then to rewrite itself (no matter what the SIP settings might be) from memory immediately before the computer is shut down or restarted?
If such a thing were achievable, we would still need occasional access to the system using a not-so-clever boot.efi so that boot.efi maintenance could be carried out if needed.
Edit: How about this scenario? The creation of a universal stand-alone self-booting El Capitan installer could still be mandatory, but it would only be modified by copying boot.efi in the two usual places (or three, if you will). When booting from the install media, that boot.efi wouldn't be persistence-hardened, but, at the end of its run, would see to it that two copies of itself were copied to the relevant folders of the target installation disk and to the usual place of the Recovery HD. Only when run from the normal El Capitan disk would boot.efi behave in a persistence-hardened way, i.e., rewriting itself at the end of each session. Would this be possible at all?
If such a thing were achievable, we would still need occasional access to the system using a not-so-clever boot.efi so that boot.efi maintenance could be carried out if needed.
Edit: How about this scenario? The creation of a universal stand-alone self-booting El Capitan installer could still be mandatory, but it would only be modified by copying boot.efi in the two usual places (or three, if you will). When booting from the install media, that boot.efi wouldn't be persistence-hardened, but, at the end of its run, would see to it that two copies of itself were copied to the relevant folders of the target installation disk and to the usual place of the Recovery HD. Only when run from the normal El Capitan disk would boot.efi behave in a persistence-hardened way, i.e., rewriting itself at the end of each session. Would this be possible at all?
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e235aca3956a2a766bb3dfba237d9d01b9cb801b
"ioreg -lp IOService | grep board-id" gave Mac-F4208DA9.
"ioreg -lp IOService | grep board-id" gave Mac-F4208DA9.
Right. board-id change not working. Will look into it.
Edit: Yeah I was expecting this. We need an SMBIOS patcher. Loads of work. Oh well. Let's have a stab at it.
Next. People with a created media USB stick should rename/backup /S(/L(/Prelinkedkernels/prelinkedkernel and try to boot from it. Double check that the file wash;t recreated. Need a confirmation that this actually works. Thanks!
Edit: Yeah I was expecting this. We need an SMBIOS patcher. Loads of work. Oh well. Let's have a stab at it.
Next. People with a created media USB stick should rename/backup /S(/L(/Prelinkedkernels/prelinkedkernel and try to boot from it. Double check that the file wash;t recreated. Need a confirmation that this actually works. Thanks!
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Pike, I suppose you aren't really interested in the manually-created install media following Hennesie2000's guide. In case you are, however, I can mention that, in my case, the /S(/L(/Prelinkedkernels/prelinkedkernel hasn't been recreated (its date is 17 September, 8:37. Its size is 18,915,592 bytes. The boot.efi of my installer is the black repository version.
Any media that can be used to boot a Mac, even the installer, is fine. As long as these:
/System/Library/Caches/com.apple.kext.caches/Startup/kernelcache
/System/Library/Prelinkedkernels/prelinkedkernel
are renamed.
Renamed? Which name should they have? Mine are called exactly that way.
PS Actually, my installer doesn't have /System/Library/Caches/com.apple.kext.caches, just an empty /System/Library/Caches/com.apple.CVMS folder.
PS Actually, my installer doesn't have /System/Library/Caches/com.apple.kext.caches, just an empty /System/Library/Caches/com.apple.CVMS folder.
'prelinkedkernel' is found in /Volumes/Image Volume/.IABootFiles only (via terminal, while in the Installer environment).
with commit e235aca
# ioreg -lp IOService | grep board-id gives
"Mac-F4208DC8"
with commit e235aca
# ioreg -lp IOService | grep board-id gives
"Mac-F4208DC8"
tested with e235aca3956a2a766bb3dfba237d9d01b9cb801b
on USB installer media with /System/Library/Caches/com.apple.kext.caches/Startup/kernelcache
renamed "kernelcache" to "WAS_kernelcache" and the system booted just fine into the installer's GUI.
the file was NOT recreated during boot.
Interesting. It failed for Mike. Did you try to download El Capitan from the App Store?
Edit: Sorry. Misinterpreted the board-id. But without the kernel cache and prelinkedkernel it boots. That is fine.
Oops. My mistake (see edit).
Anyway. I guess that we can rule out the problem of not having a prelinkedkernel, because it boots just fine without this file. Thanks to the kernel patching.
New commit available for compilation. Only use this on USB (installer) media to test if it boots. It will most likely fail (YOU ARE WARNED).
Look for the new debug output:
"PIKE: SMBIOS table found!" (5x)
"PIKE: SMBIOS table replaced!"(5x)
Look for the new debug output:
"PIKE: SMBIOS table found!" (5x)
"PIKE: SMBIOS table replaced!"(5x)
c56a6ae54b3c191eaab4c2882257395f6ccff75e
Messages are there, still hanging at "Waiting for DSMOS..."
New commit available for compilation. Only use this on USB (installer) media to test if it boots.
I can't find that file. It's not in /.IABootFiles when started in the installer gui.
Warnings/error in commit f1797b3933592a55e5a8ab42fa201893ee8a4bcc.
Lines 215 and 216 of PlatformExpert.cpp: conversion from 'int' to 'UINT8', possible loss of data
Lines 215 and 216 of PlatformExpert.cpp: conversion from 'int' to 'UINT8', possible loss of data