Syslinux - Jul 2014 - isohybrid: slint64-14.1.iso: unable to find mac efi image

> Hi,
> 
> > Unfortunately I get the error message:
> > isohybrid: slint64-14.1.iso: unable to find mac efi image
> 
> This is probably due to El Torito Platform id "Mac" in
> 
>   -eltorito-alt-boot -no-emul-boot -eltorito-platform Mac \
>     -eltorito-boot isolinux/macboot.img \
> 
> This caused in the image
>   http://slint.fr/misc/MacBoot/slint64-14.1.iso
> platform id 1 with the third image. (I would have expected 2
> from reading El Torito specs: 0=x86 , 1=PowerPC , 2=Mac. Shrug.)
> 
> Regardless whether this is the right number for the purpose of
> booting some Mac from CD/DVD, it is not what isohybrid.c
> expects.
> This program expects to find the UEFI image as second boot image
> and the Mac image as third boot image. Both with Platform Id 0xef.
> 
 
>From 
 cdrtools.sourceforge.net/private/man/cdrtools-3.01axx/mkisofs.8.html 


Look at the "-eltorito-platform id" option:

[quote]
 x86  This is the default platform id value  and  speci-
      fies   entries   for   the  PC  platform.   If  no
      -eltorito-platform option appears before the first
      -eltorito-boot  option,  the  default  boot  entry
      becomes an entry for the x86 PC platform.
 
 PPC  Boot entries for the Power PC platform.
 
 Mac  Boot entries for the Apple Mac platform.
 
 efi  Boot entries for EFI based PCs.
 
 #    A numeric value specifying any platform id.
[/quote]

I don't know about the specific "platform id" argument that the 
isohybrid tool expects for each case, but "efi", "Mac" and
"PPC" are
not the same for mkisofs.

If the isohybrid tool expects to use "efi" for "Mac" and/or
for
"PPC", then perhaps this might be part of the problem (if not now, at 
least at some point)?

Regards,
Ady.

Hi,

Ady wrote:
>  cdrtools.sourceforge.net/private/man/cdrtools-3.01axx/mkisofs.8.html 
>  Mac  Boot entries for the Apple Mac platform.
Interesting feature. But the El Torito specs of Phoenix and
IBM of 1994 state that "Mac" would be Platform Id 2.
  http://download.intel.com/support/motherboards/desktop/sb/specscdrom.pdf
  Page 9, Figure 2, Offset 1 of Validation Entry.

The ISO image slint64-14.1.iso exposed by Didier, shows in
the Validation Entry of the boot catalog: platform Id = 0.
The Section Header of the next section shows platform id = 0xef.
The next section header bears platform id = 1.

This is what isohybrid.c does dislike.
It's not incidential but explicitely written in its code.

Some background is told in
  http://mjg59.dreamwidth.org/11285.html
More adventures of Matthew Garrett get shown by googling
"mjg59 mac boot".

> If the isohybrid tool expects to use "efi" for "Mac"
and/or for
> "PPC", then perhaps this might be part of the problem (if not
now, at
> least at some point)?
Hard to say. It appears that Macs have variformous firmware,
and that what lets one machine boot lets the other machine fail.

I can tell you how to perform HFS+ blessing on byte level.
(Thanks to Vladimir Serbinenko who contributed HFS+ code to
 libisofs.)
But i cannot tell you when and why a blessing has to be issued
in order to achieve which beneficial effect.


Have a nice day :)

Thomas

> Hi,
> 
> Ady wrote:
> >  cdrtools.sourceforge.net/private/man/cdrtools-3.01axx/mkisofs.8.html 
> >  Mac  Boot entries for the Apple Mac platform.
> 
> Interesting feature. But the El Torito specs of Phoenix and
> IBM of 1994 state that "Mac" would be Platform Id 2.
>   http://download.intel.com/support/motherboards/desktop/sb/specscdrom.pdf
>   Page 9, Figure 2, Offset 1 of Validation Entry.
 
I don't understand why you say "*But* the El Torito...". I
don't see
a difference with what the mkisofs manual says.

Where I see some kind of source for potential confusion (at least for 
some users) is (quoting Thomas, but he is not the source of the 
potential confusion):
"This program expects to find the UEFI image as second boot image and 
the Mac image as third boot image. Both with Platform Id 0xef."

My understanding is that:
 0=x86 , 1=PowerPC , 2=Mac 
are all non-EFI systems, which leaves "0xef" for "every"
(U)EFI
system, whether such (U)EFI system is EFI 1.0, UEFI 2.x, a Mac-EFI 
system, or some mix/non-standard firmware.

So, users should be more specific (or clear) when they refer to a 
"Mac" system, as the firmware could be non-EFI, or (some variant of) 
(U)EFI.

Just as a remainder, "-eltorito-platform 0xEF" is equivalent to 
"-eltorito-platform efi" in mkisofs.

I would also suggest, at least **for test(s)**, to use the latest 
mkisofs (ATM, 3.01a24), and perhaps mixing it with Syslinux 
6.03-pre19 (or newer). Although... The scripts/receipts for using 
Syslinux 6.xx in Slackware would need changes, and I am certainly 
_not_ suggesting to actually update Slackware to use Syslinux 6.xx.

Regards,
Ady.