Re: [Etherboot-developers] rtl_disable and random kernel crash.

[Ken Y. <ke...@nl...>]

>I think the source of the problems with local booting and 4.7.23 is the
>PCI_PNP_HEADER patch.  If you look closely at the code below the "over:"
>label at line 138, the "#ifdef - #endif" labels for PCI_PNP_HEADER and
>NOINT19H are mismatched (i.e., "#endif /* PCI_PNP_HEADER */" appears
>_between_ the "#ifdef NOINT19H" conditional and its associated "#endif").

You're right. The wrong comments are attached to the #endifs, but
nonetheless the code is also not what was intended. That's what happens
when your brain gets mushed by trying to save lines and looking at
inverse logic.

>I think the original intention was:
>1. If compiled for PCI_PNP, the system BIOS will invoke the "blockmove"
>entrypoint defined in the "$PnP" structure, so there is no need to do _any_
>initialization via the option ROM entry at offset 3 in the code (which jumps
>to label "over:").  I'm not sure of the significance of returning 0x20 in ax
>at this point, so I left it there.

The initialisation has to return 0x20 in %ax to indicate a bootable
device.

>2. If the ROM is not PCI_PNP, you have two options: trap INT19, or not.
>2a. INT19 trapped: patch the INT19 vector, and return to the system BIOS,
>which will invoke INT19 when initialization is complete and it is ready to
>boot.
>2b. No INT19 trap: assume no further initialization by the system BIOS is
>necessary - simply grab control and don't give it back.
>
>I submit the code below is more correct than that currently in 4.7.23.
>This may (or may not) resolve some of the issues with inability to "local"
>boot after the etherboot ROM is invoked.

Thanks, you found the problem. I'll fix this now.