[syslinux] Plop Boot Manager quit working with 5.10

[Ady]

> On 06/28/2013 05:32 PM, Patrick Verner wrote:
> > I have updated syslinux in Parted Magic's test version to the 5.10 release.
> > With 4.06 I booted plop like this:
> > 
> > LINUX /boot/plpbt/plpbt.bin
> > 
> > Now it says /boot/plpbt/plpbt.bin... ok
> > Booting kernel failed: Invalid argument
> > 
> > Other "extras" like IPXE, HDT, memtest86+, chntpw, Super Grub Disk, etc...
> > all work with 5.10. Revert to 4.06 and plop works again.
> > 
> > Is this a problem with syslinux or plop?
> > 
> 
> I suspect this is the "ancient kernel" problem again.  Do you have a
> point to the specific plpbt.bin you are using?
> 
> 	-hpa
> 
 
If with "ancient kernel" you are referring to the memtest(86|86+) 
issue, I don't see the same *exact* problem / behavior.

FWIW, let me give you some examples, with Syslinux 6.01-pre5 BIOS, 
and/or with 5.11-pre3, testing with the same VBox 4.2.14 VM. I have 
also deleted the ".bin" filename extension from the kernels.

Note: In this context, when I mention "plop" here, I am referring to 
"PLoP boot manager" only, and not to other products which include the 
word "PLoP" in it from the same developer.

_ I am able to boot ISOLINUX -> memtest, but not ISOLINUX -> plop.

_ memtest seems to fail mostly from PXELINUX, or when using 
linux.c32.

_ Some versions of memtest seem to start booting (from ISOLINUX, for 
example) but then hang within memtest itself (possible memtest bug?). 
OTOH, when trying to boot plop, is Syslinux the one refusing to boot 
the plop kernel at all, giving some error message. BTW, to be sure 
you can see the exact error message, you might need to use CLI; using 
menu.c32 might immediately erase the error message from the screen, 
going back to display the Syslinux menu. Note that the error message 
is not the same, depending on whether linux.c32 was used or not.

_ Using MEMDISK -> plpbt.img (FAT12 bootable floppy image with plop 
as boot loader in it), plop can be booted. This is a particular case, 
since plop itself is a boot loader; this is not applicable to 
memtest.

So the problem with plop seems to be trying to boot the kernel 
directly, from whichever variant of Syslinux 5+, while memtest can 
still be booted directly with at least some variants of Syslinux 5+. 
Using MEMDISK, plop can be booted.

Of course, please keep in mind that these tests were performed in one 
VM only, and different real hardware might behave differently.

Regards,
Ady.