[syslinux] mboot.c32, NUMA and tgz

[Hansen, Timbonicus]

Sounds reasonable -- what do you mean by replacing the core? What elements are required besides the mboot.c32? I must admit little knowledge of syslinux, but I got the impression that VMware is not using much of the package. Here are the files present that successfully get an install going:

boot.cat
cim.vgz
cimstg.tgz
ienviron.tgz
image.tgz
install.tgz
isolinux.bin
isolinux.cfg
mboot.c32
menu.c32
readme.txt
sys.vgz
vmkboot.gz
vmkernel.gz

What parts are from syslinux that I would need to replace in order to upgrade the mboot.c32? Or is impossible to tell without decompressing and examining the files?

Thanks,

Tim Hansen
timbonicus.hansen at hp.com

-----Original Message-----
From: H. Peter Anvin [mailto:hpa at zytor.com] 
Sent: Tuesday, July 21, 2009 11:02 AM
To: For discussion of Syslinux and tftp-hpa
Cc: Hansen, Timbonicus
Subject: Re: [syslinux] mboot.c32, NUMA and tgz

Hansen, Timbonicus wrote:
> Hi all,
> 
> I'm attempting to PXE boot ESXi, which uses the syslinux mboot.c32 module. The mboot.c32 included with ESXi seems to be an older version that runs into an "out of memory loading.." problem halfway through, even though the box has 8GB memory. This may be related to NUMA, since it works fine on an older box but not the newer blade. I saw that some non-contiguous memory issues have been fixed in newer versions of syslinux and tried replacing the mboot.c32 with the 3.82 release, but now it seems to hang forever when loading a .tgz file.
> 
> Does mboot.c32 support tgz out of the box, or is this something VMware added in for ESXi? Do I need to recompile mboot or otherwise do something special to enable it? Is there a workaround for the previous memory issue?
> 

You can't just replace a .c32 file without replacing the core.

As far as .tgz is concerned, it would depend on what exactly VMware is
expecting to be done with the .tgz file.  Since the Multiboot spec
explicitly defers to the Grub implementation (not even saying which
version...), mboot.c32 mimics Grub behavior and will decompress a
compressed file, but it doesn't do anything special with the resulting
tarball.

As far as if VMware modified anything in ESXi, you'd have to ask VMware.
 Note that the old mboot.c32 was GPL, and so they should have to release
sources; the new mboot.c32 is MIT.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.