[syslinux] pxelinux 5.x, 6.x memtest problem

[Ady]

> Hello,
> 
> FYI. This problem looks similar to the problem I reported in Februari
> http://www.syslinux.org/archives/2013-February/019517.html
> 
> Kind regards,
> Wim.
> 
> On 06/28/2013 10:02 AM, Matt Fleming wrote:
> > On Fri, 28 Jun, at 08:13:03AM, Németh Péter wrote:
> >> Hi guys!
> >> I tried to boot memtest86+ v4.2 (renamed memtest.bin to memtest), and
> >> i have issues to boot it with pxelinux 5.x and greater.Pxelinux 4.06
> >> works fine both memtest 4.1 and 4.2.
> >> With version 6.00 no error message caught, only writes out dots. Any
> >> keypress does a reboot.With version 5.01 the error message is the
> >> follow:Loading images/memtest/memtest86... okBooting kernel failed:
> >> Bad file number
> >> The pxelinux.cfg/default file contents:DEFAULT memtest2
> >> LABEL memtest    KERNEL images/memtest/memtest.original    APPEND console=ttyS0,9600n8
> >> LABEL memtest2    KERNEL images/memtest/memtest86    APPEND console=ttyS0,9600n8
> >> PROMPT 1TIMEOUT 100
> >> Any ide how to solve this?
> >
> > This is the infamous PXE-stack-smasher-bug. It's a regression in the
> > 5.xx series (which means it's also in the 6.xx series). This has been
> > one of those difficult to reproduce bugs, because it's very much
> > dependent on the BIOS memory map.
> >
> > Is anyone that is hitting this issue willing/able to build PXELINUX from
> > a git branch to help with debugging this?
> >
> 
> -- 
> Wim Janssen                    Email: WPJ.Janssen at science.ru.nl
> Radboud University Nijmegen
> Faculty of Science,            room:  HG03.055
> C&CZ                           tel:   +31243652744
> _______________________________________________

@Wim and @All,
 FWIW, in 2013-February there still were other additional issues with 
some kernels, including memory testers, so having a problem to boot 
memtest(86|86+|other) might or might not be related to the 
"PXE-stack-smasher" bug.

For example, in v.4.06, the cfg entry could be:
 LINUX memtest

and it would work OK, but if the entry was:
 COM32 linux.c32
 APPEND memtest

it could / would fail, even using SYSLINUX (or PXELINUX). This 
behavior with linux.c32 seemed to indicate that there were already 
potential problems ahead in Syslinux 5.xx with certain kernels.

Also, as a remainder, memtest is for BIOS only (AFAIK, at least 
current versions).

So, if someone was having problems with memtest before, I would 
suggest trying again with the latest Syslinux build(s), booting with 
SYSLINUX and with PXELINUX. Comparing the results might help clarify 
whether the problem is actually related to the "PXE-stack-smasher" 
bug, or to something else (which might have been already solved in 
the last few months / days / hours).

Best Regards,
Ady.