[syslinux] Cannot chainload a formerly working Linux system

[Ady Ady]

> Chainloading a Linux system with syslinux fails unexpectedly with the lines:
> 
> WARN: No MBR magic, treating disk as raw.
> ERR: Unable to find requested disk / partition combination.
> boot:
> 
> coming after the usual lines
>  SyslinuxBOOT ....                       (in UEFI menu)
>  linuxBLFS                               (in syslinux menu)
> 
 
 
 (snip)


> 
> File 'EFI/syslinux.cfg':
> DEFAULT menu.c32
> SAY Now booting the kernel from SYSLINUX...
> LABEL linuxBLFS
>    COM32 chain.c32
>    APPEND hdX 3
 
 
Why oh why!

 http://www.syslinux.org/wiki/index.php?title=Comboot/chain.c32#UEFI