[syslinux] Creating Syslinux UEFI usb boot

[Gene Cumm]

On Thu, Apr 21, 2016 at 6:39 AM, Gene Cumm <gene.cumm at gmail.com> wrote:
> On Thu, Apr 21, 2016 at 3:29 AM, Atle Holm <atle at team-holm.net> wrote:
>> Under EFI/BOOT are the following files:
>> BOOTIA32.EFI  (from efi32/efi/syslinux.efi)
>> BOOTX64.EFI  (from efi64/efi/syslinux.efi)
>> ldlinux.sys  (copied from root of partition)
>> lua.c32
>> mboot.c32
>> menu.c32
>> syslinux.cfg
>> vesamenu.c32
>> KS.CFG (vmware specific)
>> BOOT.CFG (vmware specific)
>> autoselect.lua
>>
>> These files are also all under the root of the partition (except
>> BOOTIA32.EFI and BOOTX64.EFI) and work fine there if I use a normal bios
>> boot. When using UEFI boot, things don't work.
>
> I'd fully expect this.  Syslinux for EFI is incomplete.
>
>> If the .c32 files here are incorrect for UEFI boot, where do I get the
>> correct files?
>
> The same place as the other files.  You'll need at least
> efi64/com32/elflink/ldlinux/ldlinux.e64
>
>> I haven't been able to find a description/recipe on how to set up UEFI boot
>> with Syslinux. Why is there none, or where is it? That would probably be
>> easier.
>
> I had the impression from the first or second message you send that
> you already had a recipe.
>
> http://www.syslinux.org/wiki/index.php?title=Install#UEFI is a start.
>
> An additional config will be warranted.  In the root of the file
> system, a file named syslx64.cfg with
>
> #BEGIN syslx64.cfg
> PATH boot/syslinux/x64
> INCLUDE common.cfg
> #END syslx64.cfg
>
>
> For COM32 modules, you'll need at least (vesa)menu.c32, lua.c32,
> mboot.c32, and all of the libraries they depend on (though everything
> is easier) from within efi64/com32/ for the 64-bit placed in the
> boot/syslinux/x64 directory.
>
> Then rename your existing syslinux.cfg as common.cfg and create a new
> syslinux.cfg with
>
>
> #BEGIN syslinux.cfg
> PATH boot/syslinux/bios
> INCLUDE common.cfg
> #END syslinux.cfg
>
>
> and move the BIOS COM32 modules to that directory.
>
> I'm reasonably certain that the shuffling of your current syslinux.cfg
> and the current BIOS COM32 modules will be necessary as the EFI
> variants will likely try to load the BIOS COM32 module from the root
> instead of the directory in PATH and fail.

On Thu, Apr 21, 2016 at 10:46 AM, Atle Holm <atle at team-holm.net> wrote:

> OK, it now looks like this.
> /common.cfg (has contents of previously syslinux.cfg for menu and all)
> /syslinux.cfg
>         PATH BOOT/SYSLINUX/BIOS
>         INCLUDE common.cfg
> /syslx64.cfg
>          PATH BOOT/SYSLINUX/x64
>          INCLUDE common.cfg
> /BOOT.CFG (vmware specific)
> /KS.CFG (vmware specific)
> /EFI/BOOT/BOOTIA32.EFI
> /EFI/BOOT/BOOTX64.EFI
> /EFI/BOOT/ldlinux.e64
> /EFI/BOOT/ldlinux.elf
> /BOOT/SYSLINUX/BIOS/lua.c32  (241 KB)
> /BOOT/SYSLINUX/BIOS/mboot.c32 (79 KB)
> /BOOT/SYSLINUX/BIOS/menu.c32 (54 KB)
> /BOOT/SYSLINUX/BIOS/vesamenu.c32 (150 KB)
> /BOOT/SYSLINUX/x64/cmenu.c32 - from syslinux-6.03.zip\efi64\com32\lua\src
> /BOOT/SYSLINUX/x64/cpu.c32 - from syslinux-6.03.zip\efi64\com32\lua\src
> /BOOT/SYSLINUX/x64/dhcp.c32 - from syslinux-6.03.zip\efi64\com32\lua\src
> /BOOT/SYSLINUX/x64/dmi.c32 - from syslinux-6.03.zip\efi64\com32\lua\src
> /BOOT/SYSLINUX/x64/lfs.c32 - from syslinux-6.03.zip\efi64\com32\lua\src
> /BOOT/SYSLINUX/x64/liblua.c32 - from syslinux-6.03.zip\efi64\com32\lua\src
> /BOOT/SYSLINUX/x64/lua.c32 (9KB) - from
> syslinux-6.03.zip\efi64\com32\lua\src
> /BOOT/SYSLINUX/x64/mboot.c32 (13KB) - from
> syslinux-6.03.zip\efi64\com32\mboot
> /BOOT/SYSLINUX/x64/menu.c32 (32KB) - from syslinux-6.03.zip\efi64\com32\menu
> /BOOT/SYSLINUX/x64/pci.c32 - from syslinux-6.03.zip\efi64\com32\lua\src
> /BOOT/SYSLINUX/x64/syslinux.c32 - from syslinux-6.03.zip\efi64\com32\lua\src
> /BOOT/SYSLINUX/x64/vesa.c32 - from syslinux-6.03.zip\efi64\com32\lua\src
> /BOOT/SYSLINUX/x64/vesamenu.c32 (11 KB) - from
> syslinux-6.03.zip\efi64\com32\menu

Where are the library modules?  You can't load any of the x64 modules
without the libraries.  Search under efi64/com32/ for any lib*.c32
files.

> So when I do a BIOS boot, I now get:
>    Could not find kernel image: vesamenu.c32
> This used to work earlier.

Thinking about this now, you're probably going to have to skip the
BIOS/UEFI-ia32/UEFI-ia32-x64 hybrid in favor of a BIOS-only drive and
a UEFI-ia32/UEFI-ia32-x64 hybrid or skip using VMware's mboot.c32 and
boot.cfg (and instead stuff its data into your Syslinux config).  PATH
is a relatively newer directive not found in v3.86 or v4.05.

> When I do a UEFI boot, I now get:
>    Failed to load COM32 file: vesamenu.c32
> So that is progress.
>
> I tried placing the contents of /BOOT/SYSLINUX/x64 on the root of the disk
> and also inside /EFI/BOOT/ but that made no difference. I noticed that the
> c32 files that I found from syslinux-6.03.zip were alot smaller then the
> BIOS C32 files I have been using from syslinux 4.05 that came shipped with
> Ubuntu (see my notations above).
> I am guessing that the files in syslinux-6.03.zip need compiling of some
> sort to include all it should in the file?
> If so, how to do?
> Do I have to compile and install the whole syslinux-6.03 package to get the
> com32 modules?

static versus ELF linked binaries.  You don't need to compile anything.

-- 
-Gene