Syslinux - Nov 2014 - Sysylinux-6.03 freezes at Loading kernel..., works smooth with 4.06 via SD-CARD

Hi,
I am trying to boot syslinux with an SD-Card on COMe-mBTi10 board, it works
perfect with syslinux 4-06(as BIOS supports booting from SD-CARD), but
hangs with syslinux-6.03 during 'Loading vmlinuz ... '.
I tried various ways in which I could debug but no hints, just one time I
got the error below the loading screen.

'Loading vmlinuz0 ... CHS: Error 8001 reading sector 34(0/3/3)
EDD: Error 8000 reading sector 50'

After this I never got the error again and it hangs. I have also tried
using sysdump.c32 and debug.c32, even they don't work.

In source code, in various files I traced the pattern 'Loading $ ...'
and
inserted strings to locate where exactly in the code my kernel hangs, then
I recomplied with
make bios installer
make install

After installation I tried installing syslinux using
syslinux -i /dev/sdb1   as well as
from the linux subdirectory ./syslinux.c --install /dev/sdb1
But no change.

The 'Loading kernel ...' pattern stays the same.
Also i could not find a documentation which shows how to compile from
source. Please help.

below is the Bios info and syslinux.cfg.
--
SMBIOS 2.7 present.
27 structures occupying 1122 bytes.
Table at 0x000E0840.

Handle 0x0000, DMI type 0, 24 bytes
BIOS Information
    Vendor: Kontron Europe GmbH
    Version: MVV1R111 X64
    Release Date: 10/14/2014
    Address: 0xE0000
    Runtime Size: 128 kB
    ROM Size: 4096 kB
    Characteristics:
        PCI is supported
        BIOS is upgradeable
        BIOS shadowing is allowed
        Boot from CD is supported
        Selectable boot is supported
        EDD is supported
        Print screen service is supported (int 5h)
        8042 keyboard services are supported (int 9h)
        Serial services are supported (int 14h)
        Printer services are supported (int 17h)
        CGA/mono video services are supported (int 10h)
        NEC PC-98
        ACPI is supported
        USB legacy is supported
        BIOS boot specification is supported
        Function key-initiated network boot is supported
        Targeted content distribution is supported
        UEFI is supported
    BIOS Revision: 2.9
--
Handle 0x0002, DMI type 2, 15 bytes
Base Board Information
    Manufacturer: Kontron Europe GmbH
    Product Name: COMe-mBTi10
    Version: C.0.4
--
syslinux.cfg
--
PROMPT 0
TIMEOUT 50

SERIAL 0

DEFAULT dbg
 LABEL dbg
   COM32 debug.c32
   APPEND bios_boot_linux free


#DEFAULT linux.c32 root=/dev/mmcblk0p2
#DEFAULT vmlinuz0 root=/dev/mmcblk0p2
DEFAULT mylabel
LABEL mylabel
COM32 sysdump.c32 ymodem xzy 0 9600
#KERNEL linux.c32
#APPEND vmlinuz0 initrd=initrd0.img root=/dev/mmcblk0p2 rootwait
rootfstype=ext3 console=tty0 console=ttyS0,9600

LINUX vmlinuz0
#KERNEL vmlinuz0
APPEND root=/dev/mmcblk0p2 bios_boot_linux free
INITRD initrd0.img

#APPEND root=/dev/mmcblk0p2 rootwait rootfstype=ext3 console=tty0
console=ttyS0,9600
#APPEND initrd=initrd0.img root=/dev/mmcblk0p2 rootwait rootfstype=ext3
console=tty0 console=ttyS0,9600
--

I have tried every possible combination but no success at all. When i try
to use linux.c32 comboot module, it does not even say Loading vmlinuz0 ...
it hangs even before that.

The same kernel and initrd works perfectly with Syslinux-4.06 where it
boots from SD-card without any single error.
Please help or suggest.
best regards.
Micheal

> Hi,
> I am trying to boot syslinux with an SD-Card on COMe-mBTi10 board, it works
> perfect with syslinux 4-06(as BIOS supports booting from SD-CARD), but
> hangs with syslinux-6.03 during 'Loading vmlinuz ... '.
> I tried various ways in which I could debug but no hints, just one time I
> got the error below the loading screen.
> 
> 'Loading vmlinuz0 ... CHS: Error 8001 reading sector 34(0/3/3)
> EDD: Error 8000 reading sector 50'
 
Have you tried to install Syslinux 4.06 on the SD-Card again? Is it 
still working?
 
> 
> After this I never got the error again and it hangs. I have also tried
> using sysdump.c32 and debug.c32, even they don't work.
 
You need to use the c32 files from the same version of the bootloader.
 
> 
> In source code, in various files I traced the pattern 'Loading $
...' and
> inserted strings to locate where exactly in the code my kernel hangs, then
> I recomplied with
> make bios installer
> make install
> 
> After installation I tried installing syslinux using
> syslinux -i /dev/sdb1   as well as
> from the linux subdirectory ./syslinux.c --install /dev/sdb1
> But no change.
 
Surely you know that "./syslinux.c" is not the installer.

In 6.03, the installer you are referring to is located in:

 syslinux-6.03/bios/linux/ 

In any case, the syslinux command requires for you to first *UNmount* 
the filesystem on which you are installing SYSLINUX, before you execute 
the installer. By leaving the filesystem mounted while executing the 
syslinux installer you might corrupt such filesystem.

And, again, you need to copy the corresponding c32 files from the same 
version of the installer. For Syslinux 6.03, these are under the 
"/bios/" subdirectory.

Using c32 files from different versions than the bootloader or from a 
different firmware/architecture (e.g. efi64) will most probably fail.
> 
> The 'Loading kernel ...' pattern stays the same.
> Also i could not find a documentation which shows how to compile from
> source. Please help.
> 
> below is the Bios info and syslinux.cfg.
 
 (snip)
 
> 
> I have tried every possible combination but no success at all. When i try
> to use linux.c32 comboot module, it does not even say Loading vmlinuz0 ...
> it hangs even before that.
> 
> The same kernel and initrd works perfectly with Syslinux-4.06 where it
> boots from SD-card without any single error.
> Please help or suggest.
> best regards.
> Micheal
> _______________________________________________
> Syslinux mailing list
> Submissions to Syslinux at zytor.com
> Unsubscribe or set options at:
> http://www.zytor.com/mailman/listinfo/syslinux
> 
The content of syslinux.cfg as you posted it is inadequate, probably 
because you are blindly testing several possibilities (for example, you 
have more than one DEFAULT directive).

I would suggest temporarily changing the name of any "syslinux.cfg"
and
of any "extlinux.conf" files you might have (in _any and every_ 
location, including in "/[boot/]syslinux/" and
"/[boot/]extlinux/".

When SYSLINUX fails to find the configuration file (using any of its 
naming alternatives in any of its alternative locations), it should 
show you the boot prompt and a message (about not finding the 
configuration file). In this context, this means SYSLINUX was 
successful to boot your SD-Card.

Since you are comparing with Syslinux 4.06, you should also double 
check that you are actually trying to boot in CSM (aka. BIOS) mode, not 
in UEFI.

Regards,
Ady.

Hi
I have tried to install syslinux 4.06 on the SD card again, it works like a
charm.

I am being very carefull with c32 files from the same version bootloader.
No success.

I am also unmounting /dev/sdb1 before installing syslinux, as mentioned in
the given documentations.
In the pasted syslinux.cfg content--- I have also tried using only one
DEFAULT directive. No success.
syslinux boots successfully into SD-CARD thats for sure, as I do get the
boot prompt and I can even choose to load initrd0.img first, which shows
loading successful. But when it comes to loading the kernel, the system
hangs.

UEFI mode is disabled in my BIOS.
Also I tested today the same installation procedure on a USB. Now here is
the interesting part, in booting from a USB with the same settings and
configuration. The kernel loads successfully but a new error shows up
resulting in a system hang.
 ' Loading vmlinuz0 ... ok
Loading initrd0.img... ok
Probing EDD (edd=off to disable)... '
The problem starts when syslinux tries to load kernel file into the memory,
for some reason it tries to read the wrong addresses, or maybee it
calculates the addresses wrongly. I have tried several paritions sizes
<128M  >128M ... no success.
On your changelog, i see that you converted lots of assembly code into C,
somewhere there is the bug, which is not allowing for a successful load of
the kernel for the SD-Card case, and for the USB-case kernel is loaded but
again Probing EDD gets to compute the addresses wrongly.
there is a bug in the Syslinux-6.03 code, otherwise syslinux-4.06 should
have also shown similar issues, but it works like a charm.

Could you please point me to a documentation which allows for complete
compilation from scratch???

/micheal