[syslinux] Syslinux 5.00 - Doesn't boot my system / Not passing the kernel options to the kernel?

[Igor Sverkos]

Hi,

Shao Miller wrote:
> Does a kernel panic message appear after you click the OK button?

No.


> If you could get the kernel to spew out debugging messages to serial,
> perhaps you could capture a kernel panic message.  I don't know what VM
> software you are using, but I'm wondering if it is cutting off your
> kernel panic message because it detects the CPU halt before updating the
> display that you see.

I tried that (it is my first time debugging a booting kernel):

1) I configured the VMs like described in this documentation
<http://www.vmware.com/support/ws55/doc/ws_devices_serial_2vms.html>

2) I recompiled the kernel with KDBG and debug symbols.

3) I copied the uncompressed kernel to the VM, I am using for running gdb.

4) I added "kgdboc=ttyS0,115200 kgdbwait" to my kernel options in
extlinux.conf.

5) I started the VM I want to debug (was waiting as expected for a debugger)

6) I connected via gdb:

  root at ubuntu:/home/ubuntu# gdb /tmp/kernel/vmlinux
  GNU gdb (GDB) 7.2-ubuntu
  Copyright (C) 2010 Free Software Foundation, Inc.
  License GPLv3+: GNU GPL version 3 or later
<http://gnu.org/licenses/gpl.html>
  This is free software: you are free to change and redistribute it.
  There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
  and "show warranty" for details.
  This GDB was configured as "x86_64-linux-gnu".
  For bug reporting instructions, please see:
  <http://www.gnu.org/software/gdb/bugs/>...
  Reading symbols from /tmp/kernel/vmlinux...done.
  (gdb) set remotebaud 115200
  (gdb) target remote /dev/ttyS0
  Remote debugging using /dev/ttyS0
  kgdb_breakpoint () at kernel/debug/debug_core.c:1013
  1013	in kernel/debug/debug_core.c
  (gdb) cont
  Continuing.

  Program received signal SIGTRAP, Trace/breakpoint trap.
  kgdb_breakpoint () at kernel/debug/debug_core.c:1013
  1013	in kernel/debug/debug_core.c

As you can see, nothing was logged. Not sure if I am doing everything
right. As I mentioned, this was my first time...


-- 
Regards,
Igor