[syslinux] Dynamic debugging how to WAS: Syslinux-6.02-pre2 - booting 32-bit kernels from efi64

[Gene Cumm]

On Sun, Jul 14, 2013 at 3:50 PM, Gene Cumm <gene.cumm at gmail.com> wrote:
> On Fri, Jul 12, 2013 at 9:49 AM, Matt Fleming <matt at console-pimps.org> wrote:
>> On Thu, 11 Jul, at 10:44:27PM, Geert Stappers wrote:
>>> Op 2013-07-11 om 16:17 schreef Matt Fleming:
>>> > On Wed, 10 Jul, at 03:44:57PM, Andreas Heinlein wrote:
>>> > >
>>> > > Any further info I can give you to debug this? Are there any
>>> > > specific requirements for the kernel?
>>> >
>>> > You could try running,
>>> >
>>> > debug.c32 -e efi_boot_linux handover_boot
>>> >
>>> > before executing your kernel.
>>>
>>>
>>> Euh how? Where?
>>>
>>> In a syslinux config file?
>>> At the `boot:` prompt?
>>>
>>> Please provide an example.
>>
>> It needs a lot of work but an example is here,
>>
>> http://www.syslinux.org/wiki/index.php/Development/Debugging#Syslinux_Dynamic_Debugger
>
> Is the dynamic debugger information better there or
> http://www.syslinux.org/wiki/index.php/Debugging a newer page I made
> to help end-users, especially those who don't have experience
> compiling Syslinux and/or don't have a reliable build machine for
> Syslinux?
>
> Is there a way to modify a binary (especially pxelinux.0) such that
> certain key debug messages are active?  I've got my UNDI debug (just
> drops up to 3 lines via dprintf() per packet sent or received) and was
> wondering how to make a build that could coexist (without a rebuild)

After seeing how chatty free(), malloc() and  __schedule() (which I
silenced with a shift to dprintf2() and a temp #ifdef on DEBUG_MALLOC)
are on a serial console when making a static debug build, I wondered
if the dynamic debug messages are strictly sent to the current console
or serial console and if this could be configurable.  It appears it's
strictly the current console (based on SERIAL/CONSOLE) and not
configurable.

--
-Gene