Re: serial console and kernel 2.4

Eric Lamarque
2002-01-16T14:30:26Z

From: christophe barbé (christophe.barbe@lineo.fr)
Date: Mon Jul 30 2001 - 09:54:53 EST
> I recently upgraded a linux box to the kernel 2.4.4 .
> Since the upgrade I can see the boot output on the remote console
> but I can't use the keyboard

It seems that I experiment the same problem: I've some Compaq machine
that I control remotely with the serial console.

It always runs 2.4.x kernel and all runs fine.

I just replace the machine by a newer one and experiment the same problem
as you. It seems to me that Linux send CTRL-S on the serial line.

To check that this is the real problem, I use rlogin to access the machine
and send CTRL-Q to the Linux console: it does the trick.
( # echo -e "\021" > /dev/console )

I trace the problem to be the arch/i386/kernel/dmi_scan.c function:
DMI is a set of structures to get information about the machine.
It is the one that print "Board Version:.." at boot time.

I'll check at http://www.ibm.com/products/surepath/other/smbios.html to
know the type of such data. "Board Version" must be a string (I assume with
printable character).

My problem is that "Board Version" is printed as "Board Version: 0x14 0x13 *."
where 0x13 is CTRL-S.

Does the kernel contains a mechanism to avoid console printing of DMI information?
(If not, we could maybe add it in function dmi_scan.c:dmi_save_ident()).

Eric.