serial console -- busted under 2.4.6 and thereabouts?

[Chris Wedgwood]

I'm trying to get serial console working under 2.4.6-pre3; I see
previous messages about the CREAD 'bug' but I'm pretty sure I am
seeing something else.

Basically, the serial port works with lilo, and with getty once the
system is booted, but I don't get any kernel messages on the console
and serial-SysRq doesn't work.

If I go back to a 2.4.3 (or maybe 2.4.2-pre? kernel) I build some
months ago (hence why I am unsure of the exact version) it works as
expected.

Diffing I see no kernel/printk.c changes, and the only
drivers/char/serial.c changes I see don't explain my problem.

At first, I thouht it might be divider problem or failing to set the
bit-rate, as I use 38400, but if I change to 9600 when I
_should_ get kernel messages (after lilo says booting kernel), I can
actually see them... but as to why to why this is the case I'm lost.

I have tried drivers/char/serial.c from 2.4.3 in 2.4.6-pre3 and that
doesn't work either.

Suggestion anyone?

    --cw