Sparc 20 with 2 60Mhz Sparc processors running Red Hat Linux
5.2.  I've put the packages Red Hat recommends for running a
2.2 kernel on Red Hat Linux 5.2.  I'm running the machine
headless, and when I boot the kernel (anything from 2.2.5 to
2.2.12) I get this on the console:

zs_open cua0, tty overwrite.
zs_open cua0, tty overwrite.
zs_open cua0, tty overwrite.
zs_open cua0, tty overwrite.
zs_open cua0, tty overwrite.
[ ... This will go on forever ... ]


The machine at this point seems to be running nicely if I
telnet in, but if I press a key on the serial console, the
kernel panics like so:


Unable to handle kernel NULL pointer
dereference<1>tsk->mm->context =
                  00000001 tsk->mm->pgd = f2e35000
                                \|/ ____ \|/
                                "@'/ ,. \`@"
                                /_| \__/ |_\
                                  \__U_/
ifup(125): Oops
PSR: 00900fc1 PC: f0141e24 NPC: f0141e28 Y: 10e69800
g0: f0041d64 g1: 00400fe3 g2: 00000021 g3: 00000021 g4:
e00e1040 g5:
00000000 g6
: ff00e000 g7: 00000000
o0: 00000001 o1: 00000003 o2: f2f18130 o3: e00e1050 o4:
00000000 o5:
00000002 sp
: ff00fc70 o7: f0141dd8
l0: 0000000d l1: f2f18000 l2: f018fde0 l3: f018fc00 l4:
00000001 l5:
f017f800 l6

I have tried replacing the inittab entry from referencing
cua0 to ttyS0, and also (out of sheer desparation) replacing
the call to getty with mgetty, all to no avail.

I should point out that I have no problems running headless
with a 2.0.35 kernel.