Subject: port-alpha/18565: kill -1 1 in single user mode ---> BLAM!
To: None <gnats-bugs@gnats.netbsd.org>
From: None <kpneal@pobox.com>
List: netbsd-bugs
Date: 10/06/2002 22:04:27
>Number:         18565
>Category:       port-alpha
>Synopsis:       kill -1 1 in single user mode leads to crash
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    port-alpha-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Oct 06 19:05:00 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Kevin P. Neal
>Release:        NetBSD 1.6
>Organization:
-- 
Kevin P. Neal                                http://www.pobox.com/~kpn/

"You know, I think I can hear the machine screaming from here...  \
'help me! hellpp meeee!'"  - Heather Flanagan, 14:52:23 Wed Jun 10 1998
>Environment:
System: NetBSD stone.neutralgood.org 1.6 NetBSD 1.6 (KPN-ALPHA-$Revision: 1.1 $) #0: Mon Sep 23 00:19:11 EDT 2002     kpn@neutralgood.org:/local/kernel/compile/ALPHA alpha
Architecture: alpha
Machine: alpha
>Description:

Note that I'm running a 1.6 kernel on a 1.5.2 userland.



In single user mode I did a kill -1 1. This caused init to crash. This,
in turn, caused the kernel to crash. 

My kernel config file is mostly the ALPHA file, with DEBUG and
DIAGNOSTIC turned on. 

There are multiple problems here:

1) init crashed
2) init's crash caused a kernel panic
3) savecore gave a garbled cause of crash

Here's the message from the kill -1 1:
CPU 0: fatal user trap:

CPU 0    trap entry = 0x2 (memory management fault)
CPU 0    a0         = 0x20
CPU 0    a1         = 0x1
CPU 0    a2         = 0x0
CPU 0    pc         = 0x120001aec
CPU 0    ra         = 0x120002614
CPU 0    pv         = 0x120033180
CPU 0    curproc    = 0xfffffc00002d6000
CPU 0        pid = 1, comm = init

ppp0: bad fcs 7c5
ppp0: bad fcs 3443
ppp0: bad fcs 9f55
ppp0: bad fcs 49c2
ppp0: bad fcs 237d
panic: init died (signal 0, exit 11)
syncing disks... 1 1 1 1 1 1 1 1 1 done
setclock: 50/10/1/23/36/43

dumping to dev 8,1 offset 98375
dump 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 succeeded


rebooting...

Here's what savecore had to say:
Checking for core dump...
savecore: reboot after panic: init died (signal %d, exit %d)
savecore: system went down at Tue Oct  1 19:36:43 2002

>How-To-Repeat:

Edit /etc/ttys, make changes. Save them. Get stupid, kill -1 1. Realize
after you've done it that you were in single user mode. Watch helplessly
as the machine panics despite the fact that pppd was working just
fine and the machine was routing packets just fine (the primary purpose
of the machine).

(Oh, I have no idea if the ppp0 messages were related or not.)

>Fix:

None provided.
>Release-Note:
>Audit-Trail:
>Unformatted: