Subject: port-alpha/6799: unexpected reboot with 'kernel stack not valid'
To: None <>
From: Matthew Jacob <>
List: netbsd-bugs
Date: 01/12/1999 15:58:09
>Number:         6799
>Category:       port-alpha
>Synopsis:       under light load Alpha 8200 reboots with 'kernel stack not valid'
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    port-alpha-maintainer (NetBSD/alpha Portmaster)
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Jan 12 16:35:01 1999
	NASA Ames Research Center
>Release:        source cvs updated as of Jan-12-1999, 1000PST.
System: NetBSD 1.3I NetBSD 1.3I (JULES) #0: Tue Jan 12 10:36:40 PST 1999 alpha


This has been around for a while but it's time to get serious about it.
Under moderately light load (building src), the kernel rebootes with:

halted CPU 8^M
halt code = 2^M
kernel stack not valid halt^M
PC = fffffc00004eadac^M

For this kernel, this is right at the front of uvm_fault
(fffffc00004eada0 T uvm_fault).

The config file (JULES) is actually just a copy of the ALPHA config file.

This particular machine as 2GB primary memory and ~2GB swap. I tried
to repeat the build with mfs on /tmp not mounted, but got the same


Run a build on the NetBSD /usr/src with the following script:

# A Script to do a nightly build of the NetBSD source tree (without
# trashing the running system)

set -a
# The location of your source tree.
# The location of the object files produced by the build.
# For the initial build, which doesn't include those crypto
# files which may not be exported from the US and Canada.
# These two aren't really necessary; they just make life
# easier if/when you rebuild later.
# The following variables must be set in the environment;
# /etc/mk.conf will not do!
# Where the installed files go.
# Where the .tgz files built for the release go.
# Set PATH and LD_LIBRARY_PATH to use the built items when possible.
# Strictly speaking this should all be done twice.
cd ${BSDSRCDIR} && make obj && make build