Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!uw-june!mckenzie
From: mckenzie@june.cs.washington.edu (Neil McKenzie)
Newsgroups: comp.unix.aux
Subject: Major bug in A/UX 1.1
Summary: A/UX 1.1 + X11 = bus errors!
Keywords: panic, double panic, kernel bus error
Message-ID: <8150@june.cs.washington.edu>
Date: 8 May 89 19:50:54 GMT
Reply-To: mckenzie@uw-june.UUCP (Neil McKenzie)
Distribution: na
Organization: U of Washington, Computer Science, Seattle
Lines: 44

I just installed the upgrade from A/UX 1.0.1 to A/UX 1.1 on my 
4 Mbyte Mac IIx ('030 version of the MacII).  There seems to be
a serious reliability problem with the new kernel running on my
computer.  I can make it crash by simply doing the following from
the shell:

	% rlogin localhost
	...
	% exit

The machine then dies and prints the error message:

	panic: sbflush 2

It is necessary to perform a cold restart at this point.
I've also seen similar problems when I run the new (color supported)
X11, running innocuous programs like "plaid" from a remote client.
The machine bombs and various messages come up:

	Double panic: mget

	Kernel bus error (then a register dump)
	Double panic: kernel memory management error


I tried playing with kconfig to increase different kernel parameters (as is
described in Chapter 2 of the "X Window System User's Guide for A/UX",
but this has no effect; the machine crashes the same way.

Fortunately I saved a copy of the 1.0.1 kernel and I am just using that
instead; it is highly robust.  Running the new X11 with the old kernel
is fine but just monochrome.  Both the new kernel and the new X11
server are necessary to make X11 work in color.


Questions:
Are there others (including people at Apple) who have seen these bugs?
Is there a fix in the works?

This problem is pretty serious -- serious enough to make this whole
upgrade unusable, since color X11 is the whole point of the upgrade,
for my purpose.

--Neil McKenzie (mckenzie@june.cs.washington.edu)