Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84 SMI; site sun.uucp
Path: utzoo!linus!decvax!decwrl!sun!mojo
From: mojo@sun.uucp (Joseph Moran)
Newsgroups: net.unix-wizards,net.works
Subject: Re: Question on odd Sun behaviour
Message-ID: <2741@sun.uucp>
Date: Sun, 1-Sep-85 20:26:24 EDT
Article-I.D.: sun.2741
Posted: Sun Sep  1 20:26:24 1985
Date-Received: Mon, 2-Sep-85 09:21:45 EDT
References: <415@dcl-cs.UUCP>
Reply-To: mojo@sun.UUCP (Joseph Moran)
Organization: Sun Microsystems, Inc.
Lines: 27
Xref: linus net.unix-wizards:11838 net.works:869
Summary: 

In article <415@dcl-cs.UUCP> de@dcl-cs.UUCP (David England) writes:
>A couple of times now our Sun 120 has done a reboot after this, apparently
>harmless, command line (it didn't use to do this);
>% cat file | csvax lpr
>
>where csvax is a remote machine entry in /usr/host.
>
>The machine goes into KERNEL mode, does a traceback, gives a panic: Address
>error, then reboots. 
>
Well, as it turns out when the Sun kernel copies data out to the user
address space, it doesn't always check data alignment.  If a fault
occurs during the move, the kernel is supposed to detect that this
fault was not really a kernel fault, rather it is to be treated as a
user fault and the system call should return EFAULT or something like
that.  In the 1.x kernels, the address error fault code was not doing
this, and thus a bad pointer to certain system calls could cause an
address error panic.  The address error kernel bug is fixed in Sun
release 2.0.

Thus I'm hoping that you are running a 1.x kernel.  As to what system
call had a misaligned pointer in your example you got me.  I'd look at
a crash dump to look what's happening there.  If you get a 2.0 system
and you have the same system call parameters, the system call will
just fail instead of panic'ing the kernel.

	Joe Moran