From lars@mcs.com  Fri May  5 22:44:35 1995
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Date: Sat, 6 May 1995 00:45:13 -0500
From: Lars Fredriksen <lars@mcs.com>
Reply-To: fredriks@mcs.com
To: FreeBSD-gnats-submit@freebsd.org
Subject: dd to from /dev/mem panics the machine.
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>Number:         383
>Category:       kern
>Synopsis:       dd to from /dev/mem panics the machine.
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          closed
>Quarter:        
>Keywords:       
>Date-Required:  
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri May  5 22:50:01 1995
>Closed-Date:    Thu Feb 8 08:58:24 PST 1996
>Last-Modified:  Tue Nov 27 18:41:54 PST 2001
>Originator:     & Fredriksen
>Release:        FreeBSD 2.1.0-Development i386
>Organization:
Flaaklypa Hackers
>Environment:
As far as I can tell the environment is not important here.

>Description:
The machine panics when you exectute the following command:

	dd if=/dev/mem of=/dev/null bs=10k count=1000

>How-To-Repeat:

	dd if=/dev/mem of=/dev/null bs=10k count=1000

>Fix:

	I don't have a panic dump at this point since I was in X when 
this happened. I will try to get one tomorrow, but I figured Jordan 
wanted to get this into his known-problems list.
>Release-Note:
>Audit-Trail:
State-Changed-From-To: open->closed 
State-Changed-By: wollman 
State-Changed-When: Thu Feb 8 08:58:24 PST 1996 
State-Changed-Why:  
It is an error to dd from random regions of /dev/mem.  All 
sorts of nasty things can happen. 
>Unformatted:


