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From: ballou@wheatena (Kenneth R. Ballou)
Newsgroups: comp.sys.ibm.pc
Subject: Re: 386 rumors, questions, and comments
Message-ID: <1197@cartan.Berkeley.EDU>
Date: Wed, 26-Aug-87 22:55:31 EDT
Article-I.D.: cartan.1197
Posted: Wed Aug 26 22:55:31 1987
Date-Received: Sat, 12-Sep-87 10:05:26 EDT
References: <1014@vi.ri.cmu.edu>
Sender: nobody@cartan.Berkeley.EDU
Reply-To: ballou@wheatena.UUCP (Kenneth R. Ballou)
Organization: /usr/local/lib/organization
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Keywords: protection sun machine

In article <1014@vi.ri.cmu.edu> jfb@vi.ri.cmu.edu (John Brennen) writes:
>First, someone posted saying that a user-level task can bring down a 386
>machine.  How?

	I was surprised while reading the 80386 Programmer's Reference
Manual to see that in Virtual 8086 mode, the instructions IN, INS, OUT,
and OUTS are *not* IOPL (I/O Privilege Level) sensitive.  So, for example,
a user task could reset the CPU in the same way as one resets the 80286 in
the AT by sending an appropriate command to the 8042.