From owner-freebsd-smp Sun Apr 30 18:43:54 2000 Delivered-To: freebsd-smp@freebsd.org Received: from mail.rdc2.bc.home.com (ha1.rdc2.bc.wave.home.com [24.2.10.68]) by hub.freebsd.org (Postfix) with ESMTP id 1E75737C09A for ; Sun, 30 Apr 2000 18:43:49 -0700 (PDT) (envelope-from dr@dursec.com) Received: from kyxbot.zorg ([24.113.134.64]) by mail.rdc2.bc.home.com (InterMail vM.4.01.02.17 201-229-119) with SMTP id <20000501014348.PXRO22959.mail.rdc2.bc.home.com@kyxbot.zorg>; Sun, 30 Apr 2000 18:43:48 -0700 From: Dragos Ruiu Organization: kyx.net To: Karl Pielorz , djb@ifa.au.dk Subject: Re: hlt instructions and temperature issues Date: Sun, 30 Apr 2000 18:36:46 -0700 X-Mailer: KMail [version 1.0.28] Content-Type: text/plain Cc: Steve Passe , smp@FreeBSD.ORG References: <200004300350.VAA13194@Ilsa.StevesCafe.com> <20000430152339.A453@relativity.student.utwente.nl> <390C4185.5C07088A@tdx.co.uk> In-Reply-To: <390C4185.5C07088A@tdx.co.uk> MIME-Version: 1.0 Message-Id: <00043018413807.18195@kyxbot.zorg> Content-Transfer-Encoding: 8bit Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Sun, 30 Apr 2000, Karl Pielorz wrote: > Taking it to an extreme, it would be like building a system that falls over > when it 'happens to be busy' one day, 'cause someone ran something > computationally intensive? - I know for a fact these systems do exist, but we > don't really want to be helping sweep the cause under the rug do we? > Tell that to IBM... one of the famous stories from classic computing history is the mainframe they built with the HCF opcode. Halt and Catch Fire. It turned out that for this model you could lock up into a tight one instruction loop and the CPU core would overheat and literally smoke. It's documented in the ancient back issues Mr. Neuman's old Risks usenet newsgroup in the early eighties. cheers, --dr -- dursec.com / kyx.net - we're from the future http://www.dursec.com learn kanga-foo from security experts: CanSecWest - May 10-12 Vancouver Speakers: Ron Gula/NSW, Ken Williams/E&Y, Marty Roesch/Hiverworld, Fyodor/insecure.org, RainForestPuppy/wiretrip.net, Theo de Raadt/OpenBSD Lance Spitzner/Sun, Fyodor Yarochkin/KALUG, Max Vision/whitehats.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message