Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753304AbeADVEh (ORCPT + 1 other); Thu, 4 Jan 2018 16:04:37 -0500 Received: from mail-qt0-f172.google.com ([209.85.216.172]:36560 "EHLO mail-qt0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753199AbeADVEg (ORCPT ); Thu, 4 Jan 2018 16:04:36 -0500 X-Google-Smtp-Source: ACJfBoseLNN4S7aAFJzdzx6pgcGniceot2BllVAyHjsyHsDWimANpTMlyGOYD+ObLu987SUsF2vLe3OkVLyv00nKoZ0= MIME-Version: 1.0 In-Reply-To: <5A4E9603.20778.21CD7C4@tim.ml.ipcopper.com> References: <5A4D7986.2138.FDC590CF@tim.ml.ipcopper.com> <20180104200637.GC10427@amd> <5A4E9603.20778.21CD7C4@tim.ml.ipcopper.com> From: Andy Shevchenko Date: Thu, 4 Jan 2018 23:04:35 +0200 Message-ID: Subject: Re: Bricked x86 CPU with software? To: Tim Mouraveiko Cc: Pavel Machek , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On Thu, Jan 4, 2018 at 11:00 PM, Tim Mouraveiko wrote: > Pavel, > > As I mentioned before, I repeatedly and fully power-cycled the motherboard and reset BIOS > and etc. It made no difference. I can see that the processor was not drawing any power. The > software code behaved in a similar fashion on other processors, until I fixed it so that it would > not kill any more processors. > > In case you are curious there was no overheating, no 100% utilization, no tampering with > hardware (GPIO pins or anything of that sort), no overclocking and etc. No hardware issues > or changes at all. Please, do not top post. Just to be sure, have you checked same CPU on different motherboard? It might be that voltage regulators on it just died. >> > In all my years of extensive experience writing drivers and kernels, I never came across a situation >> > where you could brick an x86 CPU. Not until recently, when I was working on debugging a piece of >> > code and I bricked an Intel CPU. I am not talking about an experimental motherboard or anything >> > exotic or an electrical issue where the CPU got fried, but before the software code execution the CPU >> > was fine and then itæ„€ dead. There were signs that something was not right, that the code was causing >> > unusual behavior, which is what I was debugging. >> > >> > Has anyone else ever experienced a bricked CPU after executing software code? I just wanted to get >> > input from the community to see if anyone had had any experience like that, since it seems rather >> > unusual to me. >> >> Never seen that before. Can you try to brick another one? :-). >> >> You may want to remove AC power and battery, wait for half an hour, >> then attempt to boot it... >> >> Pavel >> -- >> (english) http://www.livejournal.com/~pavelmachek >> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html >> > > -- With Best Regards, Andy Shevchenko