linux-kernel - Re: Bricked x86 CPU with software?

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Message-ID: <CAHp75VeK=_MnLCaAYoQOqcCN1TfKGXQKYAwHjEGnQfaGJkU2VQ@mail.gmail.com>
Date:   Thu, 4 Jan 2018 23:04:35 +0200
From:   Andy Shevchenko <andy.shevchenko@...il.com>
To:     Tim Mouraveiko <tim.ml@...opper.com>
Cc:     Pavel Machek <pavel@....cz>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: Bricked x86 CPU with software?

On Thu, Jan 4, 2018 at 11:00 PM, Tim Mouraveiko <tim.ml@...opper.com> 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 it愀 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