Re: [RFC/SERIOUS] grilling troubled CPUs for fun and profit?

[Pavel Machek]

Hi!

> while looking for loop places to apply cpu_relax() to, I found the
> following gems:
> 
> arch/i386/kernel/crash.c/crash_nmi_callback():
> 
>         /* Assume hlt works */
>         halt();
>         for(;;);
> 
>         return 1;
> }
> 
> arch/i386/kernel/doublefault.c/doublefault_fn():
> 
>         for (;;) /* nothing */;
> }
> 
> Let's assume that we have a less than moderate fan failure that causes
> the CPU to heat up beyond the critical limit...
> That might result in - you guessed it - crashes or doublefaults.
> In which case we enter the corresponding handler and do... what?
> Exactly, we accelerate the CPUs happy march into bit heaven by letting it

...
> Am I completely missing something here?

Yes. You are missing that modern hw already protects itself. See my  blog on planet.kernel.org.

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