Re: [PATCH] x86 (64): make calibrate_APIC_clock() smp-safe

[Cyrill Gorcunov <gorcunov@gmail.com>]

[Martin Wilck - Thu, Jul 24, 2008 at 01:58:37PM +0200]
> Cyrill Gorcunov wrote:
>
>> Hi, but what if SMI flood happens? We could stuck here forever, don't we?
>>
>>                 - Cyrill -
>
>
> Yes, if the SMI flood never ends. But you wouldn't want to work on such  
> a system anyway (with the current kernel code, your APIC timer would  
> most probably be miscalibrated, which can have the weirdest effects).
>
> Anyway, we can add a maximum iteration count to the patch so that there  
> is no risk of getting stuck.
>
> Martin
>
> -- 
> Martin Wilck
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yes, it will issue some effects but it's better then stuck there.
More over in 'case of SMI flood with current patch you don't get
error message printed i think so you better add max iteration
counter so user will see on console (or whatever) that he is got
problems.
		- Cyrill -