Re: [PATCH] x86-64: espfix for 64-bit mode *PROTOTYPE*

[H. Peter Anvin]

On 04/22/2014 11:17 AM, Brian Gerst wrote:
>>
>> That is the entry condition that we have to deal with.  The fact that
>> the switch to the IST is unconditional is what makes ISTs hard to deal with.
> 
> Right, that is why you switch away from the IST as soon as possible,
> copying the data that is already pushed there to another stack so it
> won't be overwritten by a recursive fault.
> 

That simply will not work if you can take a #GP due to the "safe" MSR
functions from NMI and #MC context, which would be my main concern.

	-hpa

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