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Subject: Re: [RFC PATCH v2 6/6] x86/entry/pti: don't switch PGD on when
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To: Andy Lutomirski <luto@kernel.org>
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On 01/11/2018 09:02 AM, Andy Lutomirski wrote:
>> But, the stack gets really fun because of NMIs.
>>
>> I'm sure Andy Lutomirski has some ideas too.
> I was thinking that maybe we should add a new field or two to pt_regs.
> They could store CR2 and maybe CR3 as well.  I'd also like to expose
> the error code of exceptions in stack traces.  We should get this
> integrated right into the unwinder.

The trampoline and (normal) interrupt stacks should be pretty doable.

It's the NMI mess that I'm worried about.  I tried to change the stack
layout in there once and ran away screaming.