Messages in this thread | | | Subject | Re: [RFC][PATCH 3/3] x86: Add workaround to NMI iret woes | From | Peter Zijlstra <> | Date | Fri, 09 Dec 2011 10:22:01 +0100 |
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On Thu, 2011-12-08 at 21:43 -0500, Steven Rostedt wrote: > On Thu, 2011-12-08 at 14:36 -0500, Steven Rostedt wrote: > > > I'm not sure how to handle this case. We could do something similar in > > the break point code to handle the same thing. But this just seems > > really ugly. > > > > Anyone with any better ideas? > > On IRC, Peter Zijlstra mentioned changing the IDT in NMI. I'm not sure > if he was joking or not. But I decided to try it out. It seems to > work :)
Its was definitely tongue in cheek, also I did say this'll be a massive pain with paravirt since I doubt paravirt calls are NMI safe.
But yeah, it might all be slightly less painful than trying to teach the INT3 handler about this recursion.
This all started with wanting to do pagefaults from NMI context, those too will have this recursion, although for faults we'll end up in the double fault handler, which seems to allow a slightly saner way out.
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