Messages in this thread | | | Date | Wed, 14 Jul 2010 23:31:10 +0100 (BST) | From | "Maciej W. Rozycki" <> | Subject | Re: [patch 1/2] x86_64 page fault NMI-safe |
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On Wed, 14 Jul 2010, Linus Torvalds wrote:
> You just count differently. I don't count the first one (the "real" > NMI). That obviously happens. So I only count how many interrupts we > need to fake. That's my "one". That's the one that happens as a result > of the fault that we take on the iret in the emulated model.
Ah, I see -- so we are on the same page after all.
> (Yeah, yeah, you can call it a "one-bit counter", but I don't think > that's a counter. It's just a bit of information).
Hardware has something like a strapped-high D flip-flop (NMI goes to the clock input) with an extra reset input I presume -- this dates back to 8086 when the transistor count mattered with accuracy higher than 1e6. ;)
Maciej
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