Messages in this thread | | | Date | Wed, 14 Jul 2010 23:18:05 +0200 | From | Ingo Molnar <> | Subject | Re: [patch 1/2] x86_64 page fault NMI-safe |
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* Linus Torvalds <torvalds@linux-foundation.org> wrote:
> On Wed, Jul 14, 2010 at 1:17 PM, Mathieu Desnoyers > <mathieu.desnoyers@efficios.com> wrote: > > > > It only handles the case of a single NMI coming in. What happens in this > > scenario? > > [ two nested NMI's ] > > The _right_ thing happens. > > What do you think the hardware would have done itself? The NMI was blocked. > It wouldn't get replayed twice. If you have two NMI's happening while > another NMI is active, you will get a single NMI after the first NMI has > completed.
If it ever became an issue, we could even do what softirqs do and re-execute the NMI handler. At least for things like PMU NMIs we have to handle them once they have been (re-)issued, or we'd get a stuck PMU.
But in any case it should be a non-issue.
Ingo
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