Re: [PATCH 2.6.13] x86_64: Rename KDB_VECTOR to NMI_VECTOR

[Andi Kleen]

On Thursday 08 September 2005 18:39, Tom Rini wrote:
> The existing hook from KDB in the IPI code is really just a hook for the
> NMI vector.  We rename the vector thusly and then it's up to the
> debugger to handle things from do_default_nmi().

Jan Beulich pointed out some problems with this:

- First NMI vector is always 2 in the x86 architecture, so calling
another vector NMI_VECTOR is misleading.

- And when an NMI is forced in ICR the x86 architecture specifies
that the interrupt is delivered to vector 2.

Intel IA32  vol 3 8-23:

>>

100 (NMI) Delivers an NMI interrupt to the target processor
          or processors. The vector information is ignored.
<<

So how did this ever work?  I suspect you just got reentered
via the hooks in the NMI handler, but never through this vector.

I think I'll just remove this unless someone can explain how
it is supposed to work.

Thanks,
-Andi

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