Re: [PATCH], issue EOI to APIC prior to calling crash_kexec in die_nmi path

From: Neil Horman
Date: Wed Feb 06 2008 - 16:05:37 EST


On Wed, Feb 06, 2008 at 12:21:30PM -0800, H. Peter Anvin wrote:
> Neil Horman wrote:
> >Can an APIC accept an NMI while already handling an NMI? I didn't think
> >they
> >would interrupt one another, but rather, pend until such time as the
> >previous
> >NMI was cleared
>
> The CPU certainly won't (there is a hidden flag that's cleared on IRET
> which disables NMI; it's possible to re-enable NMI by executing a dummy
> IRET inside the NMI handler.)
>
> -hpa

So that would be another solution I would expect. Would you rather I
investigate that, or is the proposed solution more reasonable?

Neil


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