Re: IOMMU+DMAR causing NMIs-s (was: 4.7-rc6: NMI in intel_idle on HP Proliant G6)

From: Joerg Roedel
Date: Wed Jul 13 2016 - 04:18:31 EST


On Wed, Jul 13, 2016 at 10:17:59AM +0300, Meelis Roos wrote:
> Bisecting kernel configs shows that it's DMAR+IOMMU. When it is
> activated, there is high probability of NMI-s in random places.

Hmm, strange. But nothing could really surprise when you have an HP
BIOS.

Can you probably use the faulty config and bisect this down to a
specific commit? In v4.7-rc1 some changes to the iova-allocation code
got merged, but I have no idea how those could cause NMIs.


Thanks,

Joerg