From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750978AbcGMNxy (ORCPT ); Wed, 13 Jul 2016 09:53:54 -0400 Received: from out5-smtp.messagingengine.com ([66.111.4.29]:57928 "EHLO out5-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751515AbcGMNxp (ORCPT ); Wed, 13 Jul 2016 09:53:45 -0400 X-Sasl-enc: PYEpvooMFNwos36wj4bnse30Q5+NprBBtuOOo0R3hBrN 1468417981 Date: Wed, 13 Jul 2016 10:52:58 -0300 From: Henrique de Moraes Holschuh To: Joerg Roedel Cc: Meelis Roos , iommu@lists.linux-foundation.org, Linux Kernel list , David Woodhouse Subject: Re: IOMMU+DMAR causing NMIs-s (was: 4.7-rc6: NMI in intel_idle on HP Proliant G6) Message-ID: <20160713135258.GE20253@khazad-dum.debian.net> References: <5630546.0MIYeGNSYG@vostro.rjw.lan> <20160713081817.GJ12639@8bytes.org> <20160713090332.GK12639@8bytes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160713090332.GK12639@8bytes.org> X-GPG-Fingerprint1: 4096R/39CB4807 C467 A717 507B BAFE D3C1 6092 0BD9 E811 39CB 4807 User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 13 Jul 2016, Joerg Roedel wrote: > On Wed, Jul 13, 2016 at 11:31:02AM +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. > > > > BIOS P64 01/22/2015. There seems to be a newer 2015.08.16 BIOS out but > > the release notes only describe updated CPU microcode for security > > reasons. > > It is probably something HP is selling as a "feature" and not a BIOS > bug. Well, based on the date, it should be the microcode-level fix for this: https://www.blackhat.com/docs/us-15/materials/us-15-Domas-The-Memory-Sinkhole-Unleashing-An-x86-Design-Flaw-Allowing-Universal-Privilege-Escalation-wp.pdf -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh