From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752795AbcBVCDP (ORCPT ); Sun, 21 Feb 2016 21:03:15 -0500 Received: from m199-177.yeah.net ([123.58.177.199]:49212 "EHLO m199-177.yeah.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752594AbcBVCDO (ORCPT ); Sun, 21 Feb 2016 21:03:14 -0500 X-Greylist: delayed 540 seconds by postgrey-1.27 at vger.kernel.org; Sun, 21 Feb 2016 21:03:13 EST Subject: Re: Warning from AMD IOMMU performance counters To: Laura Abbott , Joerg Roedel , Suravee.Suthikulpanit@amd.com References: <56C798B8.6080009@redhat.com> Cc: iommu@lists.linux-foundation.org, Linux Kernel Mailing List From: Wan Zongshun Message-ID: <56CA69C7.3050508@iommu.org> Date: Mon, 22 Feb 2016 09:52:07 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.2; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <56C798B8.6080009@redhat.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-HM-Spam-Status: e1koWUFPN1dZCBgUCR5ZQVZLVUpDQkJCQkNKQ0NLSkNMQkNDV1kJDhceCF lBWSgrPSQrOigoJDI1JDM#Oj8#KUFLVUtANiMkIj4oJDI1JDM#Oj8#KUFLVUtAKy8pJCI#KCQyNS QzPjo*PilBS1VLQDg0LjUvKSIkODVBS1VLQCk#PDI0NSQ6KDI6QUtVS0ArKTQtMjU4PiQoMzo1PD M6MkFLVUtAPyI1OjYyOCQyKyQ1NCQyNSQzPjo*PilBS1VLQDYuNy8yJCk4Ky8kPzI9PT4pPjUvJD I1JDM#Oj8#KUFJVUtAMiskSiQ2MjUuLz4kODUvJEskSktBS1VLQDIrJEhLJDYyNS4vPiQ4NS8kSy ROS0FLVUtAMiskLzQ*OiIkODUvJEskSktLQUtVS0AyKyROJDYyNS4vPiQ4NS8kSyRKS0FLVUtAMi skSiQzNC4pJDg1LyRLJEpLS0FLVUtAKC45MT44LyROJDYyNS4vPiQ4NS8kSyRKS0FLVUtAKC45MT 44LyQvND86IiQ4NS8kSyRKS0tBS1VLQCguOTE#OC8kSiQzNC4pJDg1LyRLJEpLS0FLVUtAPTUkLi k3JDMvLysoJDM3MSRLQ0tKS0NBS1VLQD01JDY6IiRPSkIkMzcxJEokS0NLSEtPQUtVSEhAPSskKT 4kPSwkMzcxJEtDS0hLTUFWTFVOQD01JCguOSQ#NSw0KT8oJDM3MSRKS0tJS0pBS1VJQ0AoLjkkPk FKVU5OQD01JDkyL0wkMzcxJEtMSklLSUFIVUpOWQY+ X-HM-Sender-Digest: e1kSHx4VD1lBWUc6MDo6Qzo*GToxDQsSDwkJCywIEhZPCT9VSlVKT05N SktNS09DTExOVTMWGhIXVQ0MOxIUFhYOVRQJHEVZV1kMHhlZQR0aFwgeV1kIAVlBSElMTjdXWRIL WUFZSUpLVUpIVUJMVUpNQ1kG X-HM-Tid: 0a5306af0c956427691ee1101355 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org -------- Original Message -------- > Hi, > > Since about 4.4, we've been seeing reports of this warning on every boot > from some users: > > WARNING: CPU: 2 PID: 1 at drivers/iommu/amd_iommu_init.c:2301 > amd_iommu_pc_get_set_reg_val+0xa8/0xe0() > Modules linked in: > CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.4.2-300.fc23.x86_64 #1 > Hardware name: Hewlett-Packard HP EliteBook 755 G2/221C, BIOS M84 Ver. > 01.10 10/20/2015 > 0000000000000000 0000000026124b43 ffff88042d687d20 ffffffff813b0c9f > 0000000000000000 ffff88042d687d58 ffffffff810a2f12 ffff88042f014800 > 0000000000000040 0000000000000000 ffffffff81d6c73d 0000000000000000 > Call Trace: > [] dump_stack+0x44/0x55 > [] warn_slowpath_common+0x82/0xc0 > [] ? memblock_find_dma_reserve+0x16a/0x16a > [] warn_slowpath_null+0x1a/0x20 > [] amd_iommu_pc_get_set_reg_val+0xa8/0xe0 > [] iommu_go_to_state+0x4d6/0x1384 > [] ? kvasprintf+0x7a/0xa0 > [] ? memblock_find_dma_reserve+0x16a/0x16a > [] amd_iommu_init+0x13/0x201 > [] pci_iommu_init+0x12/0x3c > [] do_one_initcall+0xb3/0x200 > [] ? parse_args+0x295/0x4b0 > [] kernel_init_freeable+0x189/0x223 > [] ? rest_init+0x80/0x80 > [] kernel_init+0xe/0xe0 > [] ret_from_fork+0x3f/0x70 > [] ? rest_init+0x80/0x80 > > Full bugzilla https://bugzilla.redhat.com/show_bug.cgi?id=1310258 > > Any idea what might be causing this spew? I also see this warning. Suravee's the one of this patch series might be fix this issue, you can try it. [PATCH V4 0/6] perf/amd/iommu: Enable multi-IOMMU support > > Thanks, > Laura > _______________________________________________ > iommu mailing list > iommu@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/iommu >