From mboxrd@z Thu Jan 1 00:00:00 1970 From: Don Dutile Subject: Re: [PATCH 1/2 V2] iommu/amd: Add workaround for ERBT1312 Date: Wed, 24 Apr 2013 09:52:40 -0400 Message-ID: <5177E3A8.5020001@redhat.com> References: <1366009666-44792-1-git-send-email-suravee.suthikulpanit@amd.com> <20130418160220.GA4153@8bytes.org> <51701B9F.10003@amd.com> <20130418162856.GA13891@8bytes.org> <51768B25.1060501@redhat.com> <20130424104616.GH17148@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20130424104616.GH17148-zLv9SwRftAIdnm+yROfE0A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Joerg Roedel Cc: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: iommu@lists.linux-foundation.org On 04/24/2013 06:46 AM, Joerg Roedel wrote: > On Tue, Apr 23, 2013 at 09:22:45AM -0400, Don Dutile wrote: >> Given other threads on this mail list (and I've seen crashes with same problem) >> where this type of logging during a flood of IOMMU errors will lock up the machine, >> is there something that can be done to break the do-while loop after n iterations >> have been exec'd, so the kernel can progress during a crash ? > > In the case of an IOMMU error flood this loop will only run until the > event-log/ppr-log overflows. So it should not turn into an endless loop. > > > Joerg > > Thanks for verification. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755718Ab3DXNwr (ORCPT ); Wed, 24 Apr 2013 09:52:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:30769 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753044Ab3DXNwq (ORCPT ); Wed, 24 Apr 2013 09:52:46 -0400 Message-ID: <5177E3A8.5020001@redhat.com> Date: Wed, 24 Apr 2013 09:52:40 -0400 From: Don Dutile User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.11) Gecko/20121116 Thunderbird/10.0.11 MIME-Version: 1.0 To: Joerg Roedel CC: Suravee Suthikulanit , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2 V2] iommu/amd: Add workaround for ERBT1312 References: <1366009666-44792-1-git-send-email-suravee.suthikulpanit@amd.com> <20130418160220.GA4153@8bytes.org> <51701B9F.10003@amd.com> <20130418162856.GA13891@8bytes.org> <51768B25.1060501@redhat.com> <20130424104616.GH17148@8bytes.org> In-Reply-To: <20130424104616.GH17148@8bytes.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/24/2013 06:46 AM, Joerg Roedel wrote: > On Tue, Apr 23, 2013 at 09:22:45AM -0400, Don Dutile wrote: >> Given other threads on this mail list (and I've seen crashes with same problem) >> where this type of logging during a flood of IOMMU errors will lock up the machine, >> is there something that can be done to break the do-while loop after n iterations >> have been exec'd, so the kernel can progress during a crash ? > > In the case of an IOMMU error flood this loop will only run until the > event-log/ppr-log overflows. So it should not turn into an endless loop. > > > Joerg > > Thanks for verification.