From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751209AbeC2IuV (ORCPT ); Thu, 29 Mar 2018 04:50:21 -0400 Received: from 8bytes.org ([81.169.241.247]:44798 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750707AbeC2IuU (ORCPT ); Thu, 29 Mar 2018 04:50:20 -0400 Date: Thu, 29 Mar 2018 10:50:18 +0200 From: Joerg Roedel To: Dmitry Safonov Cc: linux-kernel@vger.kernel.org, 0x7f454c46@gmail.com, Alex Williamson , David Woodhouse , Ingo Molnar , Lu Baolu , iommu@lists.linux-foundation.org Subject: Re: [PATCHv3] iommu/intel: Ratelimit each dmar fault printing Message-ID: <20180329085017.tkdtx77u4khiuqhw@8bytes.org> References: <20180215191729.15777-1-dima@arista.com> <20180315134649.skh2aukcmg5ud74y@8bytes.org> <1521123183.2686.7.camel@arista.com> <20180315142253.GC5259@8bytes.org> <1521124490.2686.16.camel@arista.com> <1521124920.2686.20.camel@arista.com> <20180315152828.GA11365@8bytes.org> <1521579013.2686.83.camel@arista.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1521579013.2686.83.camel@arista.com> User-Agent: NeoMutt/20170421 (1.8.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 20, 2018 at 08:50:13PM +0000, Dmitry Safonov wrote: > Hmm, but this fixes my softlockup issue, because it's about time spent > in printk() inside irq-disabled section, rather about exiting the dmar- > clearing loop. > And on my hw doesn't make any difference to limit loop or not because > clearing a fault is much faster than hw could generate a new fault. > ITOW, it fixes the softlockup for me and the loop-related lockup can't > happen on hw I have (so it's the other issue, [possible?] on other hw). It might solve your issue, but someone else might still run into it with a different setup. An upstream fix needs to solve it for everyone. Thanks, Joerg