Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751803Ab3F1S3t (ORCPT ); Fri, 28 Jun 2013 14:29:49 -0400 Received: from 8bytes.org ([85.214.48.195]:47157 "EHLO mail.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751459Ab3F1S3r (ORCPT ); Fri, 28 Jun 2013 14:29:47 -0400 Date: Fri, 28 Jun 2013 20:29:46 +0200 From: Joerg Roedel To: Alex Williamson Cc: Andreas Hartmann , LKML Subject: Re: [ 102/127] iommu/amd: Workaround for ERBT1312 Message-ID: <20130628182946.GU11309@8bytes.org> References: <20130628181136.52d00e9c@dualc.maya.org> <1372441744.30572.765.camel@ul30vt.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1372441744.30572.765.camel@ul30vt.home> User-Agent: Mutt/1.5.21 (2010-09-15) X-DSPAM-Result: Whitelisted X-DSPAM-Processed: Fri Jun 28 20:29:46 2013 X-DSPAM-Confidence: 0.9974 X-DSPAM-Probability: 0.0000 X-DSPAM-Signature: 51cdd61a20861916217421 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1349 Lines: 35 Hi Alex, On Fri, Jun 28, 2013 at 11:49:04AM -0600, Alex Williamson wrote: > That's interesting, I PXE boot my system from one NIC then use a > different NIC for the iSCSI root. The PXE boot NIC now screams like > this, _until_ I attach it to vfio, then it quiets down. Can you please send an example line of the reported fault? The addresses it faults on would be interesting. > > Any idea? > > Not really without some digging. I wonder if it's a new event each time > or if something is just not clearing a previous event. ISTR that a boot > used to often, but not always, generate a couple faults between the > IOMMU being enabled and the NIC driver being loaded. All the faults I > see are to the same address, so my guess is that it's getting replayed. Well, I think it is a problem uncovered by the patch that re-enables the event-log interrupt after it happened once. We need to find a strategy to cope with those problems. To my mind as a quick-fix comes rate-limiting for the printks. Or we use the suppress-pf bit in the DTE to suppress all page-faults after the first one. Joerg -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/