Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932296Ab3DBOf0 (ORCPT ); Tue, 2 Apr 2013 10:35:26 -0400 Received: from 8bytes.org ([85.214.48.195]:53735 "EHLO mail.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932084Ab3DBOfY (ORCPT ); Tue, 2 Apr 2013 10:35:24 -0400 Date: Tue, 2 Apr 2013 16:35:22 +0200 From: Joerg Roedel To: suravee.suthikulpanit@amd.com Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/3] iommu/amd: Add IOMMU event log injection interface for testing event flag decoding logic Message-ID: <20130402143521.GC15687@8bytes.org> References: <1364428294-2579-1-git-send-email-suravee.suthikulpanit@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1364428294-2579-1-git-send-email-suravee.suthikulpanit@amd.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-DSPAM-Result: Whitelisted X-DSPAM-Processed: Tue Apr 2 16:35:23 2013 X-DSPAM-Confidence: 0.9989 X-DSPAM-Probability: 0.0000 X-DSPAM-Signature: 515aecab23671893720817 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1179 Lines: 26 On Wed, Mar 27, 2013 at 06:51:34PM -0500, suravee.suthikulpanit@amd.com wrote: > From: Suravee Suthikulpanit > > Add IOMMU event log injection interface for testing event flag decoding logic. > This interface allows users to specify device id, event flag, and event types via debugfs. > > echo 0x300 > /sys/kernel/debug/amd-iommu-evninj/devid // (e.g. Bus:Dev.fun 3:0.0) > echo 0xfff > /sys/kernel/debug/amd-iommu-evninj/flags // (e.g. Specify flag value) > echo 2 > /sys/kernel/debug/amd-iommu-evninj/type // (e.g. for IO_PAGE_FAULT event) > > Once the event is injected, IOMMU driver will parse and print out the event information > in kernel log (dmesg) with the various information depending on the types of event and flag > specified. Why is this needed? I think the risk of regressions in the event-handling code is to low to justify the need for an event-injection mechanism. 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/