From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 387F6C388F9 for ; Fri, 20 Nov 2020 02:20:28 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 88D442225E for ; Fri, 20 Nov 2020 02:20:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 88D442225E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 0470B86D78; Fri, 20 Nov 2020 02:20:27 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id w3mdakllhSc5; Fri, 20 Nov 2020 02:20:25 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id 9782D86D08; Fri, 20 Nov 2020 02:20:25 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 8B056C1825; Fri, 20 Nov 2020 02:20:25 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists.linuxfoundation.org (Postfix) with ESMTP id 96F27C0891 for ; Fri, 20 Nov 2020 02:20:24 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id 7A395203F3 for ; Fri, 20 Nov 2020 02:20:24 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id mXNn6DP9TyiF for ; Fri, 20 Nov 2020 02:20:22 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by silver.osuosl.org (Postfix) with ESMTPS id DC4631FC71 for ; Fri, 20 Nov 2020 02:20:21 +0000 (UTC) IronPort-SDR: RBFj+OR8j1TcxUII0B18jSolp3COCwdzmPUDWRkS628asIY9vwz+sy8K4M10E6D6vivbmkHz+6 QcfKBED/pKNA== X-IronPort-AV: E=McAfee;i="6000,8403,9810"; a="158439151" X-IronPort-AV: E=Sophos;i="5.78,354,1599548400"; d="scan'208";a="158439151" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Nov 2020 18:20:21 -0800 IronPort-SDR: xt3/am10qXx+QJZeUjl3U9pdvg23WlP0jWA6zWN9RlOM4lgb1P4f+O5ptqZmbhIi+UtUbE6K8V emJkv5yQqdyA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.78,354,1599548400"; d="scan'208";a="431430496" Received: from allen-box.sh.intel.com (HELO [10.239.159.28]) ([10.239.159.28]) by fmsmga001.fm.intel.com with ESMTP; 19 Nov 2020 18:20:19 -0800 Subject: Re: [Patch V8 3/3] iommu: Document usage of "/sys/kernel/iommu_groups//type" file To: Will Deacon References: <20200925190620.18732-1-ashok.raj@intel.com> <20200925190620.18732-4-ashok.raj@intel.com> <20201118135137.GA2177@willie-the-truck> <7eeae289-070f-c5c9-aff5-edbb8437ef69@linux.intel.com> <20201119085529.GB3599@willie-the-truck> From: Lu Baolu Message-ID: <918cf2d0-91b7-b1f1-3859-88615acbbb1c@linux.intel.com> Date: Fri, 20 Nov 2020 10:13:09 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20201119085529.GB3599@willie-the-truck> Content-Language: en-US Cc: Ashok Raj , Will Deacon , iommu@lists.linux-foundation.org, Robin Murphy , Christoph Hellwig X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Hi Will On 11/19/20 4:55 PM, Will Deacon wrote: > Hi Lu, > > On Thu, Nov 19, 2020 at 10:32:43AM +0800, Lu Baolu wrote: >> On 11/18/20 9:51 PM, Will Deacon wrote: >>> On Fri, Sep 25, 2020 at 12:06:20PM -0700, Ashok Raj wrote: >>> I can't figure out from this description what string is returned to >>> userspace in the case that the group is configured as blocked or unmanaged. >> >> This series only enables switching a default domain in use between DMA >> and IDENTITY. Other cases will result in write failures. > > I understood that from the text, but what I couldn't figure out is what > happens if you *read* the file when the default domain is not identity > or DMA. I think that should be documented. Yes, agreed. I will add this. Best regards, baolu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu