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=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 790D4C433E5 for ; Fri, 24 Jul 2020 19:54:24 +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 58002206F0 for ; Fri, 24 Jul 2020 19:54:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 58002206F0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=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 21C4A87255; Fri, 24 Jul 2020 19:54:24 +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 gAmLqPcCTCjA; Fri, 24 Jul 2020 19:54:23 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id 57C3487216; Fri, 24 Jul 2020 19:54:23 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 45C85C004D; Fri, 24 Jul 2020 19:54:23 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 0CBA7C004C for ; Fri, 24 Jul 2020 19:54:22 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id D7D5488B38 for ; Fri, 24 Jul 2020 19:54:21 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id u8AaQVl9VfNd for ; Fri, 24 Jul 2020 19:54:21 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by whitealder.osuosl.org (Postfix) with ESMTPS id 60BCB88B21 for ; Fri, 24 Jul 2020 19:54:21 +0000 (UTC) IronPort-SDR: juIc1f10A5opSb1dSROe2qaEe0ocyViilYQqEhLai4RG6ka9Htav4vDCst2vqMsDErd9nFQpEk u715ecjxZqfw== X-IronPort-AV: E=McAfee;i="6000,8403,9692"; a="235646610" X-IronPort-AV: E=Sophos;i="5.75,391,1589266800"; d="scan'208";a="235646610" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Jul 2020 12:54:21 -0700 IronPort-SDR: DESuWc6tXITsoJeaEjvblGe9pYncYoEAf0LSq/T+qLX4Z1qYxMiNCTthTHfMwAVcj1FLlo9E/O oG6mrGCuCmfg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,391,1589266800"; d="scan'208";a="433183920" Received: from sai-dev-mach.sc.intel.com ([143.183.140.153]) by orsmga004.jf.intel.com with ESMTP; 24 Jul 2020 12:54:20 -0700 From: Sai Praneeth Prakhya To: iommu@lists.linux-foundation.org, joro@8bytes.org Subject: [PATCH V5 3/3] iommu: Document usage of "/sys/kernel/iommu_groups//type" file Date: Fri, 24 Jul 2020 12:52:00 -0700 Message-Id: <59f594421615152012df9555362261b03eef3d1b.1595619936.git.sai.praneeth.prakhya@intel.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: References: MIME-Version: 1.0 Cc: Ashok Raj , Will Deacon , 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-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" The default domain type of an iommu group can be changed by writing to "/sys/kernel/iommu_groups//type" file. Hence, document it's usage and more importantly spell out its limitations. Cc: Christoph Hellwig Cc: Joerg Roedel Cc: Ashok Raj Cc: Will Deacon Cc: Lu Baolu Cc: Sohil Mehta Cc: Robin Murphy Cc: Jacob Pan Reviewed-by: Lu Baolu Signed-off-by: Sai Praneeth Prakhya --- .../ABI/testing/sysfs-kernel-iommu_groups | 30 +++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-kernel-iommu_groups b/Documentation/ABI/testing/sysfs-kernel-iommu_groups index 017f5bc3920c..5b50f0ddd2a1 100644 --- a/Documentation/ABI/testing/sysfs-kernel-iommu_groups +++ b/Documentation/ABI/testing/sysfs-kernel-iommu_groups @@ -33,3 +33,33 @@ Description: In case an RMRR is used only by graphics or USB devices it is now exposed as "direct-relaxable" instead of "direct". In device assignment use case, for instance, those RMRR are considered to be relaxable and safe. + +What: /sys/kernel/iommu_groups//type +Date: August 2020 +KernelVersion: v5.9 +Contact: Sai Praneeth Prakhya +Description: Let the user know the type of default domain in use by iommu + for this group. A privileged user could request kernel to change + the group type by writing to this file. Presently, only three + types are supported + 1. DMA: All the DMA transactions from the device in this group + are translated by the iommu. + 2. identity: All the DMA transactions from the device in this + group are *not* translated by the iommu. + 3. auto: Change to the type the device was booted with. When the + user reads the file he would never see "auto". This is + just a write only value. + Note: + ----- + A group type could be modified only when + 1. The group has *only* one device + 2. The device in the group is not bound to any device driver. + So, the user must first unbind the appropriate driver and + then change the default domain type. + Caution: + -------- + Unbinding a device driver will take away the driver's control + over the device and if done on devices that host root file + system could lead to catastrophic effects (the user might + need to reboot the machine to get it to normal state). So, it's + expected that the user understands what he is doing. -- 2.19.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu 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=-10.6 required=3.0 tests=BAYES_00, DATE_IN_FUTURE_48_96,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 6ABF3C433DF for ; Sat, 22 Aug 2020 04:03:53 +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 4948620732 for ; Sat, 22 Aug 2020 04:03:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4948620732 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=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 389E885F35; Sat, 22 Aug 2020 04:03:53 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id i_mhuqxYN8OH; Sat, 22 Aug 2020 04:03:52 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id 9D7E686248; Sat, 22 Aug 2020 04:03:51 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 8A248C0890; Sat, 22 Aug 2020 04:03:51 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 423D4C0051 for ; Sat, 22 Aug 2020 04:03:50 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 322BC85F0E for ; Sat, 22 Aug 2020 04:03:50 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Nj63RDdeXEBP for ; Sat, 22 Aug 2020 04:03:49 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by fraxinus.osuosl.org (Postfix) with ESMTPS id 9C4B785EF0 for ; Sat, 22 Aug 2020 04:03:49 +0000 (UTC) IronPort-SDR: Yk1SWGzRFNheVO25bY3quyCSkja204Boz/YxI1gFOsvYjnvzrO4YYvOqwGg+kCoU+HkhdJOoj9 lV3D106l/rRw== X-IronPort-AV: E=McAfee;i="6000,8403,9720"; a="240497827" X-IronPort-AV: E=Sophos;i="5.76,339,1592895600"; d="scan'208";a="240497827" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Aug 2020 21:03:49 -0700 IronPort-SDR: zZFW2T9KvPhqEGXWnyv6F3815ZvhuknzJAilH8LmVYHbkQ9FmXEJUiVObXeDDJZUvMpnCwwZe1 qkr1iduWSPkw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.76,339,1592895600"; d="scan'208";a="298135856" Received: from purley-4s.sc.intel.com ([172.25.112.112]) by orsmga006.jf.intel.com with ESMTP; 21 Aug 2020 21:03:49 -0700 From: Sai Praneeth Prakhya To: iommu@lists.linux-foundation.org Subject: [PATCH V6 3/3] iommu: Document usage of "/sys/kernel/iommu_groups//type" file Date: Sun, 23 Aug 2020 22:17:28 -0700 Message-ID: <59f594421615152012df9555362261b03eef3d1b.1595619936.git.sai.praneeth.prakhya@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: References: In-Reply-To: References: Cc: Ashok Raj , Will Deacon , 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: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Message-ID: <20200824051728.n1XgB9qMKxjKUrZwqEaPUKITrFHPEmvJP8gysOWzGR4@z> The default domain type of an iommu group can be changed by writing to "/sys/kernel/iommu_groups//type" file. Hence, document it's usage and more importantly spell out its limitations. Cc: Christoph Hellwig Cc: Joerg Roedel Cc: Ashok Raj Cc: Will Deacon Cc: Lu Baolu Cc: Sohil Mehta Cc: Robin Murphy Cc: Jacob Pan Reviewed-by: Lu Baolu Signed-off-by: Sai Praneeth Prakhya --- .../ABI/testing/sysfs-kernel-iommu_groups | 30 +++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-kernel-iommu_groups b/Documentation/ABI/testing/sysfs-kernel-iommu_groups index 017f5bc3920c..5b50f0ddd2a1 100644 --- a/Documentation/ABI/testing/sysfs-kernel-iommu_groups +++ b/Documentation/ABI/testing/sysfs-kernel-iommu_groups @@ -33,3 +33,33 @@ Description: In case an RMRR is used only by graphics or USB devices it is now exposed as "direct-relaxable" instead of "direct". In device assignment use case, for instance, those RMRR are considered to be relaxable and safe. + +What: /sys/kernel/iommu_groups//type +Date: August 2020 +KernelVersion: v5.9 +Contact: Sai Praneeth Prakhya +Description: Let the user know the type of default domain in use by iommu + for this group. A privileged user could request kernel to change + the group type by writing to this file. Presently, only three + types are supported + 1. DMA: All the DMA transactions from the device in this group + are translated by the iommu. + 2. identity: All the DMA transactions from the device in this + group are *not* translated by the iommu. + 3. auto: Change to the type the device was booted with. When the + user reads the file he would never see "auto". This is + just a write only value. + Note: + ----- + A group type could be modified only when + 1. The group has *only* one device + 2. The device in the group is not bound to any device driver. + So, the user must first unbind the appropriate driver and + then change the default domain type. + Caution: + -------- + Unbinding a device driver will take away the driver's control + over the device and if done on devices that host root file + system could lead to catastrophic effects (the user might + need to reboot the machine to get it to normal state). So, it's + expected that the user understands what he is doing. -- 2.19.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu 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=-10.8 required=3.0 tests=BAYES_00, DATE_IN_FUTURE_48_96,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 42915C433E2 for ; Sun, 6 Sep 2020 02:41:57 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (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 DE27A20757 for ; Sun, 6 Sep 2020 02:41:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DE27A20757 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=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 silver.osuosl.org (Postfix) with ESMTP id BE64D22902; Sun, 6 Sep 2020 02:41:56 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 7ReIy7GsEII9; Sun, 6 Sep 2020 02:41:53 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id CC86F22E8C; Sun, 6 Sep 2020 02:41:51 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id C66BBC0052; Sun, 6 Sep 2020 02:41:51 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 60406C0051 for ; Sun, 6 Sep 2020 02:41:49 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 5936286FE8 for ; Sun, 6 Sep 2020 02:41:49 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id HwPlWJMHMRbm for ; Sun, 6 Sep 2020 02:41:47 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by hemlock.osuosl.org (Postfix) with ESMTPS id 0E5BF87014 for ; Sun, 6 Sep 2020 02:41:47 +0000 (UTC) IronPort-SDR: SblZ+dyL3TdPa2ulavzMGbfKix9pEJVpb6Qw9OCE57+WhGzBZ7sBf7HlibqorFM8ECQNGSQMiz VbvJmliMJ47A== X-IronPort-AV: E=McAfee;i="6000,8403,9735"; a="137938310" X-IronPort-AV: E=Sophos;i="5.76,396,1592895600"; d="scan'208";a="137938310" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Sep 2020 19:41:46 -0700 IronPort-SDR: tqkbLPLrIlgCqZzxblOhRDpNb4SnS6uSpQPGu1yCADZ3PTwhevYFXeubv4Rf6rczgfdy3rcJM0 NBqfqv2sAlKw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.76,396,1592895600"; d="scan'208";a="340359287" Received: from purley-4s.sc.intel.com ([172.25.112.112]) by FMSMGA003.fm.intel.com with ESMTP; 05 Sep 2020 19:41:45 -0700 From: Sai Praneeth Prakhya To: iommu@lists.linux-foundation.org Subject: [PATCH V7 3/3] iommu: Document usage of "/sys/kernel/iommu_groups//type" file Date: Mon, 7 Sep 2020 20:54:47 -0700 Message-ID: <59f594421615152012df9555362261b03eef3d1b.1595619936.git.sai.praneeth.prakhya@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: References: In-Reply-To: References: Cc: Ashok Raj , Will Deacon , 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: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Message-ID: <20200908035447.ZzUHKRmd-p6yNwpONwt_afBVLSpvXhKT1aJ0ESqEULg@z> The default domain type of an iommu group can be changed by writing to "/sys/kernel/iommu_groups//type" file. Hence, document it's usage and more importantly spell out its limitations. Cc: Christoph Hellwig Cc: Joerg Roedel Cc: Ashok Raj Cc: Will Deacon Cc: Lu Baolu Cc: Sohil Mehta Cc: Robin Murphy Cc: Jacob Pan Reviewed-by: Lu Baolu Signed-off-by: Sai Praneeth Prakhya --- .../ABI/testing/sysfs-kernel-iommu_groups | 30 +++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-kernel-iommu_groups b/Documentation/ABI/testing/sysfs-kernel-iommu_groups index 017f5bc3920c..5b50f0ddd2a1 100644 --- a/Documentation/ABI/testing/sysfs-kernel-iommu_groups +++ b/Documentation/ABI/testing/sysfs-kernel-iommu_groups @@ -33,3 +33,33 @@ Description: In case an RMRR is used only by graphics or USB devices it is now exposed as "direct-relaxable" instead of "direct". In device assignment use case, for instance, those RMRR are considered to be relaxable and safe. + +What: /sys/kernel/iommu_groups//type +Date: September 2020 +KernelVersion: v5.10 +Contact: Sai Praneeth Prakhya +Description: Let the user know the type of default domain in use by iommu + for this group. A privileged user could request kernel to change + the group type by writing to this file. Presently, only three + types are supported + 1. DMA: All the DMA transactions from the device in this group + are translated by the iommu. + 2. identity: All the DMA transactions from the device in this + group are *not* translated by the iommu. + 3. auto: Change to the type the device was booted with. When the + user reads the file he would never see "auto". This is + just a write only value. + Note: + ----- + A group type could be modified only when + 1. The group has *only* one device + 2. The device in the group is not bound to any device driver. + So, the user must first unbind the appropriate driver and + then change the default domain type. + Caution: + -------- + Unbinding a device driver will take away the driver's control + over the device and if done on devices that host root file + system could lead to catastrophic effects (the user might + need to reboot the machine to get it to normal state). So, it's + expected that the user understands what he is doing. -- 2.19.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu