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=-5.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,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 83E0CC47082 for ; Tue, 1 Jun 2021 03:10:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60EAC610E7 for ; Tue, 1 Jun 2021 03:10:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232725AbhFADLs (ORCPT ); Mon, 31 May 2021 23:11:48 -0400 Received: from mga11.intel.com ([192.55.52.93]:61872 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232268AbhFADLq (ORCPT ); Mon, 31 May 2021 23:11:46 -0400 IronPort-SDR: srMUuq/4w0gJiKhUaG4NWJWKp9mWyv7LwGCGrC6/dHXPxb9164XJ7pagcSlfET2DdfjMuu8bW5 CPQegpieqZNg== X-IronPort-AV: E=McAfee;i="6200,9189,10001"; a="200446690" X-IronPort-AV: E=Sophos;i="5.83,239,1616482800"; d="scan'208";a="200446690" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 May 2021 20:10:04 -0700 IronPort-SDR: ULzOL29Vz/IvsNNwQwQA6U77N3rMZEqYfgfyjQyFc8zsTXp9NGuDPeuj9u/nToeVpAZVE4iwh8 yIPDfw8wzWLg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.83,239,1616482800"; d="scan'208";a="632725264" Received: from allen-box.sh.intel.com (HELO [10.239.159.105]) ([10.239.159.105]) by fmsmga006.fm.intel.com with ESMTP; 31 May 2021 20:10:01 -0700 Cc: baolu.lu@linux.intel.com, Jean-Philippe Brucker , "Tian, Kevin" , "Jiang, Dave" , "Raj, Ashok" , "kvm@vger.kernel.org" , Jonathan Corbet , David Woodhouse , Jason Wang , LKML , Kirti Wankhede , "Alex Williamson (alex.williamson@redhat.com)" , "iommu@lists.linux-foundation.org" , Robin Murphy , David Gibson Subject: Re: [RFC] /dev/ioasid uAPI proposal To: Jason Gunthorpe , Liu Yi L References: <20210528233649.GB3816344@nvidia.com> <20210531193157.5494e6c6@yiliu-dev> <20210531180911.GX1002214@nvidia.com> From: Lu Baolu Message-ID: <6ca65628-1c0e-4ae3-6357-1493f993349e@linux.intel.com> Date: Tue, 1 Jun 2021 11:08:53 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <20210531180911.GX1002214@nvidia.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/1/21 2:09 AM, Jason Gunthorpe wrote: >>> device bind should fail if the device somehow isn't compatible with >>> the scheme the user is tring to use. >> yeah, I guess you mean to fail the device attach when the IOASID is a >> nesting IOASID but the device is behind an iommu without nesting support. >> right? > Right.. > Just want to confirm... Does this mean that we only support hardware nesting and don't want to have soft nesting (shadowed page table in kernel) in IOASID? Best regards, baolu