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=-6.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 4218EC48BCF for ; Wed, 9 Jun 2021 09:01:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2378561181 for ; Wed, 9 Jun 2021 09:01:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237773AbhFIJDs (ORCPT ); Wed, 9 Jun 2021 05:03:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:49978 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231919AbhFIJDr (ORCPT ); Wed, 9 Jun 2021 05:03:47 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 26F6B6023B; Wed, 9 Jun 2021 09:01:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623229313; bh=Z+zI0RDuvSuYN6v7HJscpw3B4/5MAYapaANvzw9NBwc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WmiR2RPPVpg5P331nrK6XjeWdv7pCU0af80mG7uj4/EG2o1tb9LLtohiNLtk8mpOb tkFIKDCEKcOcSiIcbIMGVJ/fN1JUvOts/U/6Yw1l97gZt0kPZUy4edDI5lNpXcnIHC W5BeTbAVwtq/9WO1fN6mDJoad1oG+A8DlCM4IJCZshJ82bV4+vGfwQkfXHIYfjD0jV bEtrvNChyxo6+7hO+YhBAUjFIuWHPM3pjUlKGjLtPl/N1r55hfu6xP0Jm22i9rYpGC TnY9mjqjTBAMX7vHcjrSXqStZ8qiBPVsWNoI4f98t6nYhC5euToDZuG5VDhnF8mgAN QyqLZFfoTPMdQ== Date: Wed, 9 Jun 2021 12:01:49 +0300 From: Leon Romanovsky To: "Tian, Kevin" Cc: Jason Gunthorpe , "Alex Williamson (alex.williamson@redhat.com)" , Jean-Philippe Brucker , David Gibson , Jason Wang , "parav@mellanox.com" , "Enrico Weigelt, metux IT consult" , Paolo Bonzini , Shenming Lu , Eric Auger , Jonathan Corbet , "Raj, Ashok" , "Liu, Yi L" , "Wu, Hao" , "Jiang, Dave" , Jacob Pan , Kirti Wankhede , Robin Murphy , "kvm@vger.kernel.org" , "iommu@lists.linux-foundation.org" , David Woodhouse , Joerg Roedel , LKML , Lu Baolu Subject: Re: Plan for /dev/ioasid RFC v2 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 07, 2021 at 02:58:18AM +0000, Tian, Kevin wrote: > Hi, all, <...> > (Remaining opens in v1) <...> > - Device-centric (Jason) vs. group-centric (David) uAPI. David is not fully > convinced yet. Based on discussion v2 will continue to have ioasid uAPI > being device-centric (but it's fine for vfio to be group-centric). A new > section will be added to elaborate this part; <...> > (Adopted suggestions) <...> > - (Jason) Addition of device label allows per-device capability/format > check before IOASIDs are created. This leads to another major uAPI > change in v2 - specify format info when creating an IOASID (mapping > protocol, nesting, coherent, etc.). User is expected to check per-device > format and then set proper format for IOASID upon to-be-attached > device; Sorry for my naive question, I still didn't read all v1 thread and maybe the answer is already written, but will ask anyway. Doesn't this adopted suggestion to allow device-specific configuration actually means that uAPI should be device-centric? User already needs to be aware of device, configure it explicitly, maybe gracefully clean it later, it looks like not so much left to be group-centric. Thanks