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=-5.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 CD843C433E0 for ; Wed, 27 Jan 2021 07:38:10 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 6C96920663 for ; Wed, 27 Jan 2021 07:38:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6C96920663 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ZQZdyOfY17+SoA1Ir1Nf2J+lWSAVjSSAECjCKuo/Oeg=; b=dfpbHn10cUhJNgpEZLgd82+Ig UXZ6ClMbqeAbAQ/oVo7AUqorLzns5zeRqYlnyKNN6bteCWpkw9nHEc1uKZQWdi6Nce3bfwaCSU89V qoEdizjORzte5qgmcerVBpSlzxgqrsRU62PEp/PHo7Z/M+lKGuaLlE+kpt/AuTRmWBFFW8i+1lvEk 9y7aR07dmUrvtSdWHaKOIRk0N0VeaGqI1gVv6JgpIZd6PofPIaf3rr3Xraz6w/2FK99ckI89MLgT6 kMHIbljo2IZR+sE+ZxXN0WXileZZ/bWkpLPDs/WylLmKxT1ZO6WJbRU7nYbiGpQqKKx1s8iKzbu5K KNtvuOicQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l4fNQ-0007lm-4Z; Wed, 27 Jan 2021 07:36:32 +0000 Received: from szxga06-in.huawei.com ([45.249.212.32]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l4fNN-0007l6-8k for linux-arm-kernel@lists.infradead.org; Wed, 27 Jan 2021 07:36:30 +0000 Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4DQb3s05f2zjCv3; Wed, 27 Jan 2021 15:35:21 +0800 (CST) Received: from [10.174.184.42] (10.174.184.42) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.498.0; Wed, 27 Jan 2021 15:36:09 +0800 Subject: Re: [PATCH 1/1] iommu/arm-smmu-v3: add support for BBML To: Will Deacon , Robin Murphy References: <20201126034230.777-1-thunder.leizhen@huawei.com> <20210122125132.GB24102@willie-the-truck> <1bfd1ca0-953e-e943-f87e-144d5537bd0c@arm.com> <20210126101230.GA29204@willie-the-truck> <8a9685ec-67aa-824f-5429-f408bf79c5ab@huawei.com> From: Keqian Zhu Message-ID: <32f4752f-6954-183a-a0c1-b5d719c85b67@huawei.com> Date: Wed, 27 Jan 2021 15:36:08 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: <8a9685ec-67aa-824f-5429-f408bf79c5ab@huawei.com> X-Originating-IP: [10.174.184.42] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210127_023629_553641_DF520DF5 X-CRM114-Status: GOOD ( 15.21 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jean-Philippe Brucker , Joerg Roedel , "Leizhen \(ThunderTown\)" , linux-kernel , iommu , Jonathan Cameron , Yang Yingliang , linux-arm-kernel Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2021/1/27 10:01, Leizhen (ThunderTown) wrote: > > > On 2021/1/26 18:12, Will Deacon wrote: >> On Mon, Jan 25, 2021 at 08:23:40PM +0000, Robin Murphy wrote: >>> Now we probably will need some degreee of BBML feature awareness for the >>> sake of SVA if and when we start using it for CPU pagetables, but I still >>> cannot see any need to consider it in io-pgtable. >> >> Agreed; I don't think this is something that io-pgtable should have to care >> about. Hi, I have a question here :-). If the old table is not live, then the break procedure seems unnecessary. Do I miss something? Thanks, Keqian > > Yes, the SVA works in stall mode, and the failed device access requests are not > discarded. > > Let me look for examples. The BBML usage scenario was told by a former colleague. > >> >> Will >> >> . >> > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > . > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel