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=-15.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 581ABC2B9F4 for ; Mon, 14 Jun 2021 16:35:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2C73461245 for ; Mon, 14 Jun 2021 16:35:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234700AbhFNQhl (ORCPT ); Mon, 14 Jun 2021 12:37:41 -0400 Received: from frasgout.his.huawei.com ([185.176.79.56]:3239 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234470AbhFNQhk (ORCPT ); Mon, 14 Jun 2021 12:37:40 -0400 Received: from fraeml736-chm.china.huawei.com (unknown [172.18.147.206]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4G3cJS5k7wz6G8bn; Tue, 15 Jun 2021 00:26:00 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml736-chm.china.huawei.com (10.206.15.217) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Mon, 14 Jun 2021 18:35:36 +0200 Received: from [10.47.95.26] (10.47.95.26) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Mon, 14 Jun 2021 17:35:35 +0100 Subject: Re: [PATCH] iommu: Update "iommu.strict" documentation To: Robin Murphy , CC: , , , References: <2c8c06e1b449d6b060c5bf9ad3b403cd142f405d.1623682646.git.robin.murphy@arm.com> From: John Garry Message-ID: <1e95deac-b0c3-e122-f1e5-7748424a2c9f@huawei.com> Date: Mon, 14 Jun 2021 17:29:31 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.1.2 MIME-Version: 1.0 In-Reply-To: <2c8c06e1b449d6b060c5bf9ad3b403cd142f405d.1623682646.git.robin.murphy@arm.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.47.95.26] X-ClientProxiedBy: lhreml725-chm.china.huawei.com (10.201.108.76) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 14/06/2021 15:57, Robin Murphy wrote: > Consolidating the flush queue logic also meant that the "iommu.strict" > option started taking effect on x86 as well. Make sure we document that. > > Fixes: a250c23f15c2 ("iommu: remove DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE") > Signed-off-by: Robin Murphy I assumed that all bets were off when we use a cmdline param which is not "officially" supported. Anyway, FWIW: Reviewed-by: John Garry > --- > Documentation/admin-guide/kernel-parameters.txt | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index cb89dbdedc46..20a32de990ed 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -1987,7 +1987,7 @@ > forcing Dual Address Cycle for PCI cards supporting > greater than 32-bit addressing. > > - iommu.strict= [ARM64] Configure TLB invalidation behaviour > + iommu.strict= [ARM64, X86] Configure TLB invalidation behaviour > Format: { "0" | "1" } > 0 - Lazy mode. > Request that DMA unmap operations use deferred