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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 2D3D3FA372C for ; Fri, 8 Nov 2019 16:17:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EFB3821D6C for ; Fri, 8 Nov 2019 16:17:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726651AbfKHQRt (ORCPT ); Fri, 8 Nov 2019 11:17:49 -0500 Received: from lhrrgout.huawei.com ([185.176.76.210]:2077 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725941AbfKHQRs (ORCPT ); Fri, 8 Nov 2019 11:17:48 -0500 Received: from LHREML710-CAH.china.huawei.com (unknown [172.18.7.107]) by Forcepoint Email with ESMTP id 2D181470A7A6746D7EF5; Fri, 8 Nov 2019 16:17:47 +0000 (GMT) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by LHREML710-CAH.china.huawei.com (10.201.108.33) with Microsoft SMTP Server (TLS) id 14.3.408.0; Fri, 8 Nov 2019 16:17:46 +0000 Received: from [127.0.0.1] (10.202.226.46) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.1713.5; Fri, 8 Nov 2019 16:17:46 +0000 Subject: Re: [PATCH v2 6/9] Revert "iommu/arm-smmu: Make arm-smmu-v3 explicitly non-modular" To: Will Deacon , , CC: Jean-Philippe Brucker , Jordan Crouse , Bjorn Helgaas , "Saravana Kannan" , "Isaac J. Manjarres" , Robin Murphy , Lorenzo Pieralisi , Joerg Roedel References: <20191108151608.20932-1-will@kernel.org> <20191108151608.20932-7-will@kernel.org> From: John Garry Message-ID: <06dfd385-1af0-3106-4cc5-6a5b8e864759@huawei.com> Date: Fri, 8 Nov 2019 16:17:45 +0000 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: <20191108151608.20932-7-will@kernel.org> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.226.46] X-ClientProxiedBy: lhreml703-chm.china.huawei.com (10.201.108.52) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/11/2019 15:16, Will Deacon wrote: > +MODULE_DEVICE_TABLE(of, arm_smmu_of_match); Hi Will, > > static struct platform_driver arm_smmu_driver = { > .driver = { > .name = "arm-smmu-v3", > .of_match_table = of_match_ptr(arm_smmu_of_match), > - .suppress_bind_attrs = true, Does this mean that we can now manually unbind this driver from the SMMU device? Seems dangerous. Here's what happens for me: root@ubuntu:/sys# cd ./bus/platform/drivers/arm-smmu-v3 ind @ubuntu:/sys/bus/platform/drivers/arm-smmu-v3# echo arm-smmu-v3.0.auto > unbind [ 77.580351] hisi_sas_v2_hw HISI0162:01: CQE_AXI_W_ERR (0x800) found! ho [ 78.635473] platform arm-smmu-v3.0.auto: CMD_SYNC timeout at 0x00000146 [hwprod 0x00000146, hwcons 0x00000000] > }, > .probe = arm_smmu_device_probe, > + .remove = arm_smmu_device_remove, > .shutdown = arm_smmu_device_shutdown, > }; > -builtin_platform_driver(arm_smmu_driver); > +module_platform_driver(arm_smmu_driver); > + Thanks, John