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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 85BD0C433F5 for ; Fri, 25 Feb 2022 22:06:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234622AbiBYWHK (ORCPT ); Fri, 25 Feb 2022 17:07:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59698 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230052AbiBYWHF (ORCPT ); Fri, 25 Feb 2022 17:07:05 -0500 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9AE401F636C for ; Fri, 25 Feb 2022 14:06:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1645826792; x=1677362792; h=date:from:to:cc:subject:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=U0LnNa5rgaykiuNGMZGPVXAMkCcNVFd2QMGGkX2fDMc=; b=fW/WVDVrg2g4JRNkndn9IdZ0zyybZ6MUeMWiGv45/u32zWaVtmgK58Tz OVUed07z9k4glq8qGM6h6VmS85PYJMPXXQWXXNwvjOl0RgLN34Xf1rbXc 6WahMQm7ZdfTv6iDEXhmjq3NAsFuiu/U0ww33zjFtTr+mDcJqvTdjR93w HTFgnnsBYqONRtnWTdzzg/QShoU/FzU9c+7bYsc41GDmNmGtmhf3MhZ1w Xok+ZlqtYlkTiYjMp42Ezs7Qg6/zUqMHoEmVFjmwQrbnHd9bw7umv3ymq sO2WYzTZUpXQ5GFo0CfV4vNUEjzhXikJXMsztwpJXHKhoycWSKbmv0CgQ A==; X-IronPort-AV: E=McAfee;i="6200,9189,10269"; a="233214070" X-IronPort-AV: E=Sophos;i="5.90,137,1643702400"; d="scan'208";a="233214070" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Feb 2022 14:06:32 -0800 X-IronPort-AV: E=Sophos;i="5.90,137,1643702400"; d="scan'208";a="684776647" Received: from jacob-builder.jf.intel.com (HELO jacob-builder) ([10.7.198.157]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Feb 2022 14:06:32 -0800 Date: Fri, 25 Feb 2022 14:09:37 -0800 From: Jacob Pan To: Lu Baolu Cc: Joerg Roedel , Kevin Tian , Ashok Raj , Liu Yi L , Robin Murphy , Jason Gunthorpe , Christoph Hellwig , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, jacob.jun.pan@linux.intel.com Subject: Re: [PATCH v1 09/10] iommu/vt-d: Refactor dmar_insert_one_dev_info() Message-ID: <20220225140617.63a95344@jacob-builder> In-Reply-To: <20220207064142.1092846-10-baolu.lu@linux.intel.com> References: <20220207064142.1092846-1-baolu.lu@linux.intel.com> <20220207064142.1092846-10-baolu.lu@linux.intel.com> Organization: OTC X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi BaoLu, On Mon, 7 Feb 2022 14:41:41 +0800, Lu Baolu wrote: > > - if (dev && domain_context_mapping(domain, dev)) { > - dev_err(dev, "Domain context map failed\n"); > - dmar_remove_one_dev_info(dev); > - return NULL; > - } > + /* Setup the context entry for device: */ > + ret = domain_context_mapping(domain, dev); > + if (ret) > + goto setup_context_err; > > - return domain; > + info->domain = domain; > + list_add_rcu(&info->link, &domain->devices); > + There seems to be an ordering problem. We need to do list_add_rcu() *before* domain_context_mapping(). Otherwise, while doing context mapping the search for dev IOTLB support in iommu_support_dev_iotlb() will fail. Then ATS capable device context will not have DTE bit set. The result is DMAR unrecoverable fault while doing DMA. Thanks, Jacob