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 A89A8EB64DA for ; Tue, 18 Jul 2023 08:56:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230231AbjGRI4X convert rfc822-to-8bit (ORCPT ); Tue, 18 Jul 2023 04:56:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40920 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229646AbjGRI4W (ORCPT ); Tue, 18 Jul 2023 04:56:22 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20AFAFA; Tue, 18 Jul 2023 01:56:21 -0700 (PDT) Received: from dggpemm500002.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4R4t7N6L92zVjfM; Tue, 18 Jul 2023 16:54:56 +0800 (CST) Received: from lhrpeml500005.china.huawei.com (7.191.163.240) by dggpemm500002.china.huawei.com (7.185.36.229) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Tue, 18 Jul 2023 16:56:18 +0800 Received: from lhrpeml500005.china.huawei.com ([7.191.163.240]) by lhrpeml500005.china.huawei.com ([7.191.163.240]) with mapi id 15.01.2507.027; Tue, 18 Jul 2023 09:56:16 +0100 From: Shameerali Kolothum Thodi To: Lorenzo Pieralisi , Guanghui Feng CC: "Guohanjun (Hanjun Guo)" , "sudeep.holla@arm.com" , "rafael@kernel.org" , "linux-acpi@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "baolin.wang@linux.alibaba.com" , "alikernel-developer@linux.alibaba.com" , "will@kernel.org" , "catalin.marinas@arm.com" Subject: RE: [PATCH v3] ACPI/IORT: Remove erroneous id_count check in iort_node_get_rmr_info() Thread-Topic: [PATCH v3] ACPI/IORT: Remove erroneous id_count check in iort_node_get_rmr_info() Thread-Index: AQHZuKLr8euEVepDckqwBEutSR/J0q+/F3qAgAAhwnA= Date: Tue, 18 Jul 2023 08:56:16 +0000 Message-ID: <597f481b0e5149dabe4821ca618af6b3@huawei.com> References: <1689593625-45213-1-git-send-email-guanghuifeng@linux.alibaba.com> In-Reply-To: Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.202.227.178] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org > -----Original Message----- > From: Lorenzo Pieralisi [mailto:lpieralisi@kernel.org] > Sent: 18 July 2023 08:52 > To: Guanghui Feng > Cc: Guohanjun (Hanjun Guo) ; > sudeep.holla@arm.com; rafael@kernel.org; linux-acpi@vger.kernel.org; > linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org; > baolin.wang@linux.alibaba.com; alikernel-developer@linux.alibaba.com; > will@kernel.org; catalin.marinas@arm.com; Shameerali Kolothum Thodi > > Subject: Re: [PATCH v3] ACPI/IORT: Remove erroneous id_count check in > iort_node_get_rmr_info() > > [+Catalin, Will, Shameer] > > On Mon, Jul 17, 2023 at 07:33:45PM +0800, Guanghui Feng wrote: > > According to the ARM IORT specifications DEN 0049 issue E, > > the "Number of IDs" field in the ID mapping format reports > > the number of IDs in the mapping range minus one. > > > > In iort_node_get_rmr_info(), we erroneously skip ID mappings > > whose "Number of IDs" equal to 0, resulting in valid mapping > > nodes with a single ID to map being skipped, which is wrong. > > > > Fix iort_node_get_rmr_info() by removing the bogus id_count > > check. > > > > Fixes: 491cf4a6735a ("ACPI/IORT: Add support to retrieve IORT RMR > reserved regions") > > Signed-off-by: Guanghui Feng > > --- > > drivers/acpi/arm64/iort.c | 3 --- > > 1 file changed, 3 deletions(-) > > > > diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c > > index 3631230..56d8873 100644 > > --- a/drivers/acpi/arm64/iort.c > > +++ b/drivers/acpi/arm64/iort.c > > @@ -1007,9 +1007,6 @@ static void iort_node_get_rmr_info(struct > acpi_iort_node *node, > > for (i = 0; i < node->mapping_count; i++, map++) { > > struct acpi_iort_node *parent; > > > > - if (!map->id_count) > > - continue; > > - > > parent = ACPI_ADD_PTR(struct acpi_iort_node, iort_table, > > map->output_reference); > > if (parent != iommu) > > Shameer, I know this may look like overkill since the hunk we are > removing is buggy but can you please test this patch on platforms > with RMR to make sure we are not triggering regressions by removing > it (by the specs that's what should be done but current firmware > is always something to reckon with) ? Yes, that is a valid fix. Unlikely it will be a problem. Anyway, I have requested Hanjun to help with the testing as I don't have a test setup with me now. Hanjun, please help. Thanks, Shameer