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 42D65EB64DA for ; Tue, 18 Jul 2023 07:52:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231489AbjGRHw0 (ORCPT ); Tue, 18 Jul 2023 03:52:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56728 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231493AbjGRHwX (ORCPT ); Tue, 18 Jul 2023 03:52:23 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DD8548E; Tue, 18 Jul 2023 00:52:18 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7C90961446; Tue, 18 Jul 2023 07:52:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1B45C433C8; Tue, 18 Jul 2023 07:52:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1689666737; bh=OBIHH19P1Xzv4nT4f72NuFolXMnRwud9KX0ascqhx6o=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=n4ucQaTnl9zSPNxYU4ZSfeUQZA3KFQTrhy3oPIlUui3lm5knFedsm0obdxqSfTKMV rxx6V9SJdIZQ0u4eRlkIpZQsev1VLhd3Flvh2LQg+alYJCHvR0ZCSEk0TGYEoEUn1L Ak6MAmhd7f2UJvgfecxdLU+0ByY54zS2xd9DVKrK2wi4Zo6QNGvUXFcp85ILLncsiA P1QhRWBuUUlcMKN/DsQepSQbOJWeE1Ocou32/3E1dxia/hu+v/dS2/+5blD2l49fAf oKXdu5IQ8F3ZZ9HhHMCWAiFq/umoH6e6NzfQoSPamAcYqwMW2JLsA+KXkS0LUy+njb tjgF40avqvLXw== Date: Tue, 18 Jul 2023 09:52:11 +0200 From: Lorenzo Pieralisi To: Guanghui Feng Cc: guohanjun@huawei.com, 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@huawei.com Subject: Re: [PATCH v3] ACPI/IORT: Remove erroneous id_count check in iort_node_get_rmr_info() Message-ID: References: <1689593625-45213-1-git-send-email-guanghuifeng@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1689593625-45213-1-git-send-email-guanghuifeng@linux.alibaba.com> Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org [+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) ? Thanks, Lorenzo