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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 88084C35641 for ; Fri, 21 Feb 2020 08:32:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5970720578 for ; Fri, 21 Feb 2020 08:32:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582273955; bh=PCRHLSZbmJqJViTJ0dB1E8Xa4H57b8wOz/Mff5gZdes=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=XMDW+OccGrBVp3DOBFnoBm+o32box/fWJcNZCbJELPCus+BZ0IFcqo7mXSdK1NofN ZQupQbJ6H8aY5uqu5zafGfVUMOpJjk+6nwb8D/IvFEnPH4wir0o722bOgoovInQlIf 6ButY1qKOJb2PO6iE18vWXfmiQrQ4J0nQI9CeBd8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387582AbgBUIce (ORCPT ); Fri, 21 Feb 2020 03:32:34 -0500 Received: from mail.kernel.org ([198.145.29.99]:47974 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732797AbgBUIMQ (ORCPT ); Fri, 21 Feb 2020 03:12:16 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F0BF620722; Fri, 21 Feb 2020 08:12:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582272735; bh=PCRHLSZbmJqJViTJ0dB1E8Xa4H57b8wOz/Mff5gZdes=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YgJOhrcROnHoyABSAtFQsNAwhp3zn4wV3v0GebXOmuS4sC60auGgYcob3VgCbBdY4 6zotinC2jVmAAaj6lV+2ftEVZl187/uvEHDxvojmSwIPIh9m5xgBufnEj0F7WpzO7m zVpWJ+KClb1JiBj+JIMz8WLgffAH/UyNIUeRBaH8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Pankaj Bansal , Hanjun Guo , Lorenzo Pieralisi , Will Deacon , Sudeep Holla , Catalin Marinas , Robin Murphy , Sasha Levin Subject: [PATCH 5.4 254/344] ACPI/IORT: Fix Number of IDs handling in iort_id_map() Date: Fri, 21 Feb 2020 08:40:53 +0100 Message-Id: <20200221072412.606392874@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200221072349.335551332@linuxfoundation.org> References: <20200221072349.335551332@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Hanjun Guo [ Upstream commit 3c23b83a88d00383e1d498cfa515249aa2fe0238 ] The IORT specification [0] (Section 3, table 4, page 9) defines the 'Number of IDs' as 'The number of IDs in the range minus one'. However, the IORT ID mapping function iort_id_map() treats the 'Number of IDs' field as if it were the full IDs mapping count, with the following check in place to detect out of boundary input IDs: InputID >= Input base + Number of IDs This check is flawed in that it considers the 'Number of IDs' field as the full number of IDs mapping and disregards the 'minus one' from the IDs count. The correct check in iort_id_map() should be implemented as: InputID > Input base + Number of IDs this implements the specification correctly but unfortunately it breaks existing firmwares that erroneously set the 'Number of IDs' as the full IDs mapping count rather than IDs mapping count minus one. e.g. PCI hostbridge mapping entry 1: Input base: 0x1000 ID Count: 0x100 Output base: 0x1000 Output reference: 0xC4 //ITS reference PCI hostbridge mapping entry 2: Input base: 0x1100 ID Count: 0x100 Output base: 0x2000 Output reference: 0xD4 //ITS reference Two mapping entries which the second entry's Input base = the first entry's Input base + ID count, so for InputID 0x1100 and with the correct InputID check in place in iort_id_map() the kernel would map the InputID to ITS 0xC4 not 0xD4 as it would be expected. Therefore, to keep supporting existing flawed firmwares, introduce a workaround that instructs the kernel to use the old InputID range check logic in iort_id_map(), so that we can support both firmwares written with the flawed 'Number of IDs' logic and the correct one as defined in the specifications. [0]: http://infocenter.arm.com/help/topic/com.arm.doc.den0049d/DEN0049D_IO_Remapping_Table.pdf Reported-by: Pankaj Bansal Link: https://lore.kernel.org/linux-acpi/20191215203303.29811-1-pankaj.bansal@nxp.com/ Signed-off-by: Hanjun Guo Signed-off-by: Lorenzo Pieralisi Cc: Pankaj Bansal Cc: Will Deacon Cc: Sudeep Holla Cc: Catalin Marinas Cc: Robin Murphy Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- drivers/acpi/arm64/iort.c | 57 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 55 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index 5a7551d060f25..161b609e4cdfb 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -298,6 +298,59 @@ out: return status; } +struct iort_workaround_oem_info { + char oem_id[ACPI_OEM_ID_SIZE + 1]; + char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1]; + u32 oem_revision; +}; + +static bool apply_id_count_workaround; + +static struct iort_workaround_oem_info wa_info[] __initdata = { + { + .oem_id = "HISI ", + .oem_table_id = "HIP07 ", + .oem_revision = 0, + }, { + .oem_id = "HISI ", + .oem_table_id = "HIP08 ", + .oem_revision = 0, + } +}; + +static void __init +iort_check_id_count_workaround(struct acpi_table_header *tbl) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(wa_info); i++) { + if (!memcmp(wa_info[i].oem_id, tbl->oem_id, ACPI_OEM_ID_SIZE) && + !memcmp(wa_info[i].oem_table_id, tbl->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) && + wa_info[i].oem_revision == tbl->oem_revision) { + apply_id_count_workaround = true; + pr_warn(FW_BUG "ID count for ID mapping entry is wrong, applying workaround\n"); + break; + } + } +} + +static inline u32 iort_get_map_max(struct acpi_iort_id_mapping *map) +{ + u32 map_max = map->input_base + map->id_count; + + /* + * The IORT specification revision D (Section 3, table 4, page 9) says + * Number of IDs = The number of IDs in the range minus one, but the + * IORT code ignored the "minus one", and some firmware did that too, + * so apply a workaround here to keep compatible with both the spec + * compliant and non-spec compliant firmwares. + */ + if (apply_id_count_workaround) + map_max--; + + return map_max; +} + static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in, u32 *rid_out) { @@ -314,8 +367,7 @@ static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in, return -ENXIO; } - if (rid_in < map->input_base || - (rid_in >= map->input_base + map->id_count)) + if (rid_in < map->input_base || rid_in > iort_get_map_max(map)) return -ENXIO; *rid_out = map->output_base + (rid_in - map->input_base); @@ -1637,5 +1689,6 @@ void __init acpi_iort_init(void) return; } + iort_check_id_count_workaround(iort_table); iort_init_platform_devices(); } -- 2.20.1