From patchwork Wed Jan 4 18:30:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pierre Gondois X-Patchwork-Id: 639085 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 77CBFC54EBF for ; Wed, 4 Jan 2023 18:32:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239524AbjADScP (ORCPT ); Wed, 4 Jan 2023 13:32:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41772 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239814AbjADSbj (ORCPT ); Wed, 4 Jan 2023 13:31:39 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 276CADEA2; Wed, 4 Jan 2023 10:31:38 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A5FD41063; Wed, 4 Jan 2023 10:32:19 -0800 (PST) Received: from pierre123.arm.com (unknown [10.57.44.105]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 071103F663; Wed, 4 Jan 2023 10:31:33 -0800 (PST) From: Pierre Gondois To: linux-kernel@vger.kernel.org Cc: Pierre Gondois , Krzysztof Kozlowski , Catalin Marinas , Will Deacon , Paul Walmsley , Palmer Dabbelt , Albert Ou , "Rafael J. Wysocki" , Len Brown , Sudeep Holla , Greg Kroah-Hartman , Jeremy Linton , Conor Dooley , Gavin Shan , linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, linux-acpi@vger.kernel.org Subject: [PATCH v4 3/6] cacheinfo: Check 'cache-unified' property to count cache leaves Date: Wed, 4 Jan 2023 19:30:26 +0100 Message-Id: <20230104183033.755668-4-pierre.gondois@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230104183033.755668-1-pierre.gondois@arm.com> References: <20230104183033.755668-1-pierre.gondois@arm.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org The DeviceTree Specification v0.3 specifies that the cache node '[d-|i-|]cache-size' property is required. The 'cache-unified' property is specifies whether the cache level is separate or unified. If the cache-size property is missing, no cache leaves is accounted. This can lead to a 'BUG: KASAN: slab-out-of-bounds' [1] bug. Check 'cache-unified' property and always account for at least one cache leave when parsing the device tree. [1] https://lore.kernel.org/all/0f19cb3f-d6cf-4032-66d2-dedc9d09a0e3@linaro.org/ Reported-by: Krzysztof Kozlowski Signed-off-by: Pierre Gondois Tested-by: Krzysztof Kozlowski --- drivers/base/cacheinfo.c | 37 ++++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 11 deletions(-) diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index 3e965ef6ee42..339cd1e3d5af 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -225,12 +225,9 @@ static int cache_setup_of_node(unsigned int cpu) return 0; } -int init_of_cache_level(unsigned int cpu) +static int of_count_cache_leaves(struct device_node *np) { - struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); - struct device_node *np = of_cpu_device_node_get(cpu); - struct device_node *prev = NULL; - unsigned int levels = 0, leaves = 0, level; + unsigned int leaves = 0; if (of_property_read_bool(np, "cache-size")) ++leaves; @@ -238,6 +235,28 @@ int init_of_cache_level(unsigned int cpu) ++leaves; if (of_property_read_bool(np, "d-cache-size")) ++leaves; + + if (!leaves) { + /* The '[i-|d-|]cache-size' property is required, but + * if absent, fallback on the 'cache-unified' property. + */ + if (of_property_read_bool(np, "cache-unified")) + return 1; + else + return 2; + } + + return leaves; +} + +int init_of_cache_level(unsigned int cpu) +{ + struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); + struct device_node *np = of_cpu_device_node_get(cpu); + struct device_node *prev = NULL; + unsigned int levels = 0, leaves, level; + + leaves = of_count_cache_leaves(np); if (leaves > 0) levels = 1; @@ -251,12 +270,8 @@ int init_of_cache_level(unsigned int cpu) goto err_out; if (level <= levels) goto err_out; - if (of_property_read_bool(np, "cache-size")) - ++leaves; - if (of_property_read_bool(np, "i-cache-size")) - ++leaves; - if (of_property_read_bool(np, "d-cache-size")) - ++leaves; + + leaves += of_count_cache_leaves(np); levels = level; }