From nobody Thu Sep 4 03:33:50 2025 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 D921EC6FA89 for ; Tue, 13 Sep 2022 15:15:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235712AbiIMPPi (ORCPT ); Tue, 13 Sep 2022 11:15:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42638 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235669AbiIMPN2 (ORCPT ); Tue, 13 Sep 2022 11:13:28 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4DA43786D6; Tue, 13 Sep 2022 07:33:05 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A5803614EC; Tue, 13 Sep 2022 14:32:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AF472C433B5; Tue, 13 Sep 2022 14:32:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1663079528; bh=+BWtEheS0cucPhtYcwHqN0Ms/BuehtDS9BrPRX2Kow0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=p/7C/dxmZ7royD5lsyuQ3T6+/Vr3XpyW6X8H+smSkt4q2L4+S4+EnUiKtCN1xbKMW 34AB5QEYkDVOAxx/j+joNWQ5jwXOdEBHkyB0gW3Tulrm88tE43Uwg/878KZYTEgGvI MPtQrNNp82WcJV4dT//MGBIi2ATT3fGu/1GCuNy8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sudeep Holla , Will Deacon , Sasha Levin , Bruno Goncalves Subject: [PATCH 4.19 53/79] arm64: cacheinfo: Fix incorrect assignment of signed error value to unsigned fw_level Date: Tue, 13 Sep 2022 16:07:11 +0200 Message-Id: <20220913140351.469490864@linuxfoundation.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20220913140348.835121645@linuxfoundation.org> References: <20220913140348.835121645@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Sudeep Holla [ Upstream commit e75d18cecbb3805895d8ed64da4f78575ec96043 ] Though acpi_find_last_cache_level() always returned signed value and the document states it will return any errors caused by lack of a PPTT table, it never returned negative values before. Commit 0c80f9e165f8 ("ACPI: PPTT: Leave the table mapped for the runtime us= age") however changed it by returning -ENOENT if no PPTT was found. The value returned from acpi_find_last_cache_level() is then assigned to unsigned fw_level. It will result in the number of cache leaves calculated incorrectly as a huge value which will then cause the following warning from __alloc_pages as the order would be great than MAX_ORDER because of incorrect and huge cache leaves value. | WARNING: CPU: 0 PID: 1 at mm/page_alloc.c:5407 __alloc_pages+0x74/0x314 | Modules linked in: | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.19.0-10393-g7c2a8d3ac4c0 #= 73 | pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=3D--) | pc : __alloc_pages+0x74/0x314 | lr : alloc_pages+0xe8/0x318 | Call trace: | __alloc_pages+0x74/0x314 | alloc_pages+0xe8/0x318 | kmalloc_order_trace+0x68/0x1dc | __kmalloc+0x240/0x338 | detect_cache_attributes+0xe0/0x56c | update_siblings_masks+0x38/0x284 | store_cpu_topology+0x78/0x84 | smp_prepare_cpus+0x48/0x134 | kernel_init_freeable+0xc4/0x14c | kernel_init+0x2c/0x1b4 | ret_from_fork+0x10/0x20 Fix the same by changing fw_level to be signed integer and return the error from init_cache_level() early in case of error. Reported-and-Tested-by: Bruno Goncalves Signed-off-by: Sudeep Holla Link: https://lore.kernel.org/r/20220808084640.3165368-1-sudeep.holla@arm.c= om Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- arch/arm64/kernel/cacheinfo.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kernel/cacheinfo.c b/arch/arm64/kernel/cacheinfo.c index d17414cbb89a8..473935695efb7 100644 --- a/arch/arm64/kernel/cacheinfo.c +++ b/arch/arm64/kernel/cacheinfo.c @@ -47,7 +47,8 @@ static void ci_leaf_init(struct cacheinfo *this_leaf, =20 int init_cache_level(unsigned int cpu) { - unsigned int ctype, level, leaves, fw_level; + unsigned int ctype, level, leaves; + int fw_level; struct cpu_cacheinfo *this_cpu_ci =3D get_cpu_cacheinfo(cpu); =20 for (level =3D 1, leaves =3D 0; level <=3D MAX_CACHE_LEVEL; level++) { @@ -65,6 +66,9 @@ int init_cache_level(unsigned int cpu) else fw_level =3D acpi_find_last_cache_level(cpu); =20 + if (fw_level < 0) + return fw_level; + if (level < fw_level) { /* * some external caches not specified in CLIDR_EL1 --=20 2.35.1