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,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 43936CA9ED0 for ; Fri, 18 Oct 2019 04:55:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 16FD8222C3 for ; Fri, 18 Oct 2019 04:55:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="WlTqEoi5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2409223AbfJREzr (ORCPT ); Fri, 18 Oct 2019 00:55:47 -0400 Received: from hqemgate14.nvidia.com ([216.228.121.143]:2690 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392808AbfJREzq (ORCPT ); Fri, 18 Oct 2019 00:55:46 -0400 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate14.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Thu, 17 Oct 2019 21:55:50 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Thu, 17 Oct 2019 21:55:45 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Thu, 17 Oct 2019 21:55:45 -0700 Received: from HQMAIL101.nvidia.com (172.20.187.10) by HQMAIL105.nvidia.com (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Fri, 18 Oct 2019 04:55:45 +0000 Received: from hqnvemgw03.nvidia.com (10.124.88.68) by HQMAIL101.nvidia.com (172.20.187.10) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Fri, 18 Oct 2019 04:55:45 +0000 Received: from blueforge.nvidia.com (Not Verified[10.110.48.28]) by hqnvemgw03.nvidia.com with Trustwave SEG (v7,5,8,10121) id ; Thu, 17 Oct 2019 21:55:45 -0700 From: John Hubbard To: Viresh Kumar , Shilpasri G Bhat CC: LKML , John Hubbard , Preeti U Murthy , "Rafael J . Wysocki" , , Subject: [PATCH v2] cpufreq: powernv: fix stack bloat and NR_CPUS limitation Date: Thu, 17 Oct 2019 21:55:39 -0700 Message-ID: <20191018045539.3765565-1-jhubbard@nvidia.com> X-Mailer: git-send-email 2.23.0 MIME-Version: 1.0 X-NVConfidentiality: public Content-Transfer-Encoding: quoted-printable Content-Type: text/plain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1571374550; bh=df18Gs5j3cwrHl5PwObGl2FSzw7tZwBe+5B9upV/qmU=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: MIME-Version:X-NVConfidentiality:Content-Transfer-Encoding: Content-Type; b=WlTqEoi5Gs0evA3sLhhGZhfcxwx3m/vSQElv4bqkxcVwKpJJr19qDRntWBEMKxukr pvDQ8O0f8J0Y0ueNopFf/SiMkUxcKJWUMbyucxzHNsumK+iBvAMwN6k1LFlyMgKhuK QMB93N+E2Rz3FittCdYokclkYTAA7YRoW0o6AkQhwCI8n6HZADPwqGZSl55kv/oQN7 /7avi+Xqhrt8s/39ZIs70NEca9ePo3eccO4OhblbWS3XWTaSNG6KO1GAZa0A52UTRO hU0PkUcGepqdlRb1NlIKtyGwVnfJiWQWKNqFRQBisPvefqIsZNaxio6Y6pAl9kPvTf /92RK4C9M0l3Q== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following build warning occurred on powerpc 64-bit builds: drivers/cpufreq/powernv-cpufreq.c: In function 'init_chip_info': drivers/cpufreq/powernv-cpufreq.c:1070:1: warning: the frame size of 1040 b= ytes is larger than 1024 bytes [-Wframe-larger-than=3D] This is due to putting 1024 bytes on the stack: unsigned int chip[256]; ...and while looking at this, it also has a bug: it fails with a stack overrun, if CONFIG_NR_CPUS > 256. Fix both problems by dynamically allocating based on CONFIG_NR_CPUS. Fixes: 053819e0bf840 ("cpufreq: powernv: Handle throttling due to Pmax capp= ing at chip level") Cc: Shilpasri G Bhat Cc: Preeti U Murthy Cc: Viresh Kumar Cc: Rafael J. Wysocki Cc: linux-pm@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: John Hubbard --- Changes since v1: includes Viresh's review commit fixes. drivers/cpufreq/powernv-cpufreq.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cp= ufreq.c index 6061850e59c9..5b2e968cb5ea 100644 --- a/drivers/cpufreq/powernv-cpufreq.c +++ b/drivers/cpufreq/powernv-cpufreq.c @@ -1041,9 +1041,14 @@ static struct cpufreq_driver powernv_cpufreq_driver = =3D { =20 static int init_chip_info(void) { - unsigned int chip[256]; + unsigned int *chip; unsigned int cpu, i; unsigned int prev_chip_id =3D UINT_MAX; + int ret =3D 0; + + chip =3D kcalloc(CONFIG_NR_CPUS, sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; =20 for_each_possible_cpu(cpu) { unsigned int id =3D cpu_to_chip_id(cpu); @@ -1055,8 +1060,10 @@ static int init_chip_info(void) } =20 chips =3D kcalloc(nr_chips, sizeof(struct chip), GFP_KERNEL); - if (!chips) - return -ENOMEM; + if (!chips) { + ret =3D -ENOMEM; + goto free_and_return; + } =20 for (i =3D 0; i < nr_chips; i++) { chips[i].id =3D chip[i]; @@ -1066,7 +1073,9 @@ static int init_chip_info(void) per_cpu(chip_info, cpu) =3D &chips[i]; } =20 - return 0; +free_and_return: + kfree(chip); + return ret; } =20 static inline void clean_chip_info(void) --=20 2.23.0 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=-9.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 8EC32CA9ED0 for ; Fri, 18 Oct 2019 04:58:13 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3A98E222C5 for ; 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Fri, 18 Oct 2019 04:55:45 +0000 Received: from blueforge.nvidia.com (Not Verified[10.110.48.28]) by hqnvemgw03.nvidia.com with Trustwave SEG (v7, 5, 8, 10121) id ; Thu, 17 Oct 2019 21:55:45 -0700 From: John Hubbard To: Viresh Kumar , Shilpasri G Bhat Subject: [PATCH v2] cpufreq: powernv: fix stack bloat and NR_CPUS limitation Date: Thu, 17 Oct 2019 21:55:39 -0700 Message-ID: <20191018045539.3765565-1-jhubbard@nvidia.com> X-Mailer: git-send-email 2.23.0 MIME-Version: 1.0 X-NVConfidentiality: public Content-Transfer-Encoding: quoted-printable Content-Type: text/plain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1571374550; bh=df18Gs5j3cwrHl5PwObGl2FSzw7tZwBe+5B9upV/qmU=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: MIME-Version:X-NVConfidentiality:Content-Transfer-Encoding: Content-Type; b=WlTqEoi5Gs0evA3sLhhGZhfcxwx3m/vSQElv4bqkxcVwKpJJr19qDRntWBEMKxukr pvDQ8O0f8J0Y0ueNopFf/SiMkUxcKJWUMbyucxzHNsumK+iBvAMwN6k1LFlyMgKhuK QMB93N+E2Rz3FittCdYokclkYTAA7YRoW0o6AkQhwCI8n6HZADPwqGZSl55kv/oQN7 /7avi+Xqhrt8s/39ZIs70NEca9ePo3eccO4OhblbWS3XWTaSNG6KO1GAZa0A52UTRO hU0PkUcGepqdlRb1NlIKtyGwVnfJiWQWKNqFRQBisPvefqIsZNaxio6Y6pAl9kPvTf /92RK4C9M0l3Q== X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pm@vger.kernel.org, John Hubbard , "Rafael J . Wysocki" , LKML , Preeti U Murthy , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" The following build warning occurred on powerpc 64-bit builds: drivers/cpufreq/powernv-cpufreq.c: In function 'init_chip_info': drivers/cpufreq/powernv-cpufreq.c:1070:1: warning: the frame size of 1040 b= ytes is larger than 1024 bytes [-Wframe-larger-than=3D] This is due to putting 1024 bytes on the stack: unsigned int chip[256]; ...and while looking at this, it also has a bug: it fails with a stack overrun, if CONFIG_NR_CPUS > 256. Fix both problems by dynamically allocating based on CONFIG_NR_CPUS. Fixes: 053819e0bf840 ("cpufreq: powernv: Handle throttling due to Pmax capp= ing at chip level") Cc: Shilpasri G Bhat Cc: Preeti U Murthy Cc: Viresh Kumar Cc: Rafael J. Wysocki Cc: linux-pm@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: John Hubbard --- Changes since v1: includes Viresh's review commit fixes. drivers/cpufreq/powernv-cpufreq.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cp= ufreq.c index 6061850e59c9..5b2e968cb5ea 100644 --- a/drivers/cpufreq/powernv-cpufreq.c +++ b/drivers/cpufreq/powernv-cpufreq.c @@ -1041,9 +1041,14 @@ static struct cpufreq_driver powernv_cpufreq_driver = =3D { =20 static int init_chip_info(void) { - unsigned int chip[256]; + unsigned int *chip; unsigned int cpu, i; unsigned int prev_chip_id =3D UINT_MAX; + int ret =3D 0; + + chip =3D kcalloc(CONFIG_NR_CPUS, sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; =20 for_each_possible_cpu(cpu) { unsigned int id =3D cpu_to_chip_id(cpu); @@ -1055,8 +1060,10 @@ static int init_chip_info(void) } =20 chips =3D kcalloc(nr_chips, sizeof(struct chip), GFP_KERNEL); - if (!chips) - return -ENOMEM; + if (!chips) { + ret =3D -ENOMEM; + goto free_and_return; + } =20 for (i =3D 0; i < nr_chips; i++) { chips[i].id =3D chip[i]; @@ -1066,7 +1073,9 @@ static int init_chip_info(void) per_cpu(chip_info, cpu) =3D &chips[i]; } =20 - return 0; +free_and_return: + kfree(chip); + return ret; } =20 static inline void clean_chip_info(void) --=20 2.23.0