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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 774ADC433EF for ; Tue, 28 Sep 2021 08:34:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 50DDF611BD for ; Tue, 28 Sep 2021 08:34:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239616AbhI1Ifz (ORCPT ); Tue, 28 Sep 2021 04:35:55 -0400 Received: from szxga02-in.huawei.com ([45.249.212.188]:13362 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235918AbhI1Ify (ORCPT ); Tue, 28 Sep 2021 04:35:54 -0400 Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4HJXjq4wpPz8ynb; Tue, 28 Sep 2021 16:29:35 +0800 (CST) Received: from kwepemm600016.china.huawei.com (7.193.23.20) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Tue, 28 Sep 2021 16:34:13 +0800 Received: from [10.67.102.67] (10.67.102.67) by kwepemm600016.china.huawei.com (7.193.23.20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Tue, 28 Sep 2021 16:34:12 +0800 Subject: Re: [PATCH] net: hns3: fix hclge_dbg_dump_tm_pg() stack usage To: Arnd Bergmann , Yisen Zhuang , Salil Mehta , "David S. Miller" , Jakub Kicinski CC: Arnd Bergmann , Huazhong Tan , Yufeng Mo , Jiaran Zhang , "Jian Shen" , , References: <20210927095006.868305-1-arnd@kernel.org> From: "huangguangbin (A)" Message-ID: Date: Tue, 28 Sep 2021 16:34:11 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: <20210927095006.868305-1-arnd@kernel.org> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.102.67] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To kwepemm600016.china.huawei.com (7.193.23.20) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021/9/27 17:49, Arnd Bergmann wrote: > From: Arnd Bergmann > > This function copies strings around between multiple buffers > including a large on-stack array that causes a build warning > on 32-bit systems: > > drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c: In function 'hclge_dbg_dump_tm_pg': > drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c:782:1: error: the frame size of 1424 bytes is larger than 1400 bytes [-Werror=frame-larger-than=] > > The function can probably be cleaned up a lot, to go back to > printing directly into the output buffer, but dynamically allocating > the structure is a simpler workaround for now. > > Fixes: 04d96139ddb3 ("net: hns3: refine function hclge_dbg_dump_tm_pri()") > Signed-off-by: Arnd Bergmann > --- > .../hisilicon/hns3/hns3pf/hclge_debugfs.c | 26 ++++++++++++++++--- > 1 file changed, 22 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c > index 87d96f82c318..3ed87814100a 100644 > --- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c > +++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c > @@ -719,9 +719,9 @@ static void hclge_dbg_fill_shaper_content(struct hclge_tm_shaper_para *para, > sprintf(result[(*index)++], "%6u", para->rate); > } > > -static int hclge_dbg_dump_tm_pg(struct hclge_dev *hdev, char *buf, int len) > +static int __hclge_dbg_dump_tm_pg(struct hclge_dev *hdev, char *data_str, > + char *buf, int len) > { > - char data_str[ARRAY_SIZE(tm_pg_items)][HCLGE_DBG_DATA_STR_LEN]; > struct hclge_tm_shaper_para c_shaper_para, p_shaper_para; > char *result[ARRAY_SIZE(tm_pg_items)], *sch_mode_str; > u8 pg_id, sch_mode, weight, pri_bit_map, i, j; > @@ -729,8 +729,10 @@ static int hclge_dbg_dump_tm_pg(struct hclge_dev *hdev, char *buf, int len) > int pos = 0; > int ret; > > - for (i = 0; i < ARRAY_SIZE(tm_pg_items); i++) > - result[i] = &data_str[i][0]; > + for (i = 0; i < ARRAY_SIZE(tm_pg_items); i++) { > + result[i] = data_str; > + data_str += HCLGE_DBG_DATA_STR_LEN; > + } > > hclge_dbg_fill_content(content, sizeof(content), tm_pg_items, > NULL, ARRAY_SIZE(tm_pg_items)); > @@ -781,6 +783,22 @@ static int hclge_dbg_dump_tm_pg(struct hclge_dev *hdev, char *buf, int len) > return 0; > } > > +static int hclge_dbg_dump_tm_pg(struct hclge_dev *hdev, char *buf, int len) > +{ > + int ret; > + char *data_str = kcalloc(ARRAY_SIZE(tm_pg_items), > + HCLGE_DBG_DATA_STR_LEN, GFP_KERNEL); > + Hi Arnd, thanks your modification, according to linux code style, should the code be written as follow? char *data_str; int ret; data_str = kcalloc(ARRAY_SIZE(tm_pg_items), HCLGE_DBG_DATA_STR_LEN, GFP_KERNEL); > + if (!data_str) > + return -ENOMEM; > + > + ret = __hclge_dbg_dump_tm_pg(hdev, data_str, buf, len); > + > + kfree(data_str); > + > + return ret; > +} > + > static int hclge_dbg_dump_tm_port(struct hclge_dev *hdev, char *buf, int len) > { > struct hclge_tm_shaper_para shaper_para; >