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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D397C433F5 for ; Wed, 13 Apr 2022 08:16:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EF7ED6B0072; Wed, 13 Apr 2022 04:16:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id EA7DF6B0073; Wed, 13 Apr 2022 04:16:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D6EEF6B0074; Wed, 13 Apr 2022 04:16:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.27]) by kanga.kvack.org (Postfix) with ESMTP id C7BEF6B0072 for ; Wed, 13 Apr 2022 04:16:18 -0400 (EDT) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 83F2421395 for ; Wed, 13 Apr 2022 08:16:18 +0000 (UTC) X-FDA: 79351148436.07.CB99211 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by imf20.hostedemail.com (Postfix) with ESMTP id 3A64B1C0002 for ; Wed, 13 Apr 2022 08:16:17 +0000 (UTC) Received: from kwepemi100016.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4Kdb3N0pDTzgYh8; Wed, 13 Apr 2022 16:14:24 +0800 (CST) Received: from kwepemm600017.china.huawei.com (7.193.23.234) by kwepemi100016.china.huawei.com (7.221.188.123) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 13 Apr 2022 16:16:13 +0800 Received: from [10.174.179.19] (10.174.179.19) by kwepemm600017.china.huawei.com (7.193.23.234) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 13 Apr 2022 16:16:12 +0800 Content-Type: multipart/alternative; boundary="------------3Ds7T2e40E0jcv0HnljOHFtP" Message-ID: <5bbf45e7-1d92-f543-5cfc-bc0141999d46@huawei.com> Date: Wed, 13 Apr 2022 16:16:11 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.3.2 Subject: Re: [PATCH v3 3/4] hugetlb: Fix return value of __setup handlers Content-Language: en-US To: Muchun Song CC: , , , , , , , References: <20220413032915.251254-1-liupeng256@huawei.com> <20220413032915.251254-4-liupeng256@huawei.com> From: "liupeng (DM)" In-Reply-To: X-Originating-IP: [10.174.179.19] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To kwepemm600017.china.huawei.com (7.193.23.234) X-CFilter-Loop: Reflected X-Stat-Signature: fux765gdcopif9dq6esizi8hgrbtgowh X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 3A64B1C0002 Authentication-Results: imf20.hostedemail.com; dkim=none; spf=pass (imf20.hostedemail.com: domain of liupeng256@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=liupeng256@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com X-Rspam-User: X-HE-Tag: 1649837777-647765 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: --------------3Ds7T2e40E0jcv0HnljOHFtP Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit On 2022/4/13 15:55, Muchun Song wrote: > On Wed, Apr 13, 2022 at 03:29:14AM +0000, Peng Liu wrote: >> When __setup() return '0', using invalid option values causes the >> entire kernel boot option string to be reported as Unknown. Hugetlb >> calls __setup() and will return '0' when set invalid parameter >> string. >> >> The following phenomenon is observed: >> cmdline: >> hugepagesz=1Y hugepages=1 >> dmesg: >> HugeTLB: unsupported hugepagesz=1Y >> HugeTLB: hugepages=1 does not follow a valid hugepagesz, ignoring >> Unknown kernel command line parameters "hugepagesz=1Y hugepages=1" >> >> Since hugetlb will print warning/error information before return for >> invalid parameter string, just use return '1' to avoid print again. >> > Can't return -EINVAL? It is weird to return 1 on failure. > > Thanks. > > . Not against "return -EINVAL", but consistent with: 1d02b444b8d1 ("tracing: Fix return value of __setup handlers") --------------3Ds7T2e40E0jcv0HnljOHFtP Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: 7bit


On 2022/4/13 15:55, Muchun Song wrote:
On Wed, Apr 13, 2022 at 03:29:14AM +0000, Peng Liu wrote:

When __setup() return '0', using invalid option values causes the
entire kernel boot option string to be reported as Unknown. Hugetlb
calls __setup() and will return '0' when set invalid parameter
string.

The following phenomenon is observed:
 cmdline:
  hugepagesz=1Y hugepages=1
 dmesg:
  HugeTLB: unsupported hugepagesz=1Y
  HugeTLB: hugepages=1 does not follow a valid hugepagesz, ignoring
  Unknown kernel command line parameters "hugepagesz=1Y hugepages=1"

Since hugetlb will print warning/error information before return for
invalid parameter string, just use return '1' to avoid print again.


Can't return -EINVAL? It is weird to return 1 on failure.

Thanks.

.
Not against "return -EINVAL", but consistent with:
1d02b444b8d1 ("tracing: Fix return value of __setup handlers")


    

  

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