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 0E069C6FA83 for ; Tue, 13 Sep 2022 09:06:20 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 821FF8D0001; Tue, 13 Sep 2022 05:06:20 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7D14F6B0073; Tue, 13 Sep 2022 05:06:20 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6C0658D0001; Tue, 13 Sep 2022 05:06:20 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 5D97F6B0072 for ; Tue, 13 Sep 2022 05:06:20 -0400 (EDT) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 2C9691A0FDA for ; Tue, 13 Sep 2022 09:06:20 +0000 (UTC) X-FDA: 79906480920.05.56569E5 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf29.hostedemail.com (Postfix) with ESMTP id 7ABD91200DA for ; Tue, 13 Sep 2022 09:06:19 +0000 (UTC) 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 1E1D01063; Tue, 13 Sep 2022 02:06:25 -0700 (PDT) Received: from [10.162.42.9] (unknown [10.162.42.9]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 57AFB3F73B; Tue, 13 Sep 2022 02:06:16 -0700 (PDT) Message-ID: <976e07e6-cfef-da8b-1a08-bab4601fa433@arm.com> Date: Tue, 13 Sep 2022 14:36:13 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH 13/16] mm/page_alloc: init local variable buddy_pfn Content-Language: en-US To: Miaohe Lin , akpm@linux-foundation.org Cc: david@redhat.com, osalvador@suse.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20220909092451.24883-1-linmiaohe@huawei.com> <20220909092451.24883-14-linmiaohe@huawei.com> From: Anshuman Khandual In-Reply-To: <20220909092451.24883-14-linmiaohe@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1663059979; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ja3u+bLHOS3FpPFhV9WxSa9TzugOg5/AoXK7XHGfugM=; b=VhhRSol9rxzvp4dE+7WMyEsd1L3knHGI38QFHO9FsEIJ2UDxtEeIFDbl7uczgYNBeWNPoc 5I15DMejlpoS2IlaNp6YEts3zNVNlv6vyY2/O00Qbg0M4dYtBeXBk1D8Qba+XdJzlRqnT+ D6QyF+pel+yaEnsyHMio/imkFRzMju8= ARC-Authentication-Results: i=1; imf29.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf29.hostedemail.com: domain of anshuman.khandual@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=anshuman.khandual@arm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1663059979; a=rsa-sha256; cv=none; b=jVpYi5jnMVQrVFn0PiEh7DsMmxVOXmxWUZKxfd/5GdowYswwD68R5jg4wktKZZTh2fbYFy MS9vdtWlwBeq78MJPSQ5iqPZU/k+cV7vskhRX8DkpeksjozFkkSg0xOf7KDcfmkc5O4mgm xe3hqUnEJQ7H5CjoZPhMjhdWUBTQyn8= X-Rspamd-Queue-Id: 7ABD91200DA X-Rspam-User: Authentication-Results: imf29.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf29.hostedemail.com: domain of anshuman.khandual@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=anshuman.khandual@arm.com X-Rspamd-Server: rspam02 X-Stat-Signature: rie9icxcknxjggtkhit1t81b65a7i3tx X-HE-Tag: 1663059979-350939 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: On 9/9/22 14:54, Miaohe Lin wrote: > The local variable buddy_pfn could be passed to buddy_merge_likely() > without initialization if the passed in order is MAX_ORDER - 1. This > looks buggy but buddy_pfn won't be used in this case as there's a > order >= MAX_ORDER - 2 check. Init buddy_pfn to 0 anyway to avoid > possible future misuse. > > Signed-off-by: Miaohe Lin Reviewed-by: Anshuman Khandual > --- > mm/page_alloc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index e1c7f98cff96..63ad25e86010 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1113,7 +1113,7 @@ static inline void __free_one_page(struct page *page, > int migratetype, fpi_t fpi_flags) > { > struct capture_control *capc = task_capc(zone); > - unsigned long buddy_pfn; > + unsigned long buddy_pfn = 0; > unsigned long combined_pfn; > struct page *buddy; > bool to_tail;