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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C9CACC433EF for ; Fri, 4 Mar 2022 09:36:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239051AbiCDJg6 (ORCPT ); Fri, 4 Mar 2022 04:36:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237452AbiCDJgC (ORCPT ); Fri, 4 Mar 2022 04:36:02 -0500 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 77B1C1903C5 for ; Fri, 4 Mar 2022 01:35:12 -0800 (PST) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4K92jW6Nn2zdgC7; Fri, 4 Mar 2022 17:33:51 +0800 (CST) Received: from huawei.com (10.175.124.27) by canpemm500002.china.huawei.com (7.192.104.244) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Fri, 4 Mar 2022 17:35:09 +0800 From: Miaohe Lin To: CC: , , , , , , , , , , , , , , , , , , Subject: [PATCH 14/16] mm/migration: fix potential invalid node access for reclaim-based migration Date: Fri, 4 Mar 2022 17:34:07 +0800 Message-ID: <20220304093409.25829-15-linmiaohe@huawei.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20220304093409.25829-1-linmiaohe@huawei.com> References: <20220304093409.25829-1-linmiaohe@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.124.27] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If we failed to setup hotplug state callbacks for mm/demotion:online in some corner cases, node_demotion will be left uninitialized. Invalid node might be returned from the next_demotion_node() when doing reclaim-based migration. Use kcalloc to allocate node_demotion to fix the issue. Fixes: ac16ec835314 ("mm: migrate: support multiple target nodes demotion") Signed-off-by: Miaohe Lin --- mm/migrate.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/mm/migrate.c b/mm/migrate.c index 279940c0c064..7b1c0b988234 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2516,9 +2516,9 @@ static int __init migrate_on_reclaim_init(void) { int ret; - node_demotion = kmalloc_array(nr_node_ids, - sizeof(struct demotion_nodes), - GFP_KERNEL); + node_demotion = kcalloc(nr_node_ids, + sizeof(struct demotion_nodes), + GFP_KERNEL); WARN_ON(!node_demotion); ret = cpuhp_setup_state_nocalls(CPUHP_MM_DEMOTION_DEAD, "mm/demotion:offline", -- 2.23.0