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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 55BDAC432BE for ; Mon, 30 Aug 2021 14:10:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2EF3460F45 for ; Mon, 30 Aug 2021 14:10:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237086AbhH3OLe (ORCPT ); Mon, 30 Aug 2021 10:11:34 -0400 Received: from szxga03-in.huawei.com ([45.249.212.189]:15273 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237010AbhH3OLU (ORCPT ); Mon, 30 Aug 2021 10:11:20 -0400 Received: from dggeme703-chm.china.huawei.com (unknown [172.30.72.56]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4Gysf32rb7z88XN; Mon, 30 Aug 2021 22:10:03 +0800 (CST) Received: from huawei.com (10.175.124.27) by dggeme703-chm.china.huawei.com (10.1.199.99) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.8; Mon, 30 Aug 2021 22:10:23 +0800 From: Miaohe Lin To: CC: , , , , , , Subject: [PATCH 5/6] mm/page_alloc.c: avoid accessing uninitialized pcp page migratetype Date: Mon, 30 Aug 2021 22:10:50 +0800 Message-ID: <20210830141051.64090-6-linmiaohe@huawei.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20210830141051.64090-1-linmiaohe@huawei.com> References: <20210830141051.64090-1-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: dggems703-chm.china.huawei.com (10.3.19.180) To dggeme703-chm.china.huawei.com (10.1.199.99) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If it's not prepared to free unref page, the pcp page migratetype is unset. Thus We will get rubbish from get_pcppage_migratetype() and might list_del &page->lru again after it's already deleted from the list leading to grumble about data corruption. Fixes: 3dcbe270d8ec ("mm/page_alloc: avoid conflating IRQs disabled with zone->lock") Signed-off-by: Miaohe Lin --- mm/page_alloc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 7bb79e959ab4..d87b7e6e9e6b 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3415,8 +3415,10 @@ void free_unref_page_list(struct list_head *list) /* Prepare pages for freeing */ list_for_each_entry_safe(page, next, list, lru) { pfn = page_to_pfn(page); - if (!free_unref_page_prepare(page, pfn, 0)) + if (!free_unref_page_prepare(page, pfn, 0)) { list_del(&page->lru); + continue; + } /* * Free isolated pages directly to the allocator, see -- 2.23.0