From nobody Wed Apr 8 07:51:19 2026 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 9803EC28D13 for ; Tue, 23 Aug 2022 03:05:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239839AbiHWDFH (ORCPT ); Mon, 22 Aug 2022 23:05:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54908 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239875AbiHWDEP (ORCPT ); Mon, 22 Aug 2022 23:04:15 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9B1AF5D0ED for ; Mon, 22 Aug 2022 20:02:59 -0700 (PDT) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4MBYr355K3zhYC2; Tue, 23 Aug 2022 11:00:19 +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 15.1.2375.24; Tue, 23 Aug 2022 11:02:37 +0800 From: Miaohe Lin To: , , CC: , , , Subject: [PATCH v2 4/6] mm: hugetlb_vmemmap: add missing smp_wmb() before set_pte_at() Date: Tue, 23 Aug 2022 11:02:07 +0800 Message-ID: <20220823030209.57434-5-linmiaohe@huawei.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20220823030209.57434-1-linmiaohe@huawei.com> References: <20220823030209.57434-1-linmiaohe@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.124.27] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) 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 Content-Type: text/plain; charset="utf-8" The memory barrier smp_wmb() is needed to make sure that preceding stores to the page contents become visible before the below set_pte_at() write. Signed-off-by: Miaohe Lin Reviewed-by: Yin Fengwei Reviewed-by: Muchun Song --- mm/hugetlb_vmemmap.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index 196159000897..ba2a2596fb4e 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -286,6 +286,11 @@ static void vmemmap_restore_pte(pte_t *pte, unsigned l= ong addr, copy_page(to, (void *)walk->reuse_addr); reset_struct_pages(to); =20 + /* + * Makes sure that preceding stores to the page contents become visible + * before the set_pte_at() write. + */ + smp_wmb(); set_pte_at(&init_mm, addr, pte, mk_pte(page, pgprot)); } =20 --=20 2.23.0