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=-19.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 167C3C11F68 for ; Fri, 9 Jul 2021 13:19:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 00B50613C0 for ; Fri, 9 Jul 2021 13:19:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232297AbhGINWX (ORCPT ); Fri, 9 Jul 2021 09:22:23 -0400 Received: from mail.kernel.org ([198.145.29.99]:52860 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232246AbhGINWR (ORCPT ); Fri, 9 Jul 2021 09:22:17 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id DE19C608FE; Fri, 9 Jul 2021 13:19:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1625836770; bh=LTga4WiFdMKiX1kiLBqlUrOP0/NDNahbe58ADmfGgHw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HtWVyvj8gpleRCMIs93y8tU2UajrxZxvQVTGGHrZcFTS2XcmFzTqXhsI3FeGiVeEa liyyvTeuWLOjJhgqf8g23Fzd7HOrp/1JbkQQ6TjxsvyX7o0bGLMon0kzBEXz8tMrfu E86zQmRD7YEfx8koeK4ACDqnrNa2gibxJ0X8MyOM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hugh Dickins , "Kirill A. Shutemov" , Peter Xu , Alistair Popple , Matthew Wilcox , Ralph Campbell , Wang Yugui , Will Deacon , Yang Shi , Zi Yan , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH 4.14 11/25] mm: page_vma_mapped_walk(): use pmde for *pvmw->pmd Date: Fri, 9 Jul 2021 15:18:42 +0200 Message-Id: <20210709131634.530112011@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210709131627.928131764@linuxfoundation.org> References: <20210709131627.928131764@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Hugh Dickins [ Upstream commit 3306d3119ceacc43ea8b141a73e21fea68eec30c ] page_vma_mapped_walk() cleanup: re-evaluate pmde after taking lock, then use it in subsequent tests, instead of repeatedly dereferencing pointer. Link: https://lkml.kernel.org/r/53fbc9d-891e-46b2-cb4b-468c3b19238e@google.com Signed-off-by: Hugh Dickins Acked-by: Kirill A. Shutemov Reviewed-by: Peter Xu Cc: Alistair Popple Cc: Matthew Wilcox Cc: Ralph Campbell Cc: Wang Yugui Cc: Will Deacon Cc: Yang Shi Cc: Zi Yan Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- mm/page_vma_mapped.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index bdb63aafc737..8a6af4007c7e 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -186,18 +186,19 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) pmde = READ_ONCE(*pvmw->pmd); if (pmd_trans_huge(pmde) || is_pmd_migration_entry(pmde)) { pvmw->ptl = pmd_lock(mm, pvmw->pmd); - if (likely(pmd_trans_huge(*pvmw->pmd))) { + pmde = *pvmw->pmd; + if (likely(pmd_trans_huge(pmde))) { if (pvmw->flags & PVMW_MIGRATION) return not_found(pvmw); - if (pmd_page(*pvmw->pmd) != page) + if (pmd_page(pmde) != page) return not_found(pvmw); return true; - } else if (!pmd_present(*pvmw->pmd)) { + } else if (!pmd_present(pmde)) { if (thp_migration_supported()) { if (!(pvmw->flags & PVMW_MIGRATION)) return not_found(pvmw); - if (is_migration_entry(pmd_to_swp_entry(*pvmw->pmd))) { - swp_entry_t entry = pmd_to_swp_entry(*pvmw->pmd); + if (is_migration_entry(pmd_to_swp_entry(pmde))) { + swp_entry_t entry = pmd_to_swp_entry(pmde); if (migration_entry_to_page(entry) != page) return not_found(pvmw); -- 2.30.2