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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 5DC8BC2B9F4 for ; Mon, 28 Jun 2021 14:38:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 481DB61C75 for ; Mon, 28 Jun 2021 14:38:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233538AbhF1OlF (ORCPT ); Mon, 28 Jun 2021 10:41:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:43904 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234872AbhF1Oiq (ORCPT ); Mon, 28 Jun 2021 10:38:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 61E7F61CBC; Mon, 28 Jun 2021 14:31:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1624890669; bh=KtcymRdT+1CBlwyLc61Jqq26B+Th16uSrYJNu5eTvKE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=T/dY3bzaTtd/WSzkMTmNeKpF+tenpWd9hXzfC+eBQkOMAaQZ00MW5wnN6ugjdhQqU c5NhI6Oq+ug5MC5WjK4yQ6In3KkGYuCe6zooI+iIGpD/UOPKq+0iyDgS3yqHhz4aw5 jlnXEM6Um8XOQa9nAKHvPTbWKbyq40JhJXDzjjh7MQ8vcPviRURgmAUP3E7MA/Fc/l eUDRY5urTxI/6n7AMj+NkUwkaoMRYc2Tv9P5bT/mIHziwQ/l60xIM99ijsYw+WmowW qt3oJWw8C1e+rOqvJvc9XLlRx27QQMSLU0zV3m8MdbjsvXXhbFwKhUAJhPWaj0ZIBa PMwksRGdIbJGA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: 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 , Greg Kroah-Hartman Subject: [PATCH 5.4 58/71] mm: page_vma_mapped_walk(): use pmde for *pvmw->pmd Date: Mon, 28 Jun 2021 10:29:51 -0400 Message-Id: <20210628143004.32596-59-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210628143004.32596-1-sashal@kernel.org> References: <20210628143004.32596-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.4.129-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-5.4.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 5.4.129-rc1 X-KernelTest-Deadline: 2021-06-30T14:29+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Hugh Dickins 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: Greg Kroah-Hartman --- 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 ebf021d4e68b..76503169c1e2 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