From patchwork Mon May 22 05:10:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hugh Dickins X-Patchwork-Id: 97024 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp1215295vqo; Sun, 21 May 2023 22:15:58 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ7TRCvTH/4Yz/OW5E5AclML9joIocqCPf8IS367YZk0FHSgfs7qb1SnDzZuEC25xS8ra1GE X-Received: by 2002:aa7:8893:0:b0:643:849a:dd06 with SMTP id z19-20020aa78893000000b00643849add06mr12902048pfe.34.1684732558193; Sun, 21 May 2023 22:15:58 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1684732558; cv=none; d=google.com; s=arc-20160816; b=viPXGytWW+9D4691qBokKuI0KALB26npl7mOn6WqmGql2c04ov98QO1Yks0bHV0KJu DRmr/5ouEU53uhcH4StoShJe6N5mkM9cghDhSSN3dFrrZFJcyVj/Myr41kKKn/RbxWR8 lT7Hp8PavTrBNoHvKohz0+5s+ip2/dbs4dvfPZgACqMwsfYkWeVVsziHAJp/7satGzB8 M1gPETJjO+P83zJkfWxrnjXueOMAwICJY/d08M6jXiprEn7uwAxjZ8/QkINrwy8stzbc 43EP9Qw1e6r4xL1wppW57MRdb/QQ2S3SdeZ4oLEXvoBjmfa1j9tEE5EB8sYcLkkXscwh Dsfg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:references:message-id:in-reply-to :subject:cc:to:from:date:dkim-signature; bh=qkatc+QCc6cccs9xXaqGfaqNL6OFGEuJiK0miGnv7G8=; b=yFxBRrCHV6RhHRvpNagcRSWNUHKgoQZiTnwZtt/y+UO0NqN2BRHgvi/TyqfedSYwRh OwJ/UOfIcpuS2lOgHAzws93pe2wBFQquwAr8ErT7y12C6f7lXyGNTPm6leA4KvGwk0FB kWwglc+GGiU4xBoD06e4PcnUADUdo/Mx8JbeFetFowP5ORxQVpiTetf0akfBK9BpEXXo vwJZCYqJRw+MNcJuGthj7N2S8uMk5n4f/8qNjrb78LZs2EhrBA1UyHwRupD7sJKbgHPR SNEHAWzXFEsQY26ifzCZdKWXNemXfr6gTYENwdKD60TztQO8Dbrg6gYx7KLFi1hBoy2k KUSg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@google.com header.s=20221208 header.b=G8p2CzqF; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id p4-20020a63ab04000000b00535f192eac7si268852pgf.211.2023.05.21.22.15.45; Sun, 21 May 2023 22:15:58 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20221208 header.b=G8p2CzqF; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231950AbjEVFKv (ORCPT + 99 others); Mon, 22 May 2023 01:10:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51950 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231804AbjEVFKg (ORCPT ); Mon, 22 May 2023 01:10:36 -0400 Received: from mail-yb1-xb36.google.com (mail-yb1-xb36.google.com [IPv6:2607:f8b0:4864:20::b36]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9889D109 for ; Sun, 21 May 2023 22:10:14 -0700 (PDT) Received: by mail-yb1-xb36.google.com with SMTP id 3f1490d57ef6-b9e6ec482b3so8134495276.3 for ; Sun, 21 May 2023 22:10:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1684732209; x=1687324209; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to; bh=qkatc+QCc6cccs9xXaqGfaqNL6OFGEuJiK0miGnv7G8=; b=G8p2CzqFuweOTJakxAlGPjhKL7rDUMtnLNT7EUicI7w+jufYMVBoVuc81ZJQYoSTfb w6t5S+SR5Hp/NszCj/XtFj6CuqMt4ZlVp3PxVkJ3mlWRBt+Iifs7tpZrzkBlF0AC0HZQ qbtqENGFk4bM4644i8k7d4FbjPR3Um0C3R30rKDY1tPszjXHKCLCSRdB9GHFrQ6reUFc o/gs5XQG3ml90zH4fHmJbebDWsSKfY/AnaCH/uwICdx3ExQ+m1F+PTZVZDShUMb4Npmu GRvVy3RMuLlfKPCoJDA4zF1iEeyu+t7qtp3Nzn44IZZdc2OcH7AU7ec8Vtx87ucadbDG 6sAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684732209; x=1687324209; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=qkatc+QCc6cccs9xXaqGfaqNL6OFGEuJiK0miGnv7G8=; b=LVlnEgtWpjBzJAoREowHovZ0aIJp4Du86drlwVFAP9cQNV0pL/EzYtZKe5cs9lMpP7 +K4Loyvr/yjgkGP2PVtJ4XesrCZkPM/OBhgOef9Kc8LSwSytRaHvZBKBo1HGb59LIxYN cfvrn1sq//YJgZl9NEycRzRfFtK+QdAyVgQKVYFhEU9TiwaBxFHPyJ6xsuYvEEsdkTAJ Wk/X2mQl7wmQBb+KoXKa/yllOCM0UUP0WXPB6uGVKgHqgqzlq575x1XLaL7t7KixH039 I1jyESS42tUyEbdilyNTn7ULKkAtvladzXwunG/ghzPukDhREwl3J/aq/I8kQIZ4twb0 fE+g== X-Gm-Message-State: AC+VfDxgfXXadzxpPxSEOd+p7chP8MnIq/wNyoE/W63fshF/zGXNM9yN yhb2hy1Tz6AfHYJgyvzxxP177w== X-Received: by 2002:a0d:d595:0:b0:561:e910:52f5 with SMTP id x143-20020a0dd595000000b00561e91052f5mr12187363ywd.27.1684732208925; Sun, 21 May 2023 22:10:08 -0700 (PDT) Received: from ripple.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id y185-20020a817dc2000000b00545a08184fdsm1790422ywc.141.2023.05.21.22.10.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 21 May 2023 22:10:08 -0700 (PDT) Date: Sun, 21 May 2023 22:10:05 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@ripple.attlocal.net To: Andrew Morton cc: Mike Kravetz , Mike Rapoport , "Kirill A. Shutemov" , Matthew Wilcox , David Hildenbrand , Suren Baghdasaryan , Qi Zheng , Yang Shi , Mel Gorman , Peter Xu , Peter Zijlstra , Will Deacon , Yu Zhao , Alistair Popple , Ralph Campbell , Ira Weiny , Steven Price , SeongJae Park , Naoya Horiguchi , Christophe Leroy , Zack Rusin , Jason Gunthorpe , Axel Rasmussen , Anshuman Khandual , Pasha Tatashin , Miaohe Lin , Minchan Kim , Christoph Hellwig , Song Liu , Thomas Hellstrom , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 17/31] mm/various: give up if pte_offset_map[_lock]() fails In-Reply-To: <68a97fbe-5c1e-7ac6-72c-7b9c6290b370@google.com> Message-ID: References: <68a97fbe-5c1e-7ac6-72c-7b9c6290b370@google.com> MIME-Version: 1.0 X-Spam-Status: No, score=-17.6 required=5.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, ENV_AND_HDR_SPF_MATCH,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE,USER_IN_DEF_DKIM_WL,USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1766570126629690278?= X-GMAIL-MSGID: =?utf-8?q?1766570126629690278?= Following the examples of nearby code, various functions can just give up if pte_offset_map() or pte_offset_map_lock() fails. And there's no need for a preliminary pmd_trans_unstable() or other such check, since such cases are now safely handled inside. Signed-off-by: Hugh Dickins --- mm/gup.c | 9 ++++++--- mm/ksm.c | 7 ++++--- mm/memcontrol.c | 8 ++++---- mm/memory-failure.c | 8 +++++--- mm/migrate.c | 3 +++ mm/swap_state.c | 3 +++ 6 files changed, 25 insertions(+), 13 deletions(-) diff --git a/mm/gup.c b/mm/gup.c index 3bd5d3854c51..bb67193c5460 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -544,10 +544,10 @@ static struct page *follow_page_pte(struct vm_area_struct *vma, if (WARN_ON_ONCE((flags & (FOLL_PIN | FOLL_GET)) == (FOLL_PIN | FOLL_GET))) return ERR_PTR(-EINVAL); - if (unlikely(pmd_bad(*pmd))) - return no_page_table(vma, flags); ptep = pte_offset_map_lock(mm, pmd, address, &ptl); + if (!ptep) + return no_page_table(vma, flags); pte = *ptep; if (!pte_present(pte)) goto no_page; @@ -851,8 +851,9 @@ static int get_gate_page(struct mm_struct *mm, unsigned long address, pmd = pmd_offset(pud, address); if (!pmd_present(*pmd)) return -EFAULT; - VM_BUG_ON(pmd_trans_huge(*pmd)); pte = pte_offset_map(pmd, address); + if (!pte) + return -EFAULT; if (pte_none(*pte)) goto unmap; *vma = get_gate_vma(mm); @@ -2377,6 +2378,8 @@ static int gup_pte_range(pmd_t pmd, pmd_t *pmdp, unsigned long addr, pte_t *ptep, *ptem; ptem = ptep = pte_offset_map(&pmd, addr); + if (!ptep) + return 0; do { pte_t pte = ptep_get_lockless(ptep); struct page *page; diff --git a/mm/ksm.c b/mm/ksm.c index df2aa281d49d..3dc15459dd20 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -431,10 +431,9 @@ static int break_ksm_pmd_entry(pmd_t *pmd, unsigned long addr, unsigned long nex pte_t *pte; int ret; - if (pmd_leaf(*pmd) || !pmd_present(*pmd)) - return 0; - pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); + if (!pte) + return 0; if (pte_present(*pte)) { page = vm_normal_page(walk->vma, addr, *pte); } else if (!pte_none(*pte)) { @@ -1203,6 +1202,8 @@ static int replace_page(struct vm_area_struct *vma, struct page *page, mmu_notifier_invalidate_range_start(&range); ptep = pte_offset_map_lock(mm, pmd, addr, &ptl); + if (!ptep) + goto out_mn; if (!pte_same(*ptep, orig_pte)) { pte_unmap_unlock(ptep, ptl); goto out_mn; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 4b27e245a055..fdd953655fe1 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -6057,9 +6057,9 @@ static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, return 0; } - if (pmd_trans_unstable(pmd)) - return 0; pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); + if (!pte) + return 0; for (; addr != end; pte++, addr += PAGE_SIZE) if (get_mctgt_type(vma, addr, *pte, NULL)) mc.precharge++; /* increment precharge temporarily */ @@ -6277,10 +6277,10 @@ static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, return 0; } - if (pmd_trans_unstable(pmd)) - return 0; retry: pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); + if (!pte) + return 0; for (; addr != end; addr += PAGE_SIZE) { pte_t ptent = *(pte++); bool device = false; diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 5b663eca1f29..b3cc8f213fe3 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -414,6 +414,8 @@ static unsigned long dev_pagemap_mapping_shift(struct vm_area_struct *vma, if (pmd_devmap(*pmd)) return PMD_SHIFT; pte = pte_offset_map(pmd, address); + if (!pte) + return 0; if (pte_present(*pte) && pte_devmap(*pte)) ret = PAGE_SHIFT; pte_unmap(pte); @@ -800,11 +802,11 @@ static int hwpoison_pte_range(pmd_t *pmdp, unsigned long addr, goto out; } - if (pmd_trans_unstable(pmdp)) - goto out; - mapped_pte = ptep = pte_offset_map_lock(walk->vma->vm_mm, pmdp, addr, &ptl); + if (!ptep) + goto out; + for (; addr != end; ptep++, addr += PAGE_SIZE) { ret = check_hwpoisoned_entry(*ptep, addr, PAGE_SHIFT, hwp->pfn, &hwp->tk); diff --git a/mm/migrate.c b/mm/migrate.c index 3ecb7a40075f..308a56f0b156 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -305,6 +305,9 @@ void migration_entry_wait(struct mm_struct *mm, pmd_t *pmd, swp_entry_t entry; ptep = pte_offset_map_lock(mm, pmd, address, &ptl); + if (!ptep) + return; + pte = *ptep; pte_unmap(ptep); diff --git a/mm/swap_state.c b/mm/swap_state.c index b76a65ac28b3..db2ec85ef332 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -734,6 +734,9 @@ static void swap_ra_info(struct vm_fault *vmf, /* Copy the PTEs because the page table may be unmapped */ orig_pte = pte = pte_offset_map(vmf->pmd, faddr); + if (!pte) + return; + if (fpfn == pfn + 1) { lpfn = fpfn; rpfn = fpfn + win;