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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 54F45C388F7 for ; Sat, 7 Nov 2020 15:39:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 19DE72087E for ; Sat, 7 Nov 2020 15:39:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604763573; bh=LWT7Qaq/B7VN8y1nITNGgWXYNxgiKYc81vOZ691JfkI=; h=Subject:To:Cc:From:Date:List-ID:From; b=PQSFYcfgE9zQX09GBWk85MSpGnJF1s92mYuyotUTtOV9bcMrf9zwl2UuGuAE7Nr/0 9tYyI91GmFe/ha7yUApcHv4+T4iYtkfKA08CWx2Wzgg0EmKyskdZOz65WV8pw//jZX dI17wcLlWISCou7vLj2HQwZXrRBtBnb1lnk1YTKw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728232AbgKGPjc (ORCPT ); Sat, 7 Nov 2020 10:39:32 -0500 Received: from wforward1-smtp.messagingengine.com ([64.147.123.30]:52601 "EHLO wforward1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728177AbgKGPj2 (ORCPT ); Sat, 7 Nov 2020 10:39:28 -0500 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailforward.west.internal (Postfix) with ESMTP id 529F5F7B; Sat, 7 Nov 2020 10:39:27 -0500 (EST) Received: from mailfrontend1 ([10.202.2.162]) by compute4.internal (MEProxy); Sat, 07 Nov 2020 10:39:27 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:message-id:mime-version:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm1; bh=vQMNoH /kdcpDAwnAzLSoIA9aWmvJYWwReAZozuQ+Nzg=; b=AZEUwzJbQ0LlUCIDOQbpMD jJ8Qhl5E1ZpJscxBF6rSOhAldQar5N5L4Baf9cM64EN5T3maN1a4lC/SDNc30MPN a7jmZV14epVUd68vM9i5kMGCDojSrudQ3Izmcq19JzYrQ2qgFhVwfhV6ZteHFciS VVHjBQi3NPEDqXAFh79YExBiaxaHW5+07iCXiOKHL8E6yljrj0nr71y0ObYYcBnh jb13yYuIsW0RTRnwBCfSNm2Gd5YM6AwLoSvY9ZwR3RxEFwrDZATofJCguF/JimvE c7bLLDAgPqEGR/KVRLLekaltYWFTb2RAA4q87IGmTCtP4YPTfauSmKJMa7iedUoQ == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedujedrudduuddgkedtucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucenucfjughrpefuvffhfffkgggtgfesthekredttd dtlfenucfhrhhomhepoehgrhgvghhkhheslhhinhhugihfohhunhgurghtihhonhdrohhr gheqnecuggftrfgrthhtvghrnhepleelledvgeefleeltdetgedugeffgffhudffudduke egfeelgeeigeekjefhleevnecuffhomhgrihhnpehkvghrnhgvlhdrohhrghenucfkphep keefrdekiedrjeegrdeigeenucevlhhushhtvghrufhiiigvpedunecurfgrrhgrmhepmh grihhlfhhrohhmpehgrhgvgheskhhrohgrhhdrtghomh X-ME-Proxy: Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) by mail.messagingengine.com (Postfix) with ESMTPA id 79BC532803D4; Sat, 7 Nov 2020 10:39:26 -0500 (EST) Subject: FAILED: patch "[PATCH] mm: mempolicy: fix potential pte_unmap_unlock pte error" failed to apply to 4.9-stable tree To: luoshijie1@huawei.com, akpm@linux-foundation.org, linfeilong@huawei.com, linmiaohe@huawei.com, mhocko@suse.com, osalvador@suse.de, stable@vger.kernel.org, torvalds@linux-foundation.org Cc: From: Date: Sat, 07 Nov 2020 16:40:03 +0100 Message-ID: <160476360386106@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 3f08842098e842c51e3b97d0dcdebf810b32558e Mon Sep 17 00:00:00 2001 From: Shijie Luo Date: Sun, 1 Nov 2020 17:07:40 -0800 Subject: [PATCH] mm: mempolicy: fix potential pte_unmap_unlock pte error When flags in queue_pages_pte_range don't have MPOL_MF_MOVE or MPOL_MF_MOVE_ALL bits, code breaks and passing origin pte - 1 to pte_unmap_unlock seems like not a good idea. queue_pages_pte_range can run in MPOL_MF_MOVE_ALL mode which doesn't migrate misplaced pages but returns with EIO when encountering such a page. Since commit a7f40cfe3b7a ("mm: mempolicy: make mbind() return -EIO when MPOL_MF_STRICT is specified") and early break on the first pte in the range results in pte_unmap_unlock on an underflow pte. This can lead to lockups later on when somebody tries to lock the pte resp. page_table_lock again.. Fixes: a7f40cfe3b7a ("mm: mempolicy: make mbind() return -EIO when MPOL_MF_STRICT is specified") Signed-off-by: Shijie Luo Signed-off-by: Miaohe Lin Signed-off-by: Andrew Morton Reviewed-by: Oscar Salvador Acked-by: Michal Hocko Cc: Miaohe Lin Cc: Feilong Lin Cc: Shijie Luo Cc: Link: https://lkml.kernel.org/r/20201019074853.50856-1-luoshijie1@huawei.com Signed-off-by: Linus Torvalds diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 3fde772ef5ef..3ca4898f3f24 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -525,7 +525,7 @@ static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr, unsigned long flags = qp->flags; int ret; bool has_unmovable = false; - pte_t *pte; + pte_t *pte, *mapped_pte; spinlock_t *ptl; ptl = pmd_trans_huge_lock(pmd, vma); @@ -539,7 +539,7 @@ static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr, if (pmd_trans_unstable(pmd)) return 0; - pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); + mapped_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); for (; addr != end; pte++, addr += PAGE_SIZE) { if (!pte_present(*pte)) continue; @@ -571,7 +571,7 @@ static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr, } else break; } - pte_unmap_unlock(pte - 1, ptl); + pte_unmap_unlock(mapped_pte, ptl); cond_resched(); if (has_unmovable)