From patchwork Wed Mar 9 09:14:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Naoya Horiguchi X-Patchwork-Id: 12774853 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7398AC4332F for ; Wed, 9 Mar 2022 09:15:13 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D92868D0024; Wed, 9 Mar 2022 04:15:12 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id D42DF8D0001; Wed, 9 Mar 2022 04:15:12 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C58828D0024; Wed, 9 Mar 2022 04:15:12 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.28]) by kanga.kvack.org (Postfix) with ESMTP id B2ADF8D0001 for ; Wed, 9 Mar 2022 04:15:12 -0500 (EST) Received: from smtpin14.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 5F86D24ACA for ; Wed, 9 Mar 2022 09:15:12 +0000 (UTC) X-FDA: 79224288864.14.0E96B21 Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by imf14.hostedemail.com (Postfix) with ESMTP id C4529100015 for ; Wed, 9 Mar 2022 09:15:11 +0000 (UTC) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1646817309; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=olA4r4ZgiOAYFwlfl2Yy38K26xuaM/avMHUMNx9O8Pk=; b=Bp0HuafFKD3+SWGE1W6sp5tYOmKpDRTvBmmbJbFH2VoI5+vvTvUn4qBD3vW6fwAHOp6hze OH+jL3Hl0ab+4sDc+0O6YJyzDe52fZyzlHJ0VWxDnTsmaoEuGrASOlcny2Fogx+psvDrvW DacQxNeNOxNniz57xHkRJepZ7hDkDbA= From: Naoya Horiguchi To: linux-mm@kvack.org Cc: Andrew Morton , Mike Kravetz , Miaohe Lin , Yang Shi , Naoya Horiguchi , linux-kernel@vger.kernel.org Subject: [PATCH v1] mm/hwpoison: set PageHWPoison after taking page lock in memory_failure_hugetlb() Date: Wed, 9 Mar 2022 18:14:49 +0900 Message-Id: <20220309091449.2753904-1-naoya.horiguchi@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev X-Rspamd-Queue-Id: C4529100015 X-Stat-Signature: o8az71oxzz89ex9nsmrrrznm3wejyieb X-Rspam-User: Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=Bp0HuafF; spf=pass (imf14.hostedemail.com: domain of naoya.horiguchi@linux.dev designates 188.165.223.204 as permitted sender) smtp.mailfrom=naoya.horiguchi@linux.dev; dmarc=pass (policy=none) header.from=linux.dev X-Rspamd-Server: rspam07 X-HE-Tag: 1646817311-635218 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Naoya Horiguchi There is a race condition between memory_failure_hugetlb() and hugetlb free/demotion, which causes setting PageHWPoison flag on the wrong page (which was a hugetlb when memory_failrue() was called, but was removed or demoted when memory_failure_hugetlb() is called). This results in killing wrong processes. So set PageHWPoison flag with holding page lock, Signed-off-by: Naoya Horiguchi --- mm/memory-failure.c | 27 ++++++++++++--------------- 1 file changed, 12 insertions(+), 15 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index ac6492e36978..fe25eee8f9d6 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1494,24 +1494,11 @@ static int memory_failure_hugetlb(unsigned long pfn, int flags) int res; unsigned long page_flags; - if (TestSetPageHWPoison(head)) { - pr_err("Memory failure: %#lx: already hardware poisoned\n", - pfn); - res = -EHWPOISON; - if (flags & MF_ACTION_REQUIRED) - res = kill_accessing_process(current, page_to_pfn(head), flags); - return res; - } - - num_poisoned_pages_inc(); - if (!(flags & MF_COUNT_INCREASED)) { res = get_hwpoison_page(p, flags); if (!res) { lock_page(head); if (hwpoison_filter(p)) { - if (TestClearPageHWPoison(head)) - num_poisoned_pages_dec(); unlock_page(head); return -EOPNOTSUPP; } @@ -1544,13 +1531,16 @@ static int memory_failure_hugetlb(unsigned long pfn, int flags) page_flags = head->flags; if (hwpoison_filter(p)) { - if (TestClearPageHWPoison(head)) - num_poisoned_pages_dec(); put_page(p); res = -EOPNOTSUPP; goto out; } + if (TestSetPageHWPoison(head)) + goto already_hwpoisoned; + + num_poisoned_pages_inc(); + /* * TODO: hwpoison for pud-sized hugetlb doesn't work right now, so * simply disable it. In order to make it work properly, we need @@ -1576,6 +1566,13 @@ static int memory_failure_hugetlb(unsigned long pfn, int flags) out: unlock_page(head); return res; +already_hwpoisoned: + unlock_page(head); + pr_err("Memory failure: %#lx: already hardware poisoned\n", pfn); + res = -EHWPOISON; + if (flags & MF_ACTION_REQUIRED) + res = kill_accessing_process(current, page_to_pfn(head), flags); + return res; } static int memory_failure_dev_pagemap(unsigned long pfn, int flags,