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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id C491BC433F5 for ; Wed, 9 Mar 2022 21:30:15 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3C4988D0002; Wed, 9 Mar 2022 16:30:15 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 3729B8D0001; Wed, 9 Mar 2022 16:30:15 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2617B8D0002; Wed, 9 Mar 2022 16:30:15 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0239.hostedemail.com [216.40.44.239]) by kanga.kvack.org (Postfix) with ESMTP id 129AF8D0001 for ; Wed, 9 Mar 2022 16:30:15 -0500 (EST) Received: from smtpin31.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id C88C49BBB8 for ; Wed, 9 Mar 2022 21:30:14 +0000 (UTC) X-FDA: 79226141148.31.4A416B4 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf10.hostedemail.com (Postfix) with ESMTP id 2988CC0014 for ; Wed, 9 Mar 2022 21:30:13 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id CB9E0B81EE7; Wed, 9 Mar 2022 21:30:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 519B6C340E8; Wed, 9 Mar 2022 21:30:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1646861411; bh=6Ug4WPjHsFmglkEyi2rRA7H01NYuecKpr79IHLkSjHQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=O7unKhH89e3MIf0JVKGuLMfBLZMwb7Lu0cuU6MplWZLCNvOsw3dzGuSO2SmfGy+f6 KCkpOi1L7oGEBgn6A3nvVoSvvx/DymaIXjUXAroxieROL1u3VIwO0UvUQQ+HqTatyG crjBYc4Cayn52nqnhF1vMepqwTKr/gJUaXPEhukw= Date: Wed, 9 Mar 2022 13:30:10 -0800 From: Andrew Morton To: Naoya Horiguchi Cc: linux-mm@kvack.org, Mike Kravetz , Miaohe Lin , Yang Shi , Naoya Horiguchi , linux-kernel@vger.kernel.org Subject: Re: [PATCH v1] mm/hwpoison: set PageHWPoison after taking page lock in memory_failure_hugetlb() Message-Id: <20220309133010.0f04c2ac4939edbdb35723bb@linux-foundation.org> In-Reply-To: <20220309091449.2753904-1-naoya.horiguchi@linux.dev> References: <20220309091449.2753904-1-naoya.horiguchi@linux.dev> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 2988CC0014 X-Stat-Signature: xd3gnc3p1x5oydxty4xwn54chccd4fdw Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=O7unKhH8; spf=pass (imf10.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-HE-Tag: 1646861413-951871 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: On Wed, 9 Mar 2022 18:14:49 +0900 Naoya Horiguchi wrote: > 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, What are the runtime effects of this? Do we think a -stable backport is needed? Are we missing a reported-by here? I'm too lazy to hunt down who it was.