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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 E8333C07E96 for ; Thu, 15 Jul 2021 15:23:20 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8A4C3613CC for ; Thu, 15 Jul 2021 15:23:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8A4C3613CC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 915298D00D9; Thu, 15 Jul 2021 11:23:20 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8C5AC8D00CD; Thu, 15 Jul 2021 11:23:20 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 78D8C8D00D9; Thu, 15 Jul 2021 11:23:20 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 594828D00CD for ; Thu, 15 Jul 2021 11:23:20 -0400 (EDT) Received: from smtpin32.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 3C3218248D52 for ; Thu, 15 Jul 2021 15:23:19 +0000 (UTC) X-FDA: 78365190918.32.35F3015 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf04.hostedemail.com (Postfix) with ESMTP id 852A550000A9 for ; Thu, 15 Jul 2021 15:23:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=M5BuhxlRetjxwk3aIO2mhdXoXwLCgAo192GMMEmNGHQ=; b=btpOYnTLgWRM14ebatKKky+imq Tfkge9+tYk2iLN/UmStntyXetYyR8tWpRBjsNmSwZ76emVQLFGYods1wVzIk3ij6sjnkxucMSPzsp ULPRBwr0vqRBIB2ZsNF1kceZOHvCfAZYqhvNyTS3tyRm2mk/fjR3AXR/zdH0Eh8Ls8nyGi/1e0T58 RdniPWXJhUpg3nWuFibb2OauWA9Nju2HE8T29htnHN8uYTa3D//U0C9bzSiZ2fJXRO7VY+0kicVAB OVA8wc7fOX0ChLTL+6MuMnSxvwtISfqJHbGPtZyu+5QgSkg2LNn9vwh4o+qLz2EvM3lRsZiyPAV65 oG5S71FQ==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1m43CC-003TBY-TF; Thu, 15 Jul 2021 15:22:47 +0000 Date: Thu, 15 Jul 2021 16:22:40 +0100 From: Matthew Wilcox To: Bin Wang Cc: linux-mm@kvack.org, naoya.horiguchi@nec.com, akpm@linux-foundation.org, wuxu.wu@huawei.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/hwpoison: dissolve error hugepages of file mapping Message-ID: References: <20210715150852.1655-1-wangbin224@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210715150852.1655-1-wangbin224@huawei.com> Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=btpOYnTL; spf=none (imf04.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none X-Stat-Signature: 51o3p5weai9agesyen9rykh9qomxzh7t X-Rspamd-Queue-Id: 852A550000A9 X-Rspamd-Server: rspam01 X-HE-Tag: 1626362597-144536 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 Thu, Jul 15, 2021 at 11:08:52PM +0800, Bin Wang wrote: > We handle error on hugetlb file with hugetlbfs_error_remove_page(), > which removes the error hugepages from page cache. And with the > HWPoison flag in head page, it is safe to free the error hugepages > and dissolve it. How is that safe? If you're going to dissolve the huge page, you need to figure out which subpage needs to have the HWPoison flag set.