From patchwork Wed Sep 2 09:45:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oscar Salvador X-Patchwork-Id: 11750233 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D35F2109A for ; Wed, 2 Sep 2020 09:45:27 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9AF5F204EC for ; Wed, 2 Sep 2020 09:45:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9AF5F204EC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D1F096B0037; Wed, 2 Sep 2020 05:45:22 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id C7EEA6B0055; Wed, 2 Sep 2020 05:45:22 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B93726B005A; Wed, 2 Sep 2020 05:45:22 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0218.hostedemail.com [216.40.44.218]) by kanga.kvack.org (Postfix) with ESMTP id A25F36B0037 for ; Wed, 2 Sep 2020 05:45:22 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 689CA10FC8 for ; Wed, 2 Sep 2020 09:45:22 +0000 (UTC) X-FDA: 77217638484.10.brake87_5f0b0fc2709f Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin10.hostedemail.com (Postfix) with ESMTP id 3AD0816A0B9 for ; Wed, 2 Sep 2020 09:45:22 +0000 (UTC) X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,osalvador@suse.de,,RULES_HIT:30051:30054:30070:30083,0,RBL:195.135.220.15:@suse.de:.lbl8.mailshell.net-64.100.201.201 62.2.6.2;04yrqhbuxqkfm4pseifewn1a5oc9ioczx6xiuchmms4ttiekf1bs5m35isjgxzu.dih9k68hh1ij13juez4i5xtf6ejqnq6k4m8q4k4rxdqx9zy9wz9zc64rmbs4fbc.h-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:23,LUA_SUMMARY:none X-HE-Tag: brake87_5f0b0fc2709f X-Filterd-Recvd-Size: 2914 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf20.hostedemail.com (Postfix) with ESMTP for ; Wed, 2 Sep 2020 09:45:21 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 91A84B01E; Wed, 2 Sep 2020 09:45:21 +0000 (UTC) From: Oscar Salvador To: akpm@linux-foundation.org Cc: naoya.horiguchi@nec.com, mhocko@kernel.org, tony.luck@intel.com, cai@lca.pw, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Oscar Salvador Subject: [PATCH 3/4] mm,hwpoison: Drain pcplists before bailing out for non-buddy zero-refcount page Date: Wed, 2 Sep 2020 11:45:09 +0200 Message-Id: <20200902094510.10727-4-osalvador@suse.de> X-Mailer: git-send-email 2.13.7 In-Reply-To: <20200902094510.10727-1-osalvador@suse.de> References: <20200902094510.10727-1-osalvador@suse.de> X-Rspamd-Queue-Id: 3AD0816A0B9 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000011, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: A page with 0-refcount and !PageBuddy could perfectly be a pcppage. Currently, we bail out with an error if we encounter such a page, meaning that we do not handle pcppages neither from hard-offline nor from soft-offline path. Fix this by draining pcplists whenever we find this kind of page and retry the check again. It might be that pcplists have been spilled into the buddy allocator and so we can handle it. Signed-off-by: Oscar Salvador --- mm/memory-failure.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index d349dcb45056..62e0b7f30cd9 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -950,13 +950,13 @@ static int page_action(struct page_state *ps, struct page *p, } /** - * get_hwpoison_page() - Get refcount for memory error handling: + * __get_hwpoison_page() - Get refcount for memory error handling: * @page: raw error page (hit by memory error) * * Return: return 0 if failed to grab the refcount, otherwise true (some * non-zero value.) */ -static int get_hwpoison_page(struct page *page) +static int __get_hwpoison_page(struct page *page) { struct page *head = compound_head(page); @@ -986,6 +986,26 @@ static int get_hwpoison_page(struct page *page) return 0; } +static int get_hwpoison_page(struct page *p) +{ + int ret; + bool drained = false; + +retry: + ret = __get_hwpoison_page(p); + if (!ret && !is_free_buddy_page(p) && !page_count(p) && !drained) { + /* + * The page might be in a pcplist, so try to drain those + * and see if we are lucky. + */ + drain_all_pages(page_zone(p)); + drained = true; + goto retry; + } + + return ret; +} + /* * Do all that is necessary to remove user space mappings. Unmap * the pages and send SIGBUS to the processes if the data was dirty.