From patchwork Fri Oct 4 07:37:55 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miles Chen X-Patchwork-Id: 11173679 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 7C286112B for ; Fri, 4 Oct 2019 07:38:09 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 50EE9215EA for ; Fri, 4 Oct 2019 07:38:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 50EE9215EA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 88F876B0003; Fri, 4 Oct 2019 03:38:08 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 818FE8E0003; Fri, 4 Oct 2019 03:38:08 -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 736196B0008; Fri, 4 Oct 2019 03:38:08 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0249.hostedemail.com [216.40.44.249]) by kanga.kvack.org (Postfix) with ESMTP id 4A4F96B0003 for ; Fri, 4 Oct 2019 03:38:08 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id 0000F181AC9AE for ; Fri, 4 Oct 2019 07:38:07 +0000 (UTC) X-FDA: 76005298614.16.pan69_63efd1c728a44 X-Spam-Summary: 2,0,0,5d28d4010772f784,d41d8cd98f00b204,miles.chen@mediatek.com,:akpm@linux-foundation.org::linux-kernel@vger.kernel.org:linux-mediatek@lists.infradead.org:wsd_upstream@mediatek.com:miles.chen@mediatek.com:vbabka@suse.cz:mhocko@suse.com,RULES_HIT:41:355:379:541:800:960:973:988:989:1260:1277:1313:1314:1345:1431:1437:1516:1518:1534:1541:1711:1714:1730:1747:1777:1792:2198:2199:2393:2559:2562:2731:2895:3138:3139:3140:3141:3142:3351:3865:3866:3867:3868:3870:3872:4321:5007:6261:7875:7903:9592:10004:10400:11026:11473:11658:11914:12043:12114:12296:12297:12438:12521:12555:12679:12895:12986:13069:13161:13229:13311:13357:14096:14097:14181:14394:14721:21080:21324:21451:21627:30054:30070,0,RBL:210.61.82.184:@mediatek.com:.lbl8.mailshell.net-62.2.12.100 64.100.201.201,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: pan69_63efd1c728a44 X-Filterd-Recvd-Size: 3163 Received: from mailgw02.mediatek.com (unknown [210.61.82.184]) by imf03.hostedemail.com (Postfix) with ESMTP for ; Fri, 4 Oct 2019 07:38:06 +0000 (UTC) X-UUID: 4ac84daae92845f4b4b3b9b40615446e-20191004 X-UUID: 4ac84daae92845f4b4b3b9b40615446e-20191004 Received: from mtkcas09.mediatek.inc [(172.21.101.178)] by mailgw02.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.10 Build 0809 with TLS) with ESMTP id 482322489; Fri, 04 Oct 2019 15:37:57 +0800 Received: from mtkcas08.mediatek.inc (172.21.101.126) by mtkmbs07n2.mediatek.inc (172.21.101.141) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Fri, 4 Oct 2019 15:37:55 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas08.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Fri, 4 Oct 2019 15:37:55 +0800 From: Miles Chen To: Andrew Morton CC: , , , , Miles Chen , Vlastimil Babka , Michal Hocko Subject: [PATCH] mm/page_owner: fix incorrect looping in __set_page_owner_handle() Date: Fri, 4 Oct 2019 15:37:55 +0800 Message-ID: <20191004073755.3228-1-miles.chen@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 X-MTK: N X-Bogosity: Ham, tests=bogofilter, spamicity=0.000262, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: In __set_page_owner_handle(), we should loop over page [0...(1 << order) - 1] and setup their page_owner structures. Currently, __set_page_owner_handle() update page_ext at the end of the loop, sets the page_owner of (page + 0) twice and misses the page_owner of (page + (1 << order) - 1). Fix it by updating the page_ext at the start of the loop. In i == 0 case: for (i = 0; i < (1 << order); i++) { page_owner = get_page_owner(page_ext); <- page_ext belongs to page + 0 ... page_ext = lookup_page_ext(page + i); <- lookup_page_ext(page + 0) } Cc: Andrew Morton Cc: Vlastimil Babka Cc: Michal Hocko Signed-off-by: Miles Chen Fixes: 7e2f2a0cd17c ("mm, page_owner: record page owner for each subpage") --- mm/page_owner.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/mm/page_owner.c b/mm/page_owner.c index dee931184788..110c3e1987f2 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -178,6 +178,7 @@ static inline void __set_page_owner_handle(struct page *page, int i; for (i = 0; i < (1 << order); i++) { + page_ext = lookup_page_ext(page + i); page_owner = get_page_owner(page_ext); page_owner->handle = handle; page_owner->order = order; @@ -185,8 +186,6 @@ static inline void __set_page_owner_handle(struct page *page, page_owner->last_migrate_reason = -1; __set_bit(PAGE_EXT_OWNER, &page_ext->flags); __set_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags); - - page_ext = lookup_page_ext(page + i); } }