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=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,USER_AGENT_MUTT autolearn=ham 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 48C38C43218 for ; Mon, 10 Jun 2019 21:13:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1C72E20820 for ; Mon, 10 Jun 2019 21:13:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560201235; bh=nJDqIPZm/WjlT8tu0PmR59wXmBzWJFBaIPhYjPPrUgA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Sk67pi2NXQ+mTXPb889u/xTZ6pZHz7BuQ/o1TZIlCwTK+l/TxcmSj0kV1XqqF/nlF qOznYLR8VOrQuDj9icWc890cTGSItwvtVwT+x1j4E3M4ROUqM8SZhkie7pwwsDV+Q8 707IDR1fUiJKHNabmRQcESE3P886BnMrN9Qwb/FQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389959AbfFJVNy (ORCPT ); Mon, 10 Jun 2019 17:13:54 -0400 Received: from mx2.suse.de ([195.135.220.15]:35398 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2389636AbfFJVNy (ORCPT ); Mon, 10 Jun 2019 17:13:54 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 08689AAD0; Mon, 10 Jun 2019 21:13:51 +0000 (UTC) Date: Mon, 10 Jun 2019 23:13:50 +0200 From: Michal Hocko To: Minchan Kim Cc: Andrew Morton , linux-mm , LKML , stable@kernel.org, Wu Fangsuo , Pankaj Suryawanshi Subject: Re: [PATCH] mm: fix trying to reclaim unevicable LRU page Message-ID: <20190610211350.GD2388@dhcp22.suse.cz> References: <20190524071114.74202-1-minchan@kernel.org> <20190528151407.GE1658@dhcp22.suse.cz> <20190530024229.GF229459@google.com> <20190604122806.GH4669@dhcp22.suse.cz> <20190610094222.GA55602@google.com> <20190610103946.GE30967@dhcp22.suse.cz> <20190610112112.GE55602@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190610112112.GE55602@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 10-06-19 20:21:12, Minchan Kim wrote: [...] > >From 5cb8958ea240e2580bd2b331448009e8e1854240 Mon Sep 17 00:00:00 2001 > From: Minchan Kim > Date: Fri, 24 May 2019 15:54:10 +0900 > Subject: [PATCH] mm: fix trying to reclaim unevicable LRU page > > There was below bugreport from Wu Fangsuo. > > In CMA allocation path, isolate_migratepages_range could isolate unevictable > LRU pages and reclaim_clean_page_from_list can try to reclaim them if > they are clean file-backed pages. > > 7200 [ 680.491097] c4 7125 (syz-executor) page:ffffffbf02f33b40 count:86 mapcount:84 mapping:ffffffc08fa7a810 index:0x24 > 7201 [ 680.531186] c4 7125 (syz-executor) flags: 0x19040c(referenced|uptodate|arch_1|mappedtodisk|unevictable|mlocked) > 7202 [ 680.544987] c0 7125 (syz-executor) raw: 000000000019040c ffffffc08fa7a810 0000000000000024 0000005600000053 > 7203 [ 680.556162] c0 7125 (syz-executor) raw: ffffffc009b05b20 ffffffc009b05b20 0000000000000000 ffffffc09bf3ee80 > 7204 [ 680.566860] c0 7125 (syz-executor) page dumped because: VM_BUG_ON_PAGE(PageLRU(page) || PageUnevictable(page)) > 7205 [ 680.578038] c0 7125 (syz-executor) page->mem_cgroup:ffffffc09bf3ee80 > 7206 [ 680.585467] c0 7125 (syz-executor) ------------[ cut here ]------------ > 7207 [ 680.592466] c0 7125 (syz-executor) kernel BUG at /home/build/farmland/adroid9.0/kernel/linux/mm/vmscan.c:1350! > 7223 [ 680.603663] c0 7125 (syz-executor) Internal error: Oops - BUG: 0 [#1] PREEMPT SMP > 7224 [ 680.611436] c0 7125 (syz-executor) Modules linked in: > 7225 [ 680.616769] c0 7125 (syz-executor) CPU: 0 PID: 7125 Comm: syz-executor Tainted: G S 4.14.81 #3 > 7226 [ 680.626826] c0 7125 (syz-executor) Hardware name: ASR AQUILAC EVB (DT) > 7227 [ 680.633623] c0 7125 (syz-executor) task: ffffffc00a54cd00 task.stack: ffffffc009b00000 > 7228 [ 680.641917] c0 7125 (syz-executor) PC is at shrink_page_list+0x1998/0x3240 > 7229 [ 680.649144] c0 7125 (syz-executor) LR is at shrink_page_list+0x1998/0x3240 > 7230 [ 680.656303] c0 7125 (syz-executor) pc : [] lr : [] pstate: 60400045 > 7231 [ 680.666086] c0 7125 (syz-executor) sp : ffffffc009b05940 > .. > 7342 [ 681.671308] c0 7125 (syz-executor) [] shrink_page_list+0x1998/0x3240 > 7343 [ 681.679567] c0 7125 (syz-executor) [] reclaim_clean_pages_from_list+0x3c0/0x4f0 > 7344 [ 681.688793] c0 7125 (syz-executor) [] alloc_contig_range+0x3bc/0x650 > 7347 [ 681.717421] c0 7125 (syz-executor) [] cma_alloc+0x214/0x668 > 7348 [ 681.724892] c0 7125 (syz-executor) [] ion_cma_allocate+0x98/0x1d8 > 7349 [ 681.732872] c0 7125 (syz-executor) [] ion_alloc+0x200/0x7e0 > 7350 [ 681.740302] c0 7125 (syz-executor) [] ion_ioctl+0x18c/0x378 > 7351 [ 681.747738] c0 7125 (syz-executor) [] do_vfs_ioctl+0x17c/0x1780 > 7352 [ 681.755514] c0 7125 (syz-executor) [] SyS_ioctl+0xac/0xc0 > > Wu found it's due to [1]. Before that, unevictable page goes to cull_mlocked > routine so that it couldn't reach the VM_BUG_ON_PAGE line. > > To fix the issue, this patch filter out unevictable LRU pages > from the reclaim_clean_pages_from_list in CMA. > > [1] ad6b67041a45, mm: remove SWAP_MLOCK in ttu > > Cc: [4.12+] > Reported-debugged-by: Wu Fangsuo > Signed-off-by: Minchan Kim OK, this looks better. Thanks! Acked-by: Michal Hocko > --- > mm/vmscan.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index d9c3e873eca6..7350afae5c3c 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -1505,7 +1505,7 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, > > list_for_each_entry_safe(page, next, page_list, lru) { > if (page_is_file_cache(page) && !PageDirty(page) && > - !__PageMovable(page)) { > + !__PageMovable(page) && !PageUnevictable(page)) { > ClearPageActive(page); > list_move(&page->lru, &clean_pages); > } > -- > 2.22.0.rc2.383.gf4fbbf30c2-goog > -- Michal Hocko SUSE Labs