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=-6.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 87DBAC433E1 for ; Fri, 21 Aug 2020 08:01:32 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 345F42078D for ; Fri, 21 Aug 2020 08:01:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 345F42078D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 985518D0016; Fri, 21 Aug 2020 04:01:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 936B08D0006; Fri, 21 Aug 2020 04:01:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 84CA48D0016; Fri, 21 Aug 2020 04:01:31 -0400 (EDT) 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 70CF78D0006 for ; Fri, 21 Aug 2020 04:01:31 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 40D4A824556B for ; Fri, 21 Aug 2020 08:01:30 +0000 (UTC) X-FDA: 77173831140.02.cry61_290965b27037 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin02.hostedemail.com (Postfix) with ESMTP id 0D19F10097AA0 for ; Fri, 21 Aug 2020 08:01:30 +0000 (UTC) X-HE-Tag: cry61_290965b27037 X-Filterd-Recvd-Size: 6920 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf15.hostedemail.com (Postfix) with ESMTP for ; Fri, 21 Aug 2020 08:01:29 +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 261FBAD85; Fri, 21 Aug 2020 08:01:56 +0000 (UTC) Date: Fri, 21 Aug 2020 10:01:27 +0200 From: Michal Hocko To: Qian Cai Cc: Alex Shi , akpm@linux-foundation.org, Johannes Weiner , Vladimir Davydov , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [Resend PATCH 1/6] mm/memcg: warning on !memcg after readahead page charged Message-ID: <20200821080127.GD32537@dhcp22.suse.cz> References: <1597144232-11370-1-git-send-email-alex.shi@linux.alibaba.com> <20200820145850.GA4622@lca.pw> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200820145850.GA4622@lca.pw> X-Rspamd-Queue-Id: 0D19F10097AA0 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam01 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 20-08-20 10:58:51, Qian Cai wrote: > On Tue, Aug 11, 2020 at 07:10:27PM +0800, Alex Shi wrote: > > Since readahead page is charged on memcg too, in theory we don't have to > > check this exception now. Before safely remove them all, add a warning > > for the unexpected !memcg. > > > > Signed-off-by: Alex Shi > > Acked-by: Michal Hocko > > This will trigger, Thanks for the report! > [ 1863.916499] LTP: starting move_pages12 > [ 1863.946520] page:000000008ccc1062 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1fd3c0 > [ 1863.946553] head:000000008ccc1062 order:5 compound_mapcount:0 compound_pincount:0 Hmm, this is really unexpected. How did we get order-5 page here? Is this some special mappaing that sys_move_pages should just ignore? > [ 1863.946568] anon flags: 0x7fff800001000d(locked|uptodate|dirty|head) > [ 1863.946584] raw: 007fff800001000d c000000016ebfcd8 c000000016ebfcd8 c000001feaf46d59 > [ 1863.946609] raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 > [ 1863.946632] page dumped because: VM_WARN_ON_ONCE_PAGE(!memcg) > [ 1863.946669] ------------[ cut here ]------------ > [ 1863.946694] WARNING: CPU: 16 PID: 35307 at mm/memcontrol.c:6908 mem_cgroup_migrate+0x5f8/0x610 > [ 1863.946708] Modules linked in: vfio_pci vfio_virqfd vfio_iommu_spapr_tce vfio vfio_spapr_eeh loop kvm_hv kvm ip_tables x_tables sd_mod bnx2x tg3 ahci libahci libphy mdio firmware_class libata dm_mirror dm_region_hash dm_log dm_mod > [ 1863.946801] CPU: 16 PID: 35307 Comm: move_pages12 Not tainted 5.9.0-rc1-next-20200820 #4 > [ 1863.946834] NIP: c0000000003fcb48 LR: c0000000003fcb38 CTR: 0000000000000000 > [ 1863.946856] REGS: c000000016ebf6f0 TRAP: 0700 Not tainted (5.9.0-rc1-next-20200820) > [ 1863.946879] MSR: 900000000282b033 CR: 28242882 XER: 00000000 > [ 1863.946915] CFAR: c00000000032c644 IRQMASK: 0 > GPR00: c0000000003fcb38 c000000016ebf980 c000000005923200 0000000000000031 > GPR04: 0000000000000000 0000000000000000 0000000000000027 c000001ffd727190 > GPR08: 0000000000000023 0000000000000001 c0000000058f3200 0000000000000001 > GPR12: 0000000000002000 c000001ffffe3800 c000000000b26a68 0000000000000000 > GPR16: c000000016ebfc20 c000000016ebfcd8 0000000000000020 0000000000000001 > GPR20: c00c00080724f000 c0000000003c8770 0000000000000000 c000000016ebfcd0 > GPR24: 0000000000000000 fffffffffffffff5 0000000000000002 0000000000000000 > GPR28: 0000000000000000 0000000000000001 0000000000000000 c00c000007f4f000 > [ 1863.947142] NIP [c0000000003fcb48] mem_cgroup_migrate+0x5f8/0x610 > [ 1863.947164] LR [c0000000003fcb38] mem_cgroup_migrate+0x5e8/0x610 > [ 1863.947185] Call Trace: > [ 1863.947203] [c000000016ebf980] [c0000000003fcb38] mem_cgroup_migrate+0x5e8/0x610 (unreliable) > [ 1863.947241] [c000000016ebf9c0] [c0000000003c9080] migrate_page_states+0x4e0/0xce0 > [ 1863.947274] [c000000016ebf9f0] [c0000000003cbbec] migrate_page+0x8c/0x120 > [ 1863.947307] [c000000016ebfa30] [c0000000003ccf10] move_to_new_page+0x190/0x670 > [ 1863.947341] [c000000016ebfaf0] [c0000000003ced08] migrate_pages+0xfb8/0x1880 > [ 1863.947365] [c000000016ebfc00] [c0000000003cf670] move_pages_and_store_status.isra.45+0xa0/0x160 > [ 1863.947399] [c000000016ebfc80] [c0000000003cfef4] sys_move_pages+0x7c4/0xed0 > [ 1863.947434] [c000000016ebfdc0] [c00000000002c678] system_call_exception+0xf8/0x1d0 > [ 1863.947459] [c000000016ebfe20] [c00000000000d0a8] system_call_common+0xe8/0x218 > [ 1863.947481] Instruction dump: > [ 1863.947502] 7fc3f378 4bfee82d 7c0802a6 3c82fb20 7fe3fb78 38844fc8 f8010050 4bf2fad5 > [ 1863.947527] 60000000 39200001 3d42fffd 992a82fb <0fe00000> e8010050 eb810020 7c0803a6 > [ 1863.947563] CPU: 16 PID: 35307 Comm: move_pages12 Not tainted 5.9.0-rc1-next-20200820 #4 > [ 1863.947594] Call Trace: > [ 1863.947615] [c000000016ebf4d0] [c0000000006f6008] dump_stack+0xfc/0x174 (unreliable) > [ 1863.947642] [c000000016ebf520] [c0000000000c9004] __warn+0xc4/0x14c > [ 1863.947665] [c000000016ebf5b0] [c0000000006f4b68] report_bug+0x108/0x1f0 > [ 1863.947689] [c000000016ebf650] [c0000000000234f4] program_check_exception+0x104/0x2e0 > [ 1863.947724] [c000000016ebf680] [c000000000009664] program_check_common_virt+0x2c4/0x310 > [ 1863.947751] --- interrupt: 700 at mem_cgroup_migrate+0x5f8/0x610 > LR = mem_cgroup_migrate+0x5e8/0x610 > [ 1863.947786] [c000000016ebf9c0] [c0000000003c9080] migrate_page_states+0x4e0/0xce0 > [ 1863.947810] [c000000016ebf9f0] [c0000000003cbbec] migrate_page+0x8c/0x120 > [ 1863.947843] [c000000016ebfa30] [c0000000003ccf10] move_to_new_page+0x190/0x670 > [ 1863.947867] [c000000016ebfaf0] [c0000000003ced08] migrate_pages+0xfb8/0x1880 > [ 1863.947901] [c000000016ebfc00] [c0000000003cf670] move_pages_and_store_status.isra.45+0xa0/0x160 > [ 1863.947936] [c000000016ebfc80] [c0000000003cfef4] sys_move_pages+0x7c4/0xed0 > [ 1863.947969] [c000000016ebfdc0] [c00000000002c678] system_call_exception+0xf8/0x1d0 > [ 1863.948002] [c000000016ebfe20] [c00000000000d0a8] system_call_common+0xe8/0x218 > [ 1863.948034] irq event stamp: 410 > [ 1863.948054] hardirqs last enabled at (409): [] console_unlock+0x6b4/0x990 > [ 1863.948092] hardirqs last disabled at (410): [] program_check_common_virt+0x2bc/0x310 > [ 1863.948126] softirqs last enabled at (0): [] copy_process+0x788/0x1950 > [ 1863.948229] softirqs last disabled at (0): [<0000000000000000>] 0x0 > [ 1863.948316] ---[ end trace 74f8f4df751b0259 ]--- -- Michal Hocko SUSE Labs