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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 6756BECE58C for ; Thu, 10 Oct 2019 02:36:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1A5CF2086D for ; Thu, 10 Oct 2019 02:36:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1A5CF2086D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 8DA8C8E0003; Wed, 9 Oct 2019 22:36:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 88A3F6B0005; Wed, 9 Oct 2019 22:36:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7A0838E0003; Wed, 9 Oct 2019 22:36:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0156.hostedemail.com [216.40.44.156]) by kanga.kvack.org (Postfix) with ESMTP id 59C386B0003 for ; Wed, 9 Oct 2019 22:36:24 -0400 (EDT) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with SMTP id D6DD2180AD805 for ; Thu, 10 Oct 2019 02:36:23 +0000 (UTC) X-FDA: 76026311046.08.month82_8ef4de2441536 X-HE-Tag: month82_8ef4de2441536 X-Filterd-Recvd-Size: 12274 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by imf42.hostedemail.com (Postfix) with ESMTP for ; Thu, 10 Oct 2019 02:36:22 +0000 (UTC) X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 09 Oct 2019 19:36:20 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,278,1566889200"; d="scan'208";a="393885850" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by fmsmga005.fm.intel.com with ESMTP; 09 Oct 2019 19:36:17 -0700 Date: Thu, 10 Oct 2019 10:36:01 +0800 From: Wei Yang To: Shakeel Butt Cc: Qian Cai , Wei Yang , Andrew Morton , Konstantin Khlebnikov , Rik van Riel , Linux MM , LKML , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , linux-s390@vger.kernel.org Subject: Re: "reuse mergeable anon_vma as parent when fork" causes a crash on s390 Message-ID: <20191010023601.GA4793@richard> Reply-To: Wei Yang References: <1570656570.5937.24.camel@lca.pw> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) 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: Hi, Qian, Shakeel Thanks for testing. Sounds I missed some case to handle. anon_vma_clone() now would be called in vma_adjust, which is a different case when it is introduced. BTW, do you have the specific test case? So that I could verify my change. The kernel build test doesn't trigger this. Thanks a lot :-) On Wed, Oct 09, 2019 at 03:21:11PM -0700, Shakeel Butt wrote: >On Wed, Oct 9, 2019 at 2:30 PM Qian Cai wrote: >> >> The linux-next commit "mm/rmap.c: reuse mergeable anon_vma as parent when fork" >> [1] causes a crash on s390 while compiling some C code. Reverted it fixes the >> issue. >> >> [1] https://lore.kernel.org/lkml/20191004160632.30251-1-richardw.yang@linux.intel.com/ >> >> 00: [ 330.681233] vma 0000000049a08008 start 000003ff8ee7f000 end 000003ff8eee4 >> 00: 000 >> 00: [ 330.681233] next 000000004f272008 prev 0000000065c84230 mm 0000000037d1c1 >> 00: 00 >> 00: [ 330.681233] prot 711 anon_vma 000000001f4e4a80 vm_ops 0000000000000000 >> 00: [ 330.681233] pgoff 3ff8ee7f file 0000000000000000 private_data 00000000000 >> 00: 00000 >> 00: [ 330.681233] flags: 0x8100073(read|write|mayread|maywrite|mayexec|account| >> 00: softdirty) >> 00: [ 330.681344] ------------[ cut here ]------------ >> 00: [ 330.681357] kernel BUG at include/linux/rmap.h:159! >> 00: [ 330.681442] illegal operation: 0001 ilc:1 [#1] SMP DEBUG_PAGEALLOC >> 00: [ 330.681460] Modules linked in: ip_tables x_tables xfs dasd_fba_mod dasd_e >> 00: ckd_mod dm_mirror dm_region_hash dm_log dm_mod >> 00: [ 330.681502] CPU: 0 PID: 7651 Comm: cc1 Not tainted 5.4.0-rc2-next-2019100 >> 00: 9+ #4 >> 00: [ 330.681516] Hardware name: IBM 2964 N96 400 (z/VM 6.4.0) >> 00: [ 330.681530] Krnl PSW : 0704c00180000000 00000000531d9cac (__vma_adjust+0x >> 00: cf4/0xf30) >> 00: [ 330.681561] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 >> 00: RI:0 EA:3 >> 00: [ 330.681579] Krnl GPRS: 0000000000000001 0000030000000000 0000000000000146 >> 00: 000000006cc03da4 >> 00: [ 330.681595] 0000030000000000 000000005304378c 00000000513de008 >> 00: 0000000000000000 >> 00: [ 330.681611] 0000000049a08008 0000000049a08080 0000000000000000 >> 00: 000000005a178438 >> 00: [ 330.681627] 0000000053bae3b0 0000000037d1c100 00000000531d9ca8 >> 00: 00000000235ef880 >> 01: HCPGSP2629I The virtual machine is placed in CP mode due to a SIGP stop from >> CPU 01. >> 01: HCPGSP2629I The virtual machine is placed in CP mode due to a SIGP stop from >> CPU 00. >> 00: [ 330.681668] Krnl Code: 00000000531d9c9c: fae0b9040028 ap 2308 >> 00: (15,%r11),40(1,%r0) >> 00: [ 330.681668] 00000000531d9ca2: c0e5ffff145f brasl %r14 >> 00: ,531bc560 >> 00: [ 330.681668] #00000000531d9ca8: a7f40001 brc 15,5 >> 00: 31d9caa >> 00: [ 330.681668] >00000000531d9cac: c020005f1a5a larl %r2, >> 00: 53dbd160 >> 00: [ 330.681668] 00000000531d9cb2: c0e50015ec2b brasl %r14 >> 00: ,53497508 >> 00: [ 330.681668] 00000000531d9cb8: e320f0d80004 lg %r2, >> 00: 216(%r15) >> 00: [ 330.681668] 00000000531d9cbe: c0e500040de1 brasl %r14 >> 00: ,5325b880 >> 00: [ 330.681668] 00000000531d9cc4: 4120d038 la %r2, >> 00: 56(%r13) >> 00: [ 330.682579] Call Trace: >> 00: [ 330.682665] ([<00000000531d9ca8>] __vma_adjust+0xcf0/0xf30) >> 00: [ 330.682684] [<00000000531da4f0>] vma_merge+0x608/0x6b8 >> 00: [ 330.682699] [<00000000531de3b8>] mmap_region+0x1e0/0x9b0 >> 00: [ 330.682713] [<00000000531defec>] do_mmap+0x464/0x650 >> 00: [ 330.682730] [<00000000531930ba>] vm_mmap_pgoff+0x132/0x1c0 >> 00: [ 330.682745] [<00000000531da7b4>] ksys_mmap_pgoff+0xd4/0x458 >> 00: [ 330.682761] [<00000000531dac54>] __s390x_sys_old_mmap+0xdc/0x108 >> 00: [ 330.682779] [<00000000537dcdd0>] system_call+0xd8/0x2b4 >> 00: [ 330.682791] INFO: lockdep is turned off. >> 00: [ 330.682801] Last Breaking-Event-Address: >> 00: [ 330.682815] [<00000000531d9ca8>] __vma_adjust+0xcf0/0xf30 >> 00: [ 330.682833] Kernel panic - not syncing: Fatal exception: panic_on_oops > >Our internal syzbot instance also hit this bug and bisected to the same patch. > >Report: > >[ 74.249839][ T8601] vma ffff88808c0f7eb0 start 0000000020000000 end >0000000021000000 >[ 74.249839][ T8601] next ffff888095f5e568 prev ffff888091279318 mm >ffff8880894555c0 >[ 74.249839][ T8601] prot 25 anon_vma ffff88809a9c4b40 vm_ops 0000000000000000 >[ 74.249839][ T8601] pgoff 20000 file 0000000000000000 private_data >0000000000000000 >[ 74.249839][ T8601] flags: >0x8100077(read|write|exec|mayread|maywrite|mayexec|account|softdirty) >[ 74.289454][ T8601] ------------[ cut here ]------------ >[ 74.294941][ T8601] kernel BUG at include/linux/rmap.h:159! >[ 74.301474][ T8601] invalid opcode: 0000 [#1] PREEMPT SMP KASAN >[ 74.307549][ T8601] CPU: 0 PID: 8601 Comm: syz-executor.0 Not >tainted 5.4.0-rc2-next-20191008 #0 >[ 74.316453][ T8601] Hardware name: Google Google Compute >Engine/Google Compute Engine, BIOS Google 01/01/2011 >[ 74.327161][ T8601] RIP: 0010:__vma_adjust+0x151c/0x1cc0 >[ 74.332604][ T8601] Code: 4c 89 ee 4c 89 f7 e8 b3 01 d2 ff 4d 39 ee >0f 82 1b fe ff ff 45 31 ed e9 1b fe ff ff e8 7d 00 d2 ff 48 8b 7d c8 >e8 76 62 fc ff <0f> 0b e8 6d 00 d2 ff 48 8b 85 68 ff ff ff 80 38 00 0f >85 20 07 00 >[ 74.352189][ T8601] RSP: 0018:ffff8880a0e9f9c0 EFLAGS: 00010286 >[ 74.358232][ T8601] RAX: 0000000000000147 RBX: dffffc0000000000 >RCX: 0000000000000000 >[ 74.366180][ T8601] RDX: 0000000000000000 RSI: ffffffff815cb676 >RDI: ffffed10141d3f12 >[ 74.374126][ T8601] RBP: ffff8880a0e9fa88 R08: 0000000000000147 >R09: ffffed1015d06161 >[ 74.382076][ T8601] R10: ffffed1015d06160 R11: ffff8880ae830b07 >R12: ffff888095f28e10 >[ 74.390054][ T8601] R13: ffff88808c0f7f18 R14: 0000000000000000 >R15: 0000000000000001 >[ 74.398014][ T8601] FS: 0000000000c57940(0000) >GS:ffff8880ae800000(0000) knlGS:0000000000000000 >[ 74.406918][ T8601] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >[ 74.413491][ T8601] CR2: 0000000020d06000 CR3: 0000000090f89000 >CR4: 00000000001406f0 >[ 74.421447][ T8601] DR0: 0000000000000000 DR1: 0000000000000000 >DR2: 0000000000000000 >[ 74.429403][ T8601] DR3: 0000000000000000 DR6: 00000000fffe0ff0 >DR7: 0000000000000400 >[ 74.437348][ T8601] Call Trace: >[ 74.440625][ T8601] vma_merge+0xb8a/0xe60 >[ 74.444848][ T8601] ? __vma_adjust+0x1cc0/0x1cc0 >[ 74.449677][ T8601] ? __sanitizer_cov_trace_cmp8+0x18/0x20 >[ 74.455369][ T8601] ? __vm_enough_memory+0x1b7/0x390 >[ 74.460542][ T8601] mmap_region+0x3e0/0x1760 >[ 74.465025][ T8601] ? __x64_sys_brk+0x760/0x760 >[ 74.469766][ T8601] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 >[ 74.475991][ T8601] ? get_unmapped_area+0x2ad/0x3d0 >[ 74.481075][ T8601] do_mmap+0x853/0x1190 >[ 74.485216][ T8601] vm_mmap_pgoff+0x1c5/0x230 >[ 74.489784][ T8601] ? randomize_stack_top+0x110/0x110 >[ 74.495044][ T8601] ? __kasan_check_read+0x11/0x20 >[ 74.500042][ T8601] ? _copy_to_user+0x118/0x160 >[ 74.504782][ T8601] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 >[ 74.511007][ T8601] ksys_mmap_pgoff+0xf7/0x630 >[ 74.515662][ T8601] ? find_mergeable_anon_vma+0x2e0/0x2e0 >[ 74.521295][ T8601] ? trace_hardirqs_on_thunk+0x1a/0x20 >[ 74.526735][ T8601] ? trace_hardirqs_on_thunk+0x1a/0x20 >[ 74.532181][ T8601] ? do_syscall_64+0x26/0x760 >[ 74.536835][ T8601] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe >[ 74.542881][ T8601] __x64_sys_mmap+0xe9/0x1b0 >[ 74.547448][ T8601] do_syscall_64+0xfa/0x760 >[ 74.551928][ T8601] entry_SYSCALL_64_after_hwframe+0x49/0xbe >[ 74.557796][ T8601] RIP: 0033:0x459a59 >[ 74.561682][ T8601] Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 >00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b >4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 >00 00 00 00 >[ 74.581261][ T8601] RSP: 002b:00007ffcc91b5068 EFLAGS: 00000246 >ORIG_RAX: 0000000000000009 >[ 74.589731][ T8601] RAX: ffffffffffffffda RBX: 0000000000000006 >RCX: 0000000000459a59 >[ 74.597685][ T8601] RDX: ffffffffefffffff RSI: 0000000000004000 >RDI: 0000000020196000 >[ 74.605632][ T8601] RBP: 000000000075bf20 R08: ffffffffffffffff >R09: 0000000000000000 >[ 74.613580][ T8601] R10: 0000000000008032 R11: 0000000000000246 >R12: 0000000000c57914 >[ 74.621527][ T8601] R13: 00000000004c6176 R14: 00000000004db118 >R15: 00000000ffffffff >[ 74.629486][ T8601] Modules linked in: >[ 74.636716][ T8601] ---[ end trace aa2e499bc1c6fb5e ]--- >[ 74.642235][ T8601] RIP: 0010:__vma_adjust+0x151c/0x1cc0 >[ 74.647787][ T8601] Code: 4c 89 ee 4c 89 f7 e8 b3 01 d2 ff 4d 39 ee >0f 82 1b fe ff ff 45 31 ed e9 1b fe ff ff e8 7d 00 d2 ff 48 8b 7d c8 >e8 76 62 fc ff <0f> 0b e8 6d 00 d2 ff 48 8b 85 68 ff ff ff 80 38 00 0f >85 20 07 00 >[ 74.667752][ T8601] RSP: 0018:ffff8880a0e9f9c0 EFLAGS: 00010286 >[ 74.673806][ T8601] RAX: 0000000000000147 RBX: dffffc0000000000 >RCX: 0000000000000000 >[ 74.681794][ T8601] RDX: 0000000000000000 RSI: ffffffff815cb676 >RDI: ffffed10141d3f12 >[ 74.689779][ T8601] RBP: ffff8880a0e9fa88 R08: 0000000000000147 >R09: ffffed1015d06161 >[ 74.698081][ T8601] R10: ffffed1015d06160 R11: ffff8880ae830b07 >R12: ffff888095f28e10 >[ 74.706052][ T8601] R13: ffff88808c0f7f18 R14: 0000000000000000 >R15: 0000000000000001 >[ 74.714061][ T8601] FS: 0000000000c57940(0000) >GS:ffff8880ae800000(0000) knlGS:0000000000000000 >[ 74.723209][ T8601] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >[ 74.729820][ T8601] CR2: 0000000020d06000 CR3: 0000000090f89000 >CR4: 00000000001406f0 >[ 74.738021][ T8601] DR0: 0000000000000000 DR1: 0000000000000000 >DR2: 0000000000000000 >[ 74.745972][ T8601] DR3: 0000000000000000 DR6: 00000000fffe0ff0 >DR7: 0000000000000400 >[ 74.753968][ T8601] Kernel panic - not syncing: Fatal exception > > >Syzbot reproducer: >mmap(&(0x7f0000196000/0x4000)=nil, 0x4000, PROT_NONE, 0x4032 /* flags= >MAP_NORESERVE|MAP_ANONYMOUS|MAP_FIXED|PROT_WRITE*/, -1, 0x0) >mmap(&(0x7f0000196000/0x4000)=nil, 0x4000, 0xffffffffefffffff, 0x8032 >/* flags= MAP_POPULATE|MAP_ANONYMOUS|MAP_FIXED|PROT_WRITE*/, -1, 0x0) > >Shakeel -- Wei Yang Help you, Help me