From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f71.google.com (mail-pa0-f71.google.com [209.85.220.71]) by kanga.kvack.org (Postfix) with ESMTP id 861DD6B0260 for ; Fri, 29 Jul 2016 13:57:56 -0400 (EDT) Received: by mail-pa0-f71.google.com with SMTP id ag5so114748023pad.2 for ; Fri, 29 Jul 2016 10:57:56 -0700 (PDT) Received: from userp1040.oracle.com (userp1040.oracle.com. [156.151.31.81]) by mx.google.com with ESMTPS id q75si19440755pfi.216.2016.07.29.10.57.55 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 29 Jul 2016 10:57:55 -0700 (PDT) From: Vegard Nossum Subject: kernel BUG at mm/mempolicy.c:1699! Message-ID: <579B991C.9050809@oracle.com> Date: Fri, 29 Jul 2016 19:57:48 +0200 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov Cc: kasan-dev@googlegroups.com, LKML , Linux MM Hi guys, I ran into this one on commit c624c86615fb8aa61fa76ed8c935446d06c80e77: ------------[ cut here ]------------ kernel BUG at mm/mempolicy.c:1699! invalid opcode: 0000 [#1] PREEMPT SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) CPU: 1 PID: 27676 Comm: trinity-c0 Not tainted 4.7.0+ #64 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 task: ffff88010b055a00 task.stack: ffff880101fb0000 RIP: 0010:[] [] policy_zonelist+0xab/0x1a0 RSP: 0018:ffff880101fb7838 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000002000200 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff880103ef0690 RDI: ffff880103ef0694 RBP: ffff880101fb7858 R08: 000000000000000b R09: 0000000000000001 R10: 000000007d18a1c3 R11: 00000000b63bb1ad R12: 0000000002000200 R13: ffff88010b055a00 R14: 0000000000000000 R15: ffff880103ef0694 FS: 00007f405819e700(0000) GS:ffff88011ac80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001746770 CR3: 0000000004218000 CR4: 00000000000006e4 Stack: ffff880103ef0690 0000000002000200 ffff880103ef0690 0000000002000200 ffff880101fb78c0 ffffffff8146893a ffff880101fb78d0 0000000000015320 ffff88010b055a00 0000000000000000 ffff88010b056968 00000002030594a7 Call Trace: [] alloc_pages_current+0xba/0x370 [] depot_save_stack+0x3f4/0x490 [] save_stack+0xb5/0xd0 [] kasan_slab_free+0x9c/0xd0 [] kmem_cache_free+0xaf/0x2b0 [] __mpol_put+0x19/0x20 [] do_exit+0x1515/0x2c90 [] seccomp_phase1+0x68e/0x830 [] syscall_trace_enter_phase1+0x24c/0x500 [] syscall_trace_enter+0x64/0xb0 [] do_syscall_64+0x336/0x460 [] entry_SYSCALL64_slow_path+0x25/0x25 Code: db 0f 95 c0 48 89 c1 48 c1 e0 0b 48 c1 e1 04 48 89 ca 4a 03 14 e5 c0 58 84 84 48 83 c4 10 5b 41 5c 5d 48 8d 84 02 00 15 00 00 c3 <0f> 0b 48 8d 7e 06 48 b8 00 00 00 00 00 fc ff df 48 89 f9 48 c1 RIP [] policy_zonelist+0xab/0x1a0 RSP ---[ end trace a30466557ef07873 ]--- That's: $ addr2line -e runs/1469799091/vmlinux -i ffffffff8146246b ffffffff8146893a ffffffff81e136d4 ffffffff81476a65 ffffffff814770dc ffffffff814734ef ffffffff81465429 ffffffff81109c95 ffffffff812bf16e /home/vegard/linux/mm/mempolicy.c:1699 /home/vegard/linux/mm/mempolicy.c:2072 /home/vegard/linux/lib/stackdepot.c:247 /home/vegard/linux/mm/kasan/kasan.c:491 /home/vegard/linux/mm/kasan/kasan.c:496 /home/vegard/linux/mm/kasan/kasan.c:547 /home/vegard/linux/mm/slub.c:2940 /home/vegard/linux/mm/slub.c:2957 /home/vegard/linux/mm/mempolicy.c:300 /home/vegard/linux/kernel/exit.c:854 /home/vegard/linux/include/linux/audit.h:325 /home/vegard/linux/kernel/seccomp.c:536 /home/vegard/linux/kernel/seccomp.c:656 In particular, it's interesting that the kernel/exit.c line is mpol_put(tsk->mempolicy); and alloc_pages_current() does (potentially): pol = get_task_policy(current);. The bug seems very new or very rare or both. Vegard -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org