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=-5.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 959AFCA9EA0 for ; Mon, 4 Nov 2019 11:27:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 705B221744 for ; Mon, 4 Nov 2019 11:27:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728444AbfKDL1J (ORCPT ); Mon, 4 Nov 2019 06:27:09 -0500 Received: from mail-il1-f199.google.com ([209.85.166.199]:55273 "EHLO mail-il1-f199.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726364AbfKDL1J (ORCPT ); Mon, 4 Nov 2019 06:27:09 -0500 Received: by mail-il1-f199.google.com with SMTP id t67so6137946ill.21 for ; Mon, 04 Nov 2019 03:27:08 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=qF9HR4qzS9jnBK+P00Rhbp1bfWzTAJEf2Ve1RRYuzX4=; b=L0HsIOB94/iNACiJOGp1wqf3IolM8e6HxC1SZfgHMmtShiyCV4Q85W1me9ppMF3kny 50C3WhTnazR/a6yMSl0CG0Bp5wmWqWO0R99n7TSC8Z3Prqr3mZaXs10t1hkvPVXlwZV6 39ZU+bcpwdbq6cS319c/z/6f1JpvYOx9ZLqPEU6ZHVA6SbrY+kmcIpIcYkfPTEKHZpSV FO1S4uRuH585lyrpojEGv51UeV2Ws+76CjX5lzToVk+dXK3l5xz5yqUwW/w83Ahq85/3 YubK5HHDhdWMzUsXRQx54mm/STOGjCT/CmCjpBg4PKcDYtf59c0plfjAXfBwWZo0B1Se 1RoQ== X-Gm-Message-State: APjAAAVKz28y69Esj3AOXUcPdfzC60RcMul/HmTpHBifmjB5BZqrekoU 9nh4gC2i5k7mScdD6NVxDupmQkbFdpq5KELDULjc0I6a97T1 X-Google-Smtp-Source: APXvYqw8Ad//aE67c6FaVCE42SnBm/lXPgXLQ09URqePH9Tj+lqgsbdFJJhIjdUkshVKcnjmmf7XG67UIzdUEYO8HqkrLTZIIK8f MIME-Version: 1.0 X-Received: by 2002:a5d:8789:: with SMTP id f9mr1078590ion.237.1572866828188; Mon, 04 Nov 2019 03:27:08 -0800 (PST) Date: Mon, 04 Nov 2019 03:27:08 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000092c2f10596839808@google.com> Subject: KCSAN: data-race in mem_cgroup_select_victim_node / mem_cgroup_select_victim_node From: syzbot To: cgroups@vger.kernel.org, elver@google.com, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhocko@kernel.org, syzkaller-bugs@googlegroups.com, vdavydov.dev@gmail.com Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 05f22368 x86, kcsan: Enable KCSAN for x86 git tree: https://github.com/google/ktsan.git kcsan console output: https://syzkaller.appspot.com/x/log.txt?x=1774c6c0e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=87d111955f40591f dashboard link: https://syzkaller.appspot.com/bug?extid=234d50ad314ef67bcd16 compiler: gcc (GCC) 9.0.0 20181231 (experimental) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+234d50ad314ef67bcd16@syzkaller.appspotmail.com ================================================================== BUG: KCSAN: data-race in mem_cgroup_select_victim_node / mem_cgroup_select_victim_node write to 0xffff88809fade9b0 of 4 bytes by task 8603 on cpu 0: mem_cgroup_select_victim_node+0xb5/0x3d0 mm/memcontrol.c:1686 try_to_free_mem_cgroup_pages+0x175/0x4c0 mm/vmscan.c:3376 reclaim_high.constprop.0+0xf7/0x140 mm/memcontrol.c:2349 mem_cgroup_handle_over_high+0x96/0x180 mm/memcontrol.c:2430 tracehook_notify_resume include/linux/tracehook.h:197 [inline] exit_to_usermode_loop+0x20c/0x2c0 arch/x86/entry/common.c:163 prepare_exit_to_usermode+0x180/0x1a0 arch/x86/entry/common.c:194 swapgs_restore_regs_and_return_to_usermode+0x0/0x40 read to 0xffff88809fade9b0 of 4 bytes by task 7290 on cpu 1: mem_cgroup_select_victim_node+0x92/0x3d0 mm/memcontrol.c:1675 try_to_free_mem_cgroup_pages+0x175/0x4c0 mm/vmscan.c:3376 reclaim_high.constprop.0+0xf7/0x140 mm/memcontrol.c:2349 mem_cgroup_handle_over_high+0x96/0x180 mm/memcontrol.c:2430 tracehook_notify_resume include/linux/tracehook.h:197 [inline] exit_to_usermode_loop+0x20c/0x2c0 arch/x86/entry/common.c:163 prepare_exit_to_usermode+0x180/0x1a0 arch/x86/entry/common.c:194 swapgs_restore_regs_and_return_to_usermode+0x0/0x40 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7290 Comm: syz-executor.1 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ================================================================== Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 7290 Comm: syz-executor.1 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xf5/0x159 lib/dump_stack.c:113 panic+0x210/0x640 kernel/panic.c:221 kcsan_report.cold+0xc/0x10 kernel/kcsan/report.c:302 __kcsan_setup_watchpoint+0x32e/0x4a0 kernel/kcsan/core.c:411 __tsan_read4 kernel/kcsan/kcsan.c:35 [inline] __tsan_read4+0x2c/0x30 kernel/kcsan/kcsan.c:35 mem_cgroup_select_victim_node+0x92/0x3d0 mm/memcontrol.c:1675 try_to_free_mem_cgroup_pages+0x175/0x4c0 mm/vmscan.c:3376 reclaim_high.constprop.0+0xf7/0x140 mm/memcontrol.c:2349 mem_cgroup_handle_over_high+0x96/0x180 mm/memcontrol.c:2430 tracehook_notify_resume include/linux/tracehook.h:197 [inline] exit_to_usermode_loop+0x20c/0x2c0 arch/x86/entry/common.c:163 prepare_exit_to_usermode+0x180/0x1a0 arch/x86/entry/common.c:194 retint_user+0x8/0x8 RIP: 0033:0x45862a Code: 48 85 db 74 b6 41 bc ca 00 00 00 eb 0c 0f 1f 00 48 8b 5b 08 48 85 db 74 a2 48 8b 3b 48 8b 47 10 48 85 c0 74 05 ff d0 48 8b 3b ff 4f 28 0f 94 c0 84 c0 74 db 8b 47 2c 85 c0 74 d4 45 31 d2 ba RSP: 002b:00007ffec3569600 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00007ffec3569600 RCX: 00000000004584ca RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000a76d48 RBP: 00007ffec3569640 R08: 0000000000000001 R09: 000000000269f940 R10: 000000000269fc10 R11: 0000000000000246 R12: 00000000000000ca R13: 0000000000000079 R14: 0000000000000000 R15: 00007ffec3569690 Kernel Offset: disabled Rebooting in 86400 seconds.. --- This bug is generated by a bot. 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