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=unavailable 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 ECBA4CA9EA0 for ; Mon, 4 Nov 2019 11:29:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CDD25222C1 for ; Mon, 4 Nov 2019 11:29:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728648AbfKDL3K (ORCPT ); Mon, 4 Nov 2019 06:29:10 -0500 Received: from mail-io1-f72.google.com ([209.85.166.72]:38813 "EHLO mail-io1-f72.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727782AbfKDL3K (ORCPT ); Mon, 4 Nov 2019 06:29:10 -0500 Received: by mail-io1-f72.google.com with SMTP id c2so12925178ioc.5 for ; Mon, 04 Nov 2019 03:29:08 -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=RIm6RUmV98ceI6JpEEZxU6F8gTuyxH9inbdlIYhEiEE=; b=RD+q4S6yvBY23JxKXTw0J6cS94dhL2qe8j5RNMmu63kmRPywenx5Hx4AARhdZ2oq/J dy8Eh75igeME2ApqORCYCNpYoHRiSgT6D4KMXavkWcGc10aij1/b9lQ8H50Nybhf6G9L wTCUvxoWhQ+wRHbEx2J0n10Ynaav7Fgrbla1ky1BibMVMWujdEFI5rrhjD0rq+8DYO+V J/MQAwY0T+3PZUWesb3VdDZJll8yMsJK7Uq8wfn4npLWrlhZsAMT3dgPmWpNlmvyNS93 W6k3LJFdXDFinpydiYcNaBTV5+KqtlHMvZ/PtmTEX6PxFCQOfKa5tkxC1odEYYDsYlzY Okug== X-Gm-Message-State: APjAAAW77x5rsFkUdmBpSMuHlCVwyDpUX9V8XdJGullG4oLBXGwJuzC7 f68ZsqQLbsTZIXdDzGhma1E5m/OuGfHFnA4MFocDT1QsU4TN X-Google-Smtp-Source: APXvYqxuMRooZI5EVRwo9a2FtTxWSKBlbUNC3S+1y488ojt53I2BesR3VcyVnHGw27gL3vdrKMwKKXrA0YrYbfmYif4c1ZYsljLJ MIME-Version: 1.0 X-Received: by 2002:a02:9f8b:: with SMTP id a11mr1433768jam.10.1572866947906; Mon, 04 Nov 2019 03:29:07 -0800 (PST) Date: Mon, 04 Nov 2019 03:29:07 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000b587670596839fab@google.com> Subject: KCSAN: data-race in process_srcu / synchronize_srcu From: syzbot To: axboe@kernel.dk, elver@google.com, justin@coraid.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@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=17ade7ef600000 kernel config: https://syzkaller.appspot.com/x/.config?x=87d111955f40591f dashboard link: https://syzkaller.appspot.com/bug?extid=08f3e9d26e5541e1ecf2 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+08f3e9d26e5541e1ecf2@syzkaller.appspotmail.com ================================================================== BUG: KCSAN: data-race in process_srcu / synchronize_srcu write to 0xffffffff8604e8a0 of 8 bytes by task 17 on cpu 1: srcu_gp_end kernel/rcu/srcutree.c:533 [inline] srcu_advance_state kernel/rcu/srcutree.c:1146 [inline] process_srcu+0x207/0x780 kernel/rcu/srcutree.c:1237 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269 worker_thread+0xa0/0x800 kernel/workqueue.c:2415 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 read to 0xffffffff8604e8a0 of 8 bytes by task 12515 on cpu 0: srcu_might_be_idle kernel/rcu/srcutree.c:784 [inline] synchronize_srcu+0x107/0x214 kernel/rcu/srcutree.c:996 fsnotify_connector_destroy_workfn+0x63/0xb0 fs/notify/mark.c:164 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269 worker_thread+0xa0/0x800 kernel/workqueue.c:2415 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 12515 Comm: kworker/u4:8 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound fsnotify_connector_destroy_workfn ================================================================== Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 12515 Comm: kworker/u4:8 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound fsnotify_connector_destroy_workfn 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_read8 kernel/kcsan/kcsan.c:36 [inline] __tsan_read8+0x2c/0x30 kernel/kcsan/kcsan.c:36 srcu_might_be_idle kernel/rcu/srcutree.c:784 [inline] synchronize_srcu+0x107/0x214 kernel/rcu/srcutree.c:996 fsnotify_connector_destroy_workfn+0x63/0xb0 fs/notify/mark.c:164 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269 worker_thread+0xa0/0x800 kernel/workqueue.c:2415 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Kernel Offset: disabled Rebooting in 86400 seconds.. --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.