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,LOTS_OF_MONEY,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS 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 9C8D7C2D0BF for ; Tue, 17 Dec 2019 20:43:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 77ADA21D7D for ; Tue, 17 Dec 2019 20:43:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728451AbfLQUnL (ORCPT ); Tue, 17 Dec 2019 15:43:11 -0500 Received: from mail-il1-f197.google.com ([209.85.166.197]:36878 "EHLO mail-il1-f197.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728425AbfLQUnL (ORCPT ); Tue, 17 Dec 2019 15:43:11 -0500 Received: by mail-il1-f197.google.com with SMTP id t19so10427388ila.4 for ; Tue, 17 Dec 2019 12:43:09 -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=ZsG4GGhI1HdtobOHo0iYGQ381sBQZXGjK6JsTLf54tI=; b=tvoUqA3uOQBkcmKbl5Gm5FZbNNV0yQT9pFKECYdbLjBA0nW2WlXfZ/yEZMDT7vWU4u kzCPkc2fioBsGOt+jVsdxibg4SlYU4cKxVYsY6TAPCQQdL6zlqxPIodIBTbm5tjxCHDV gFjzPP9pFWjt53tEu8JxhejrV7UchwPZ16iVGeTDFKZcumHkgm7LINDi0lP7sBGGRNp4 WFllTR7Q99jzzZ37kukpAy/BpujxzGhON9qeAU5vnqm3IhhIjX1sOR3+CJnGGP1Co/TC x/C9K9dYS0z6lm7S4R42Ntv5Z2Teyg4ZppdrRnHDKbemZx5+iEqoZcMxPyS55Nd7Y+fV c8Rw== X-Gm-Message-State: APjAAAU4OPn6W5aLjeeznQtc/hnsHNFTGxg6qUGNYw0UoKZ7KWUfKir/ Vv8H6YMYuOXRiGowd9S2wdBwM5epBMuevWzu4s2GVj4xensc X-Google-Smtp-Source: APXvYqyu7jeTkwiEQsSvZo2qq1J2Cge2aNKRqMbtsXfHs+JssScBIJRW+W5oExAps69/GWTSttKC9a6p9iUPVSEaeSZY/T6eo+Tx MIME-Version: 1.0 X-Received: by 2002:a5e:8417:: with SMTP id h23mr5163006ioj.17.1576615388758; Tue, 17 Dec 2019 12:43:08 -0800 (PST) Date: Tue, 17 Dec 2019 12:43:08 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000031cefb0599ec600b@google.com> Subject: KCSAN: data-race in poll_schedule_timeout.constprop.0 / pollwake (3) From: syzbot To: elver@google.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 245a4300 Merge branch 'rcu/kcsan' into tip/locking/kcsan git tree: https://github.com/google/ktsan.git kcsan console output: https://syzkaller.appspot.com/x/log.txt?x=11beba8ee00000 kernel config: https://syzkaller.appspot.com/x/.config?x=a38292766f8efdaa dashboard link: https://syzkaller.appspot.com/bug?extid=9b3fb64bcc8c1d807595 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+9b3fb64bcc8c1d807595@syzkaller.appspotmail.com ================================================================== BUG: KCSAN: data-race in poll_schedule_timeout.constprop.0 / pollwake write to 0xffffc90001043c30 of 4 bytes by task 17695 on cpu 0: __pollwake fs/select.c:197 [inline] pollwake+0xe3/0x140 fs/select.c:217 __wake_up_common+0x7b/0x180 kernel/sched/wait.c:93 __wake_up_common_lock+0x77/0xb0 kernel/sched/wait.c:123 __wake_up+0xe/0x10 kernel/sched/wait.c:142 signalfd_notify include/linux/signalfd.h:22 [inline] signalfd_notify include/linux/signalfd.h:19 [inline] __send_signal+0x70e/0x870 kernel/signal.c:1158 send_signal+0x224/0x2b0 kernel/signal.c:1236 __group_send_sig_info kernel/signal.c:1275 [inline] do_notify_parent+0x55b/0x5e0 kernel/signal.c:1992 exit_notify kernel/exit.c:670 [inline] do_exit+0x16ef/0x18c0 kernel/exit.c:818 do_group_exit+0xb4/0x1c0 kernel/exit.c:895 __do_sys_exit_group kernel/exit.c:906 [inline] __se_sys_exit_group kernel/exit.c:904 [inline] __x64_sys_exit_group+0x2e/0x30 kernel/exit.c:904 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffffc90001043c30 of 4 bytes by task 15995 on cpu 1: poll_schedule_timeout.constprop.0+0x50/0xc0 fs/select.c:242 do_poll fs/select.c:951 [inline] do_sys_poll+0x66d/0x990 fs/select.c:1001 __do_sys_poll fs/select.c:1059 [inline] __se_sys_poll fs/select.c:1047 [inline] __x64_sys_poll+0x10f/0x250 fs/select.c:1047 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 15995 Comm: udevd Not tainted 5.5.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ================================================================== --- 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.