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=-5.7 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, 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 D483BC10F11 for ; Sat, 13 Apr 2019 07:08:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A24CD2084E for ; Sat, 13 Apr 2019 07:08:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726992AbfDMHIK (ORCPT ); Sat, 13 Apr 2019 03:08:10 -0400 Received: from mail-io1-f71.google.com ([209.85.166.71]:52527 "EHLO mail-io1-f71.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726457AbfDMHIJ (ORCPT ); Sat, 13 Apr 2019 03:08:09 -0400 Received: by mail-io1-f71.google.com with SMTP id p143so9763711iod.19 for ; Sat, 13 Apr 2019 00:08:09 -0700 (PDT) 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=wgy1m5VcgQGXtWKggy9ce0o1BeEi7R2JNRtZwDLowfg=; b=sZcSBEyFzlUc//ZTN/md+r2jyZJ6zYez1NIgzKhlpV3LEGBgX87/SNxloWSj945UmQ PFALskjOuMct4gE1vzG1TW2qNXZS7HXRmY3pL/mqQMf2akF54XdJ6DlN5tjI1QckYMtI EXJWFk/Y/N0kkiIZbY5a8z+5Zqu6l+UIx8KuBKUCZhS8JwokbXcB+zA1m5XO/hn+gVLv r+jh3NDUFXdwmnhnqAdAKgSZc2AFLfBQqdnQMVsfhAdUIOqYKuTt9gigwvy9YK/zl3gd zvgKT7MYGiaVL/L188c9ERJeI+jyGNouUbKK60onpuCEXzzmHpowdRD9BPhH52zAe7yD kLsg== X-Gm-Message-State: APjAAAWw+3MowTgqKLMXdUr065i+vM8LzPHMR2wXMkN0tjuh3SkFQzhD mzJdWqDI7rhWkIR+AB65hgXplc14OXUfFKM7f5Ikvj9vpmMe X-Google-Smtp-Source: APXvYqyOFO8FHvDkTPqrTnjgTeDz9yxe/k773oDUocLzi6jeX3/mIv1oOhl7MxcuSJfkDWhCOhkTSCSu/+b6KNeXB2ff3h65cVkv MIME-Version: 1.0 X-Received: by 2002:a02:5ec9:: with SMTP id h192mr11071140jab.2.1555139288638; Sat, 13 Apr 2019 00:08:08 -0700 (PDT) Date: Sat, 13 Apr 2019 00:08:08 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000e02bf505866414ae@google.com> Subject: INFO: task hung in do_exit From: syzbot To: ap420073@gmail.com, avagin@gmail.com, dbueso@suse.de, ebiederm@xmission.com, linux-kernel@vger.kernel.org, oleg@redhat.com, prsood@codeaurora.org, syzkaller-bugs@googlegroups.com, tj@kernel.org 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: 8ee15f32 Merge tag 'dma-mapping-5.1-1' of git://git.infrad.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15a512d3200000 kernel config: https://syzkaller.appspot.com/x/.config?x=4fb64439e07a1ec0 dashboard link: https://syzkaller.appspot.com/bug?extid=9880e421ec82313d6527 compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=149b89af200000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+9880e421ec82313d6527@syzkaller.appspotmail.com INFO: task syz-executor.4:13600 blocked for more than 143 seconds. Not tainted 5.1.0-rc4+ #65 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28384 13600 8046 0x80000000 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:285 [inline] rwsem_down_read_failed+0x213/0x420 kernel/locking/rwsem-xadd.c:302 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0x49/0x90 kernel/locking/rwsem.c:26 exit_mm kernel/exit.c:512 [inline] do_exit+0x443/0x2fa0 kernel/exit.c:863 do_group_exit+0x135/0x370 kernel/exit.c:980 __do_sys_exit_group kernel/exit.c:991 [inline] __se_sys_exit_group kernel/exit.c:989 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:989 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c29 Code: Bad RIP value. RSP: 002b:00007ffffcf8a138 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000000000000001e RCX: 0000000000458c29 RDX: 00000000004129e1 RSI: fffffffffffffff7 RDI: 0000000000000000 RBP: 0000000000000000 R08: 000000000009a64e R09: 00007ffffcf8a190 R10: 000000000009a64e R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffffcf8a190 R14: 0000000000000000 R15: 00007ffffcf8a1a0 INFO: task syz-executor.4:13603 blocked for more than 143 seconds. Not tainted 5.1.0-rc4+ #65 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28200 13603 8046 0x80000000 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:285 [inline] rwsem_down_read_failed+0x213/0x420 kernel/locking/rwsem-xadd.c:302 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0x49/0x90 kernel/locking/rwsem.c:26 exit_mm kernel/exit.c:512 [inline] do_exit+0x443/0x2fa0 kernel/exit.c:863 do_group_exit+0x135/0x370 kernel/exit.c:980 get_signal+0x399/0x1d50 kernel/signal.c:2577 do_signal+0x87/0x1940 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c29 Code: Bad RIP value. RSP: 002b:00007f55040dbcf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000073bf08 RCX: 0000000000458c29 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000073bf08 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000073bf0c R13: 00007ffffcf89f3f R14: 00007f55040dc9c0 R15: 000000000073bf0c Showing all locks held in the system: 1 lock held by khungtaskd/1042: #0: 00000000e7920387 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5061 1 lock held by rsyslogd/7885: #0: 00000000746102cf (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/7997: #0: 0000000084730aa3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000095194d1b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7998: #0: 00000000f2a2e523 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000c8e15d18 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7999: #0: 0000000070592706 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000a567a5f4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8000: #0: 0000000088e68b88 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000150e7fab (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8001: #0: 000000001f261fc9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000090482210 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8002: #0: 00000000003fc912 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000a81ef369 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8003: #0: 00000000620d61b3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000002d752e92 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.4/13600: #0: 0000000016ce688c (&mm->mmap_sem){++++}, at: exit_mm kernel/exit.c:512 [inline] #0: 0000000016ce688c (&mm->mmap_sem){++++}, at: do_exit+0x443/0x2fa0 kernel/exit.c:863 1 lock held by syz-executor.4/13603: #0: 0000000016ce688c (&mm->mmap_sem){++++}, at: exit_mm kernel/exit.c:512 [inline] #0: 0000000016ce688c (&mm->mmap_sem){++++}, at: do_exit+0x443/0x2fa0 kernel/exit.c:863 1 lock held by syz-executor.4/13611: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1042 Comm: khungtaskd Not tainted 5.1.0-rc4+ #65 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+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:288 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: --- This bug is generated by a bot. 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