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=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 7379FC4321A for ; Sun, 28 Apr 2019 18:14:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4232020679 for ; Sun, 28 Apr 2019 18:14:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727130AbfD1SOI (ORCPT ); Sun, 28 Apr 2019 14:14:08 -0400 Received: from mail-io1-f69.google.com ([209.85.166.69]:54919 "EHLO mail-io1-f69.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726999AbfD1SOH (ORCPT ); Sun, 28 Apr 2019 14:14:07 -0400 Received: by mail-io1-f69.google.com with SMTP id c17so7182643iom.21 for ; Sun, 28 Apr 2019 11:14:07 -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:in-reply-to:message-id:subject :from:to; bh=2djQxR0Pmm/Dma5dasUwGKjuaJruPxPF0g/tYd5DCVw=; b=Z/VMwtL19HaKTJqeHJpslEoADjJjJ+EsiV1oNGRYI2F5OXvXHDHcCuYsvrtWXDOSXu KYOx3andpBVurNfSe+La4mI4npY3yq4J/RDFM32CYeUfBIFBZY1J7Rk1sPOdxOXTLmf4 ckOmWyqSL86x6fPhdEQptaYSdxI82rp3D2tPahgaVKjzJlRGVNaNewkB11n4CjAe5LVt /VTDzBjnsvOc2aJaQw5qhyzxzZ/KaFa8l1quDjO0P1rjIfJcZctNkmU4F0VwuJ06N9kM w81+qml4LTI7Da4KbcwkIlGxbF6bYi8drVhKL6NXK6/JIZ/Up9nqG+5zgNKYYRkxqTAj NQ5g== X-Gm-Message-State: APjAAAW5lZmNI/uqRyl85e4u9F9Ta6OY4ANxOJV94Ra6KxfzAwa26rCp H6q9HmQRj98PS/WjCPZJB4HdqRx4CQY+gKOrMZB2RkUp5V5Y X-Google-Smtp-Source: APXvYqyUNImUi4bZYKTPXLruu31pr12MtImbQeiPnmmCKBTFsDTE6aysY6zZBiuKpG1aGdDeiU7NXrLuQoLr0YlkJ3tRgwivVO2c MIME-Version: 1.0 X-Received: by 2002:a02:a1d6:: with SMTP id o22mr17605551jah.102.1556475246593; Sun, 28 Apr 2019 11:14:06 -0700 (PDT) Date: Sun, 28 Apr 2019 11:14:06 -0700 In-Reply-To: <001a113ed5540f411c0568cc8418@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000002cd22305879b22c4@google.com> Subject: Re: INFO: task hung in __get_super From: syzbot To: axboe@kernel.dk, dvyukov@google.com, jack@suse.cz, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, penguin-kernel@I-love.SAKURA.ne.jp, penguin-kernel@i-love.sakura.ne.jp, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk 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 syzbot has found a reproducer for the following crash on: HEAD commit: 037904a2 Merge branch 'x86-urgent-for-linus' of git://git... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=135ff034a00000 kernel config: https://syzkaller.appspot.com/x/.config?x=a42d110b47dd6b36 dashboard link: https://syzkaller.appspot.com/bug?extid=10007d66ca02b08f0e60 compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1291b1f4a00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=135385a8a00000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+10007d66ca02b08f0e60@syzkaller.appspotmail.com INFO: task syz-executor274:8097 blocked for more than 143 seconds. Not tainted 5.1.0-rc6+ #89 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor274 D28008 8097 8041 0x00000004 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 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 __get_super.part.0+0x203/0x2e0 fs/super.c:788 __get_super include/linux/spinlock.h:329 [inline] get_super+0x2e/0x50 fs/super.c:817 fsync_bdev+0x19/0xd0 fs/block_dev.c:525 invalidate_partition+0x36/0x60 block/genhd.c:1581 drop_partitions block/partition-generic.c:443 [inline] rescan_partitions+0xef/0xa20 block/partition-generic.c:516 __blkdev_reread_part+0x1a2/0x230 block/ioctl.c:173 blkdev_reread_part+0x27/0x40 block/ioctl.c:193 loop_reread_partitions+0x1c/0x40 drivers/block/loop.c:633 loop_set_status+0xe57/0x1380 drivers/block/loop.c:1296 loop_set_status64+0xc2/0x120 drivers/block/loop.c:1416 lo_ioctl+0x8fc/0x2150 drivers/block/loop.c:1559 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x6f2/0x1d10 block/ioctl.c:605 block_ioctl+0xee/0x130 fs/block_dev.c:1933 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x441937 Code: 48 83 c4 08 48 89 d8 5b 5d c3 66 0f 1f 84 00 00 00 00 00 48 89 e8 48 f7 d8 48 39 c3 0f 92 c0 eb 92 66 90 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 8d 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffcabed4e08 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441937 RDX: 00007ffcabed4ea0 RSI: 0000000000004c04 RDI: 0000000000000004 RBP: 0000000000000003 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000000001 R13: 0000000000000004 R14: 0000000000000000 R15: 0000000000000000 INFO: task blkid:8099 blocked for more than 143 seconds. Not tainted 5.1.0-rc6+ #89 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D27504 8099 8021 0x00000004 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 blkdev_put+0x34/0x560 fs/block_dev.c:1866 blkdev_close+0x8b/0xb0 fs/block_dev.c:1915 __fput+0x2e5/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:166 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: 0033:0x7f1ae9c432b0 Code: Bad RIP value. RSP: 002b:00007ffc29ff6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f1ae9c432b0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000028 R09: 0000000001680000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000b9d030 R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005 Showing all locks held in the system: 1 lock held by khungtaskd/1041: #0: 0000000027887009 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5057 1 lock held by rs:main Q:Reg/7921: #0: 00000000e00580d7 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1168 [inline] #0: 00000000e00580d7 (&rq->lock){-.-.}, at: __schedule+0x1f8/0x1cc0 kernel/sched/core.c:3456 1 lock held by rsyslogd/7923: #0: 00000000488dcec4 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8014: #0: 000000001b56f3c3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000da9faa8c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8015: #0: 00000000e00c81bb (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008d689a2e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8016: #0: 00000000177f6359 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000096437898 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8017: #0: 000000002db00e12 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000071f2d88e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8018: #0: 00000000a41b6290 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000c340e26f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8019: #0: 00000000bca104ce (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000007e045212 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8020: #0: 0000000070fdafae (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000b4e26fa9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-executor274/8083: 2 locks held by syz-executor274/8097: #0: 000000007a5ed526 (&bdev->bd_mutex){+.+.}, at: blkdev_reread_part+0x1f/0x40 block/ioctl.c:192 #1: 0000000067606e21 (&type->s_umount_key#39){.+.+}, at: __get_super.part.0+0x203/0x2e0 fs/super.c:788 1 lock held by blkid/8099: #0: 000000007a5ed526 (&bdev->bd_mutex){+.+.}, at: blkdev_put+0x34/0x560 fs/block_dev.c:1866 2 locks held by syz-executor274/11705: #0: 000000002b6bbb34 (&bdev->bd_mutex){+.+.}, at: __blkdev_put+0xbb/0x810 fs/block_dev.c:1833 #1: 00000000bde6230e (loop_ctl_mutex){+.+.}, at: lo_release+0x1f/0x200 drivers/block/loop.c:1755 2 locks held by syz-executor274/11709: #0: 00000000a45cb906 (&bdev->bd_mutex){+.+.}, at: __blkdev_put+0xbb/0x810 fs/block_dev.c:1833 #1: 00000000bde6230e (loop_ctl_mutex){+.+.}, at: lo_release+0x1f/0x200 drivers/block/loop.c:1755 2 locks held by syz-executor274/11716: #0: 00000000a19e2025 (&type->s_umount_key#38/1){+.+.}, at: alloc_super+0x158/0x890 fs/super.c:228 #1: 00000000bde6230e (loop_ctl_mutex){+.+.}, at: lo_simple_ioctl drivers/block/loop.c:1514 [inline] #1: 00000000bde6230e (loop_ctl_mutex){+.+.}, at: lo_ioctl+0x266/0x2150 drivers/block/loop.c:1572 2 locks held by syz-executor274/11717: #0: 00000000e185c083 (&type->s_umount_key#38/1){+.+.}, at: alloc_super+0x158/0x890 fs/super.c:228 #1: 00000000bde6230e (loop_ctl_mutex){+.+.}, at: lo_simple_ioctl drivers/block/loop.c:1514 [inline] #1: 00000000bde6230e (loop_ctl_mutex){+.+.}, at: lo_ioctl+0x266/0x2150 drivers/block/loop.c:1572 2 locks held by blkid/11718: #0: 000000003d9e77b2 (&bdev->bd_mutex){+.+.}, at: __blkdev_put+0xbb/0x810 fs/block_dev.c:1833 #1: 00000000bde6230e (loop_ctl_mutex){+.+.}, at: __loop_clr_fd+0x88/0xd60 drivers/block/loop.c:1046 2 locks held by blkid/11720: #0: 000000000c0297bc (&bdev->bd_mutex){+.+.}, at: __blkdev_put+0xbb/0x810 fs/block_dev.c:1833 #1: 00000000bde6230e (loop_ctl_mutex){+.+.}, at: lo_release+0x1f/0x200 drivers/block/loop.c:1755 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1041 Comm: khungtaskd Not tainted 5.1.0-rc6+ #89 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 0 to CPUs 1: