INFO: task syz-executor.0:2098 blocked for more than 140 seconds.
Not tainted 4.9.189+ #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0 D25016 2098 1 0x00000004
0000000000000083 ffff8801d7fb8000 0000000000000000 ffff8801db621000
ffffffff83031180 ffff8801db621018 ffff8801ab7b7988 ffffffff82818d1e
0000000000000000 ffffffff842a24c8 0000000000000000 ffff8801db6218f0
Call Trace:
[<00000000f2fd406a>] schedule+0x92/0x1c0 kernel/sched/core.c:3546
[<0000000025383f3d>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3579
[<00000000fdd4ecdd>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
[<00000000fdd4ecdd>] mutex_lock_nested+0x38d/0x920 kernel/locking/mutex.c:621
[<000000008c642341>] blkdev_reread_part+0x1f/0x40 block/ioctl.c:189
[<0000000030842547>] loop_reread_partitions+0x7c/0x90 drivers/block/loop.c:637
[<00000000c2354e1b>] loop_clr_fd+0x7dd/0xa60 drivers/block/loop.c:1081
[<00000000a78fa9e1>] lo_ioctl+0x7e9/0x1b10 drivers/block/loop.c:1414
[<000000003f1fe057>] __blkdev_driver_ioctl block/ioctl.c:294 [inline]
[<000000003f1fe057>] blkdev_ioctl+0xe14/0x19e0 block/ioctl.c:590
[<0000000006ec0582>] block_ioctl+0xde/0x120 fs/block_dev.c:1696
[<00000000e868eea6>] vfs_ioctl fs/ioctl.c:43 [inline]
[<00000000e868eea6>] file_ioctl fs/ioctl.c:493 [inline]
[<00000000e868eea6>] do_vfs_ioctl+0xb87/0x11d0 fs/ioctl.c:677
[<00000000aa385531>] SYSC_ioctl fs/ioctl.c:694 [inline]
[<00000000aa385531>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685
[<000000008f552b34>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288
[<00000000b0018c4f>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Showing all locks held in the system:
2 locks held by khungtaskd/24:
#0: (rcu_read_lock){......}, at: [<00000000850e27f1>] check_hung_uninterruptible_tasks kernel/hung_task.c:169 [inline]
#0: (rcu_read_lock){......}, at: [<00000000850e27f1>] watchdog+0x14b/0xaf0 kernel/hung_task.c:263
#1: (tasklist_lock){.+.+..}, at: [<000000007ee69749>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4336
3 locks held by rs:main Q:Reg/1897:
#0: (&f->f_pos_lock){+.+.+.}, at: [<00000000a2bdb3b8>] __fdget_pos+0xa8/0xd0 fs/file.c:782
#1: (sb_writers#4){.+.+.+}, at: [<00000000ec55ac8e>] file_start_write include/linux/fs.h:2646 [inline]
#1: (sb_writers#4){.+.+.+}, at: [<00000000ec55ac8e>] vfs_write+0x3e9/0x520 fs/read_write.c:558
#2: (&sb->s_type->i_mutex_key#9){++++++}, at: [<0000000080ab8f16>] inode_lock include/linux/fs.h:771 [inline]
#2: (&sb->s_type->i_mutex_key#9){++++++}, at: [<0000000080ab8f16>] __generic_file_fsync+0xcd/0x1c0 fs/libfs.c:978
1 lock held by rsyslogd/1899:
#0: (&f->f_pos_lock){+.+.+.}, at: [<00000000a2bdb3b8>] __fdget_pos+0xa8/0xd0 fs/file.c:782
2 locks held by getty/2027:
#0: (&tty->ldisc_sem){++++++}, at: [<0000000014c56b5d>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377
#1: (&ldata->atomic_read_lock){+.+.+.}, at: [<00000000f4b502b9>] n_tty_read+0x1fe/0x1820 drivers/tty/n_tty.c:2156
2 locks held by syz-executor.0/2098:
#0: (&lo->lo_ctl_mutex/1){+.+.+.}, at: [<000000000942adf0>] lo_ioctl+0x8e/0x1b10 drivers/block/loop.c:1404
#1: (&bdev->bd_mutex){+.+.+.}, at: [<000000008c642341>] blkdev_reread_part+0x1f/0x40 block/ioctl.c:189
2 locks held by syz-executor.2/2101:
#0: (&bdev->bd_mutex){+.+.+.}, at: [<00000000456f61c5>] __blkdev_get+0x10e/0xeb0 fs/block_dev.c:1273
#1: (loop_index_mutex){+.+.+.}, at: [<0000000014ec7f0e>] lo_open+0x1d/0xb0 drivers/block/loop.c:1621
2 locks held by syz-executor.1/2109:
#0: (&bdev->bd_mutex){+.+.+.}, at: [<00000000456f61c5>] __blkdev_get+0x10e/0xeb0 fs/block_dev.c:1273
#1: (loop_index_mutex){+.+.+.}, at: [<0000000014ec7f0e>] lo_open+0x1d/0xb0 drivers/block/loop.c:1621
1 lock held by syz-executor.5/19643:
#0: (loop_index_mutex){+.+.+.}, at: [<00000000924ad23b>] loop_control_ioctl+0x7a/0x320 drivers/block/loop.c:1973
1 lock held by syz-executor.4/19642:
#0: (loop_index_mutex){+.+.+.}, at: [<00000000924ad23b>] loop_control_ioctl+0x7a/0x320 drivers/block/loop.c:1973
2 locks held by syz-executor.3/19641:
#0: (loop_index_mutex){+.+.+.}, at: [<00000000924ad23b>] loop_control_ioctl+0x7a/0x320 drivers/block/loop.c:1973
#1: (&lo->lo_ctl_mutex#2){+.+.+.}, at: [<0000000054080c3e>] loop_control_ioctl+0x17f/0x320 drivers/block/loop.c:1987
1 lock held by syz-executor.3/19647:
#0: (loop_index_mutex){+.+.+.}, at: [<00000000924ad23b>] loop_control_ioctl+0x7a/0x320 drivers/block/loop.c:1973
2 locks held by blkid/19646:
#0: (&bdev->bd_mutex){+.+.+.}, at: [<00000000456f61c5>] __blkdev_get+0x10e/0xeb0 fs/block_dev.c:1273
#1: (loop_index_mutex){+.+.+.}, at: [<0000000014ec7f0e>] lo_open+0x1d/0xb0 drivers/block/loop.c:1621
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.189+ #4
ffff8801d98d7cc8 ffffffff81b65c01 0000000000000001 0000000000000000
0000000000000001 ffffffff81099a01 dffffc0000000000 ffff8801d98d7d00
ffffffff81b70e9c 0000000000000001 0000000000000000 0000000000000001
Call Trace:
[<000000004ee8e91d>] __dump_stack lib/dump_stack.c:15 [inline]
[<000000004ee8e91d>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
[<00000000b4e575f2>] nmi_cpu_backtrace.cold+0x47/0x87 lib/nmi_backtrace.c:99
[<0000000084ec061a>] nmi_trigger_cpumask_backtrace+0x124/0x155 lib/nmi_backtrace.c:60
[<00000000de940562>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
[<000000008db43220>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
[<000000008db43220>] check_hung_task kernel/hung_task.c:126 [inline]
[<000000008db43220>] check_hung_uninterruptible_tasks kernel/hung_task.c:183 [inline]
[<000000008db43220>] watchdog+0x670/0xaf0 kernel/hung_task.c:263
[<000000009b2e0d7d>] kthread+0x278/0x310 kernel/kthread.c:211
[<00000000a73a95a0>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:375
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff82827e71