kworker/u4:1(21): getblk(): executed=9 bh_count=0 bh_state=0 kworker/u4:1(21): getblk(): executed=9 bh_count=0 bh_state=0 kworker/u4:1(21): getblk(): executed=9 bh_count=0 bh_state=0 kworker/u4:1(21): getblk(): executed=9 bh_count=0 bh_state=0 kworker/u4:1(21): getblk(): executed=9 bh_count=0 bh_state=0 INFO: task syz-executor0:5690 blocked for more than 140 seconds. Not tainted 4.19.0-next-20181102+ #104 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D16296 5690 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 __rwsem_down_write_failed_common+0xc9a/0x15e0 kernel/locking/rwsem-xadd.c:577 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:606 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0xa5/0x130 kernel/locking/rwsem.c:72 deactivate_super+0x2b3/0x320 fs/super.c:358 cleanup_mnt+0xbf/0x160 fs/namespace.c:1049 __cleanup_mnt+0x16/0x20 fs/namespace.c:1056 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x318/0x380 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+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459fb7 Code: Bad RIP value. RSP: 002b:00007ffd2f1d7c18 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000459fb7 RDX: 0000000000402e70 RSI: 0000000000000002 RDI: 00007ffd2f1d7cc0 RBP: 0000000000000a8c R08: 0000000000000000 R09: 000000000000000b R10: 0000000000000005 R11: 0000000000000202 R12: 00007ffd2f1d8d50 R13: 0000000000e9e940 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 3 locks held by kworker/u4:1/21: 1 lock held by khungtaskd/1009: #0: 000000002f9e2a61 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 1 lock held by rsyslogd/5562: #0: 0000000043cf06c6 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5652: #0: 00000000417fba8f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000008ca3be5e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5653: #0: 00000000c8a80aba (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000c1eceb48 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5654: #0: 00000000ab6b075e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000047fef53a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5655: #0: 0000000092b85509 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000008f90e343 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5656: #0: 00000000a5517517 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000002724baf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5657: #0: 00000000876fd2e7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000bf8a668e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5658: #0: 00000000c7665e82 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000003d50a76b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 1 lock held by syz-executor0/5690: #0: 00000000e6618c14 (&fc->fs_type->s_umount_key#64){++++}, at: deactivate_super+0x2b3/0x320 fs/super.c:358 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1009 Comm: khungtaskd Not tainted 4.19.0-next-20181102+ #104 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+0x244/0x39d lib/dump_stack.c:113 nmi_cpu_backtrace.cold.2+0x5c/0xa1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1e8/0x22a 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:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xb4c/0x1060 kernel/hung_task.c:289 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.658 msecs NMI backtrace for cpu 0 CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 4.19.0-next-20181102+ #104 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:match_held_lock+0x2f0/0x8d0 kernel/locking/lockdep.c:3401 Code: 00 00 00 fc ff df c6 04 08 f8 75 4a 31 c0 48 ba 00 00 00 00 00 fc ff df 48 01 d3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 <48> 8b 75 d0 65 48 33 34 25 28 00 00 00 0f 85 c3 02 00 00 48 81 c4 RSP: 0018:ffff8801d942d960 EFLAGS: 00000082 RAX: 0000000000000000 RBX: ffffed003b285b31 RCX: ffffffff819d24ec RDX: dffffc0000000000 RSI: ffff88013bd1b7b8 RDI: ffff8801d941ee72 RBP: ffff8801d942da50 R08: ffff8801d941e580 R09: ffffed003b285b6a R10: ffffed003b285b6a R11: 0000000000000003 R12: ffff8801d941e580 R13: ffff8801d941ee50 R14: ffff8801d942da28 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001d9010000 CR4: 00000000001406f0 DR0: 00000000200001c0 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: __lock_is_held+0xb5/0x140 kernel/locking/lockdep.c:3664 lock_is_held_type+0x118/0x210 kernel/locking/lockdep.c:3882 lock_is_held include/linux/lockdep.h:339 [inline] xa_entry include/linux/xarray.h:709 [inline] xas_reload include/linux/xarray.h:1057 [inline] find_get_entry+0xc7e/0x1120 mm/filemap.c:1440 pagecache_get_page+0x12f/0xf00 mm/filemap.c:1518 find_get_page_flags include/linux/pagemap.h:278 [inline] __find_get_block_slow fs/buffer.c:205 [inline] __find_get_block+0x635/0xf10 fs/buffer.c:1325 __getblk_slow fs/buffer.c:1058 [inline] __getblk_gfp+0x3d3/0x1030 fs/buffer.c:1351 __bread_gfp+0x2d/0x310 fs/buffer.c:1385 sb_bread include/linux/buffer_head.h:307 [inline] __fat_write_inode+0x347/0xb60 fs/fat/inode.c:860 fat_write_inode+0x97/0x180 fs/fat/inode.c:909 write_inode fs/fs-writeback.c:1176 [inline] __writeback_single_inode+0xf4a/0x1650 fs/fs-writeback.c:1375 writeback_sb_inodes+0x71f/0x1210 fs/fs-writeback.c:1580 __writeback_inodes_wb+0x1b9/0x340 fs/fs-writeback.c:1649 wb_writeback+0xa64/0xfb0 fs/fs-writeback.c:1758 wb_check_old_data_flush fs/fs-writeback.c:1860 [inline] wb_do_writeback fs/fs-writeback.c:1913 [inline] wb_workfn+0xffe/0x1780 fs/fs-writeback.c:1942 process_one_work+0xc8b/0x1c40 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352