INFO: task syz-executor181:9127 blocked for more than 143 seconds. Not tainted 5.2.0-rc7 #39 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor181 D28528 9127 9124 0x00004004 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 schedule_timeout+0x717/0xc50 kernel/time/timer.c:1783 io_schedule_timeout+0x26/0x80 kernel/sched/core.c:5119 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common_io kernel/sched/completion.c:121 [inline] wait_for_completion_io+0x29c/0x440 kernel/sched/completion.c:169 submit_bio_wait+0x11d/0x1c0 block/bio.c:1003 blkdev_issue_flush+0x20d/0x300 block/blk-flush.c:449 blkdev_fsync+0x95/0xd0 fs/block_dev.c:687 vfs_fsync_range+0x141/0x230 fs/sync.c:197 vfs_fsync fs/sync.c:211 [inline] do_fsync+0x54/0xa0 fs/sync.c:221 __do_sys_fdatasync fs/sync.c:234 [inline] __se_sys_fdatasync fs/sync.c:232 [inline] __x64_sys_fdatasync+0x36/0x50 fs/sync.c:232 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x449ee9 Code: Bad RIP value. RSP: 002b:00007f9585dc5ce8 EFLAGS: 00000246 ORIG_RAX: 000000000000004b RAX: ffffffffffffffda RBX: 00000000006dbc58 RCX: 0000000000449ee9 RDX: 0000000000449ee9 RSI: 0000000000000000 RDI: 0000000000000009 RBP: 00000000006dbc50 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc5c R13: 00007ffdff9c94cf R14: 00007f9585dc69c0 R15: 000000000000002d Showing all locks held in the system: 1 lock held by khungtaskd/1042: #0: 00000000157a165b (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5149 1 lock held by rsyslogd/8974: #0: 00000000b79d448d (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/9096: #0: 00000000828483d0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000056df9ec9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9097: #0: 00000000d2c80559 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000f827a46b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9098: #0: 0000000059cdb01f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000068caf1a6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9099: #0: 00000000c35eb1b4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000030d85cd9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9100: #0: 0000000027e907f0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000540edcb4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9101: #0: 000000004f6f958d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000956fe3e2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9102: #0: 000000003d70fbd4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000f02db2a4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1042 Comm: khungtaskd Not tainted 5.2.0-rc7 #39 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:205 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:289 kthread+0x354/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60