INFO: task syz-executor5:8879 blocked for more than 140 seconds. Not tainted 4.19.0-rc7+ #57 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor5 D25552 8879 5494 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 __rwsem_down_write_failed_common+0xbb9/0x1670 kernel/locking/rwsem-xadd.c:566 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:595 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 inode_lock include/linux/fs.h:738 [inline] utimes_common.isra.1+0x45c/0x8e0 fs/utimes.c:90 do_utimes+0x1f7/0x380 fs/utimes.c:156 __do_sys_utime fs/utimes.c:35 [inline] __se_sys_utime fs/utimes.c:24 [inline] __x64_sys_utime+0x1df/0x290 fs/utimes.c:24 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: 83 c4 18 c3 e8 d8 64 00 00 48 8b 04 24 48 8b 4c 24 08 48 89 01 e8 d7 2d fc ff e8 22 7a fc ff b8 02 00 00 00 48 8d 0d 6a 60 09 <01> 87 01 8b 05 62 60 09 01 83 f8 01 0f 85 8a 00 00 00 b8 01 00 00 RSP: 002b:00007f32ffc44c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000084 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000020000040 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f32ffc456d4 R13: 00000000004c4f36 R14: 00000000004d84d8 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/981: #0: 0000000037dfd5ee (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4435 2 locks held by kworker/0:2/2495: #0: 00000000508168f8 ((wq_completion)"events"){+.+.}, at: __write_once_size include/linux/compiler.h:215 [inline] #0: 00000000508168f8 ((wq_completion)"events"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000508168f8 ((wq_completion)"events"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 00000000508168f8 ((wq_completion)"events"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 00000000508168f8 ((wq_completion)"events"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 00000000508168f8 ((wq_completion)"events"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 00000000508168f8 ((wq_completion)"events"){+.+.}, at: process_one_work+0xb43/0x1b90 kernel/workqueue.c:2124 #1: 00000000103300b2 ((work_completion)(&m->rq)){+.+.}, at: process_one_work+0xb9a/0x1b90 kernel/workqueue.c:2128 1 lock held by rsyslogd/5225: #0: 000000000589aa89 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5315: #0: 0000000000c859a6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000008be3c552 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5316: #0: 0000000069e52f7c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000e244a037 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5317: #0: 00000000a917a262 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000b6f79584 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5318: #0: 000000009d9b6f8e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000acdac465 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5319: #0: 000000004a48b466 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000009553b9c0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5320: #0: 000000000c02c522 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000c013910d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5321: #0: 0000000008da2669 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000e2aa2896 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-executor5/8862: #0: 0000000029e5ce59 (sb_writers#21){.+.+}, at: sb_start_write include/linux/fs.h:1566 [inline] #0: 0000000029e5ce59 (sb_writers#21){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 #1: 00000000acab96cc (&sb->s_type->i_mutex_key#25){++++}, at: inode_lock include/linux/fs.h:738 [inline] #1: 00000000acab96cc (&sb->s_type->i_mutex_key#25){++++}, at: utimes_common.isra.1+0x45c/0x8e0 fs/utimes.c:90 2 locks held by syz-executor5/8879: #0: 0000000029e5ce59 (sb_writers#21){.+.+}, at: sb_start_write include/linux/fs.h:1566 [inline] #0: 0000000029e5ce59 (sb_writers#21){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 #1: 00000000acab96cc (&sb->s_type->i_mutex_key#25){++++}, at: inode_lock include/linux/fs.h:738 [inline] #1: 00000000acab96cc (&sb->s_type->i_mutex_key#25){++++}, at: utimes_common.isra.1+0x45c/0x8e0 fs/utimes.c:90 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 981 Comm: khungtaskd Not tainted 4.19.0-rc7+ #57 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+0x1c4/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed 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:204 [inline] watchdog+0xb3e/0x1050 kernel/hung_task.c:265 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57