INFO: task syz-executor2:448 blocked for more than 140 seconds. Not tainted 4.18.0-rc7+ #169 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D23352 448 4428 0x00000004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_write_failed_common+0x95d/0x1630 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+0xaa/0x130 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:715 [inline] fuse_reverse_inval_entry+0xae/0x6d0 fs/fuse/dir.c:969 fuse_notify_inval_entry fs/fuse/dev.c:1491 [inline] fuse_notify fs/fuse/dev.c:1764 [inline] fuse_dev_do_write+0x2b97/0x3700 fs/fuse/dev.c:1848 fuse_dev_write+0x19a/0x240 fs/fuse/dev.c:1928 call_write_iter include/linux/fs.h:1793 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x6c6/0x9f0 fs/read_write.c:487 vfs_write+0x1f8/0x560 fs/read_write.c:549 ksys_write+0x101/0x260 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x456a09 Code: 24 00 00 00 e8 e8 4e fd ff 0f 0b e8 c1 34 00 00 e9 3c ff ff ff cc cc cc cc cc cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff <48> 3b 61 10 76 40 48 83 ec 28 48 89 6c 24 20 48 8d 6c 24 20 48 8b RSP: 002b:00007f4d7ab97c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f4d7ab986d4 RCX: 0000000000456a09 RDX: 000000000000002b RSI: 0000000020000540 RDI: 0000000000000013 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d5ed8 R14: 00000000004c94cb R15: 0000000000000000 INFO: task syz-executor2:451 blocked for more than 140 seconds. Not tainted 4.18.0-rc7+ #169 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D24280 451 4428 0x00000004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 request_wait_answer+0x4c8/0x920 fs/fuse/dev.c:463 __fuse_request_send+0x12a/0x1d0 fs/fuse/dev.c:483 fuse_request_send+0x62/0xa0 fs/fuse/dev.c:496 fuse_simple_request+0x33d/0x730 fs/fuse/dev.c:554 fuse_lookup_name+0x3ee/0x830 fs/fuse/dir.c:323 fuse_lookup+0xf9/0x4c0 fs/fuse/dir.c:360 __lookup_slow+0x2b5/0x540 fs/namei.c:1630 lookup_slow+0x57/0x80 fs/namei.c:1647 walk_component+0x94a/0x2630 fs/namei.c:1769 lookup_last fs/namei.c:2237 [inline] path_lookupat.isra.45+0x202/0xbf0 fs/namei.c:2287 filename_lookup+0x264/0x510 fs/namei.c:2321 user_path_at_empty+0x40/0x50 fs/namei.c:2584 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0x129/0x210 fs/stat.c:185 vfs_stat include/linux/fs.h:3102 [inline] __do_sys_newstat+0x8f/0x110 fs/stat.c:337 __se_sys_newstat fs/stat.c:333 [inline] __x64_sys_newstat+0x54/0x80 fs/stat.c:333 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x456a09 Code: 24 00 00 00 e8 e8 4e fd ff 0f 0b e8 c1 34 00 00 e9 3c ff ff ff cc cc cc cc cc cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff <48> 3b 61 10 76 40 48 83 ec 28 48 89 6c 24 20 48 8d 6c 24 20 48 8b RSP: 002b:00007f4d7ab76c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 00007f4d7ab776d4 RCX: 0000000000456a09 RDX: 0000000000000000 RSI: 0000000020000380 RDI: 0000000020000340 RBP: 0000000000930140 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d52a8 R14: 00000000004db57b R15: 0000000000000001 Showing all locks held in the system: 1 lock held by khungtaskd/773: #0: 0000000006cb46f0 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 2 locks held by rsyslogd/4286: #0: 000000003664efcb (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 #1: 00000000f2c299f1 (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:9830 [inline] #1: 00000000f2c299f1 (&rq->lock){-.-.}, at: pick_next_task_fair+0x1018/0x17a0 kernel/sched/fair.c:7017 2 locks held by getty/4376: #0: 0000000029b56f8c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000095b2260f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4377: #0: 00000000946f0d60 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000e5110bbb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4378: #0: 000000006f2bf901 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000006bb68dd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4379: #0: 00000000b5cf125a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000fdad7a56 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4380: #0: 00000000a6c3d66a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000eae53515 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4381: #0: 00000000851468aa (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000b243ac8f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4382: #0: 00000000379d7c93 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000930e8d5d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-executor2/448: #0: 0000000074676920 (&fc->killsb){++++}, at: fuse_notify_inval_entry fs/fuse/dev.c:1488 [inline] #0: 0000000074676920 (&fc->killsb){++++}, at: fuse_notify fs/fuse/dev.c:1764 [inline] #0: 0000000074676920 (&fc->killsb){++++}, at: fuse_dev_do_write+0x2b2d/0x3700 fs/fuse/dev.c:1848 #1: 000000004ad21cd0 (&type->i_mutex_dir_key#5){++++}, at: inode_lock include/linux/fs.h:715 [inline] #1: 000000004ad21cd0 (&type->i_mutex_dir_key#5){++++}, at: fuse_reverse_inval_entry+0xae/0x6d0 fs/fuse/dir.c:969 2 locks held by syz-executor2/451: #0: 000000004ad21cd0 (&type->i_mutex_dir_key#5){++++}, at: inode_lock_shared include/linux/fs.h:725 [inline] #0: 000000004ad21cd0 (&type->i_mutex_dir_key#5){++++}, at: lookup_slow+0x49/0x80 fs/namei.c:1646 #1: 0000000069b072ed (&fi->mutex){+.+.}, at: fuse_lock_inode+0xaf/0xe0 fs/fuse/inode.c:363 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 773 Comm: khungtaskd Not tainted 4.18.0-rc7+ #169 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+0x1c9/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x151/0x192 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:138 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline] watchdog+0x9c4/0xf80 kernel/hung_task.c:252 kthread+0x345/0x410 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54