INFO: task syz-executor0:14830 blocked for more than 140 seconds. Not tainted 4.19.0-rc7+ #282 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D23928 14830 10203 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 request_wait_answer+0x4a6/0x900 fs/fuse/dev.c:474 __fuse_request_send+0x12a/0x1d0 fs/fuse/dev.c:494 fuse_request_send+0x62/0xa0 fs/fuse/dev.c:507 fuse_simple_request+0x33d/0x730 fs/fuse/dev.c:565 fuse_lookup_name+0x3ee/0x830 fs/fuse/dir.c:323 fuse_lookup+0xff/0x4c0 fs/fuse/dir.c:361 __lookup_slow+0x2b5/0x540 fs/namei.c:1671 lookup_slow+0x57/0x80 fs/namei.c:1688 walk_component+0x92b/0x25c0 fs/namei.c:1810 lookup_last fs/namei.c:2273 [inline] path_lookupat.isra.43+0x212/0xc00 fs/namei.c:2318 filename_lookup+0x26a/0x520 fs/namei.c:2348 user_path_at_empty+0x40/0x50 fs/namei.c:2608 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0x129/0x210 fs/stat.c:185 vfs_stat include/linux/fs.h:3113 [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: 0033:0x457569 Code: Bad RIP value. RSP: 002b:00007f5d67d78c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000020000480 RDI: 00000000200000c0 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5d67d796d4 R13: 00000000004ddf3b R14: 00000000004d7a58 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/982: #0: 00000000b1b099ee (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4435 2 locks held by udevd/3194: 1 lock held by rsyslogd/5213: #0: 0000000066e73e29 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5303: #0: 000000006b3a280e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000022498eef (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5304: #0: 00000000cc8ba0fd (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000009351f81a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5305: #0: 000000007eaa0741 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000dee88e54 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5306: #0: 00000000aaf87176 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000091abdeff (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5307: #0: 000000004c7e2a55 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000715a6534 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5308: #0: 000000003c6c085d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000002c21eb5f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5309: #0: 000000000bd8ec20 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000001c6d221f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-executor0/14830: #0: 00000000625aca6c (&type->i_mutex_dir_key#9){++++}, at: inode_lock_shared include/linux/fs.h:748 [inline] #0: 00000000625aca6c (&type->i_mutex_dir_key#9){++++}, at: lookup_slow+0x49/0x80 fs/namei.c:1687 #1: 00000000c54d5141 (&fi->mutex){+.+.}, at: fuse_lock_inode+0xba/0xf0 fs/fuse/inode.c:365 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 982 Comm: khungtaskd Not tainted 4.19.0-rc7+ #282 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: INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.267 msecs NMI backtrace for cpu 0 CPU: 0 PID: 3194 Comm: udevd Not tainted 4.19.0-rc7+ #282 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:arch_local_irq_disable arch/x86/include/asm/paravirt.h:793 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:806 [inline] RIP: 0010:lock_is_held_type+0xc3/0x210 kernel/locking/lockdep.c:3934 Code: 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 42 01 00 00 48 83 3d 14 18 d2 07 00 0f 84 f2 00 00 00 fa <66> 0f 1f 44 00 00 65 4c 8b 24 25 40 ee 01 00 49 8d bc 24 7c 08 00 RSP: 0018:ffff8801c82f71a0 EFLAGS: 00000082 RAX: dffffc0000000000 RBX: 0000000000000282 RCX: 0000000000000000 RDX: 1ffffffff1263e42 RSI: 00000000ffffffff RDI: ffffffff8931f210 RBP: ffff8801c82f71c0 R08: ffffffff81e466ed R09: 0000000000000000 R10: ffff8801c82f7658 R11: 0000000000000000 R12: 1ffff1003905ee3b R13: ffffffff8939a760 R14: ffffffff880b1760 R15: 000000000000038c FS: 00007ff0986e27a0(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001c8686000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:344 [inline] ___might_sleep+0x24d/0x300 kernel/sched/core.c:6108 __might_sleep+0x95/0x190 kernel/sched/core.c:6096 __mutex_lock_common kernel/locking/mutex.c:908 [inline] __mutex_lock+0x138/0x1700 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 ep_scan_ready_list+0xd2d/0x1050 fs/eventpoll.c:690 ep_send_events fs/eventpoll.c:1713 [inline] ep_poll+0x572/0x13d0 fs/eventpoll.c:1840 do_epoll_wait+0x1b0/0x200 fs/eventpoll.c:2198 __do_sys_epoll_wait fs/eventpoll.c:2208 [inline] __se_sys_epoll_wait fs/eventpoll.c:2205 [inline] __x64_sys_epoll_wait+0x97/0xf0 fs/eventpoll.c:2205 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7ff097df6943 Code: 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 90 90 90 90 90 90 83 3d b5 dc 2a 00 00 75 13 49 89 ca b8 e8 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 3b c4 00 00 48 89 04 24 RSP: 002b:00007fff5d2db9b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: ffffffffffffffda RBX: 0000000000000bb8 RCX: 00007ff097df6943 RDX: 0000000000000008 RSI: 00007fff5d2dbab0 RDI: 000000000000000a RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000bb8 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 0000000000c1a6d0 R15: 0000000000c01250