INFO: task syz-executor4:23775 blocked for more than 140 seconds. Not tainted 4.18.0-rc7+ #78 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D23288 23775 4475 0x20020004 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 d_wait_lookup fs/dcache.c:2455 [inline] d_alloc_parallel+0x1448/0x1ea0 fs/dcache.c:2537 __lookup_slow+0x1e6/0x540 fs/namei.c:1613 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 include/linux/namei.h:62 [inline] do_mount+0x17a/0x30e0 fs/namespace.c:2788 __do_compat_sys_mount fs/compat.c:125 [inline] __se_compat_sys_mount fs/compat.c:92 [inline] __ia32_compat_sys_mount+0x5d5/0x860 fs/compat.c:92 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fd3cb9 Code: Bad RIP value. RSP: 002b:00000000f5fcf0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000020000000 RDX: 0000000020000180 RSI: 0000000000000000 RDI: 00000000200005c0 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor4:23788 blocked for more than 140 seconds. Not tainted 4.18.0-rc7+ #78 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D23288 23788 4475 0x20020004 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_compat_sys_newstat+0x8f/0x110 fs/stat.c:626 __se_compat_sys_newstat fs/stat.c:620 [inline] __ia32_compat_sys_newstat+0x52/0x70 fs/stat.c:620 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fd3cb9 Code: Bad RIP value. RSP: 002b:00000000f5f8d0cc EFLAGS: 00000296 ORIG_RAX: 000000000000006a RAX: ffffffffffffffda RBX: 00000000200018c0 RCX: 0000000020001900 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/773: #0: 000000001e3c1b04 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 1 lock held by rsyslogd/4332: #0: 00000000e852d426 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/4423: #0: 000000001735eea8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000004fb6127d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4424: #0: 000000000cdf79c1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000005020321 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4425: #0: 000000006fcf4f2c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000713e439e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4426: #0: 00000000ab9a7489 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000ab6dece0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4427: #0: 000000002e781d36 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000938c9320 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4428: #0: 00000000eb83c63d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000002b1398ae (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4429: #0: 000000008abac742 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000619b03f0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 1 lock held by syz-executor4/23775: #0: 000000005d86477e (&type->i_mutex_dir_key#5){++++}, at: inode_lock_shared include/linux/fs.h:725 [inline] #0: 000000005d86477e (&type->i_mutex_dir_key#5){++++}, at: lookup_slow+0x49/0x80 fs/namei.c:1646 2 locks held by syz-executor4/23788: #0: 000000005d86477e (&type->i_mutex_dir_key#5){++++}, at: inode_lock_shared include/linux/fs.h:725 [inline] #0: 000000005d86477e (&type->i_mutex_dir_key#5){++++}, at: lookup_slow+0x49/0x80 fs/namei.c:1646 #1: 00000000dda6cd1e (&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+ #78 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