INFO: task syz-executor.2:10779 blocked for more than 140 seconds. Not tainted 4.14.114 #4 PF_BRIDGE: br_mdb_parse() with non-bridge "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28976 10779 7240 0x00000004 kobject: 'loop5' (ffff8880a4b00160): kobject_uevent_env Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383 kobject: 'loop5' (ffff8880a4b00160): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop0' (ffff8880a4950e20): kobject_uevent_env schedule+0x92/0x1c0 kernel/sched/core.c:3427 request_wait_answer+0x33e/0x650 fs/fuse/dev.c:474 kobject: 'loop0' (ffff8880a4950e20): fill_kobj_path: path = '/devices/virtual/block/loop0' __fuse_request_send+0x10d/0x1b0 fs/fuse/dev.c:494 kobject: 'loop4' (ffff8880a4aba0e0): kobject_uevent_env fuse_request_send+0x63/0x70 fs/fuse/dev.c:507 kobject: 'loop4' (ffff8880a4aba0e0): fill_kobj_path: path = '/devices/virtual/block/loop4' fuse_simple_request+0x2c4/0x660 fs/fuse/dev.c:565 fuse_removexattr+0x176/0x290 fs/fuse/xattr.c:165 fuse_xattr_set+0x61/0x66 fs/fuse/xattr.c:190 kobject: 'loop5' (ffff8880a4b00160): kobject_uevent_env kobject: 'loop5' (ffff8880a4b00160): fill_kobj_path: path = '/devices/virtual/block/loop5' __vfs_removexattr+0xdf/0x130 fs/xattr.c:379 kobject: 'loop4' (ffff8880a4aba0e0): kobject_uevent_env kobject: 'loop4' (ffff8880a4aba0e0): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop5' (ffff8880a4b00160): kobject_uevent_env vfs_removexattr+0xa3/0x1d0 fs/xattr.c:398 removexattr+0xad/0xf0 fs/xattr.c:693 kobject: 'loop5' (ffff8880a4b00160): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop0' (ffff8880a4950e20): kobject_uevent_env kobject: 'loop0' (ffff8880a4950e20): fill_kobj_path: path = '/devices/virtual/block/loop0' path_removexattr+0xfd/0x110 fs/xattr.c:707 SYSC_lremovexattr fs/xattr.c:727 [inline] SyS_lremovexattr+0x20/0x30 fs/xattr.c:724 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x458da9 RSP: 002b:00007fd27c918c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000c6 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000458da9 RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000020000240 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd27c9196d4 R13: 00000000004c4bb2 R14: 00000000004d8600 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1008: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4541 1 lock held by rsyslogd/7070: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0xab/0xd0 fs/file.c:769 2 locks held by getty/7193: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7194: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7195: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7196: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7197: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7198: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7199: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.2/10779: #0: (sb_writers#17){.+.+}, at: [] sb_start_write include/linux/fs.h:1545 [inline] #0: (sb_writers#17){.+.+}, at: [] mnt_want_write+0x3f/0xb0 fs/namespace.c:386 #1: (&type->i_mutex_dir_key#7){+.+.}, at: [] inode_lock include/linux/fs.h:715 [inline] #1: (&type->i_mutex_dir_key#7){+.+.}, at: [] vfs_removexattr+0x81/0x1d0 fs/xattr.c:393 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1008 Comm: khungtaskd Not tainted 4.14.114 #4 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x138/0x19c lib/dump_stack.c:53 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x141/0x189 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:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5e7/0xb90 kernel/hung_task.c:274 kthread+0x31c/0x430 kernel/kthread.c:232 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 60 Comm: kworker/u4:2 Not tainted 4.14.114 #4 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker task: ffff8880a9806080 task.stack: ffff8880a9808000 RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:773 [inline] RIP: 0010:__lock_acquire+0x885/0x45e0 kernel/locking/lockdep.c:3362 RSP: 0018:ffff8880a980fab0 EFLAGS: 00000046 RAX: 1ffffffff0ee296c RBX: 0000000000000000 RCX: 0000000000000002 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff8778ef60 RBP: ffff8880a980fc60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffff8880a9806080 R12: ffffffff8778ef60 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000073c000 CR3: 00000000678f2000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3991 rcu_lock_acquire include/linux/rcupdate.h:244 [inline] rcu_read_lock include/linux/rcupdate.h:631 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:416 [inline] batadv_nc_worker+0x107/0x6d0 net/batman-adv/network-coding.c:726 process_one_work+0x868/0x1610 kernel/workqueue.c:2114 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248 kthread+0x31c/0x430 kernel/kthread.c:232 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402 Code: 00 0f 86 0e f9 ff ff 89 05 99 9f 3f 07 e9 03 f9 ff ff 48 c7 c0 60 4b 71 87 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 <0f> 85 01 2b 00 00 48 83 3d 2d 58 29 06 00 0f 84 fb 08 00 00 9c