INFO: task syz-executor.2:17319 blocked for more than 143 seconds. Not tainted 6.6.0-syzkaller-16201-gb57b17e88bf5 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:26376 pid:17319 tgid:17300 ppid:5103 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0x1960/0x4a80 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0x149/0x260 kernel/sched/core.c:6778 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6835 rwsem_down_write_slowpath+0xee6/0x13a0 kernel/locking/rwsem.c:1178 __down_write_common+0x1aa/0x200 kernel/locking/rwsem.c:1306 inode_lock include/linux/fs.h:802 [inline] do_lock_mount+0x112/0x390 fs/namespace.c:2456 lock_mount fs/namespace.c:2498 [inline] do_new_mount_fc fs/namespace.c:3280 [inline] do_new_mount+0x3fc/0xae0 fs/namespace.c:3339 do_mount fs/namespace.c:3677 [inline] __do_sys_mount fs/namespace.c:3886 [inline] __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3863 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7fc71d27cae9 RSP: 002b:00007fc71df0e0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fc71d39c050 RCX: 00007fc71d27cae9 RDX: 0000000020002100 RSI: 00000000200020c0 RDI: 0000000000000000 RBP: 00007fc71d2c847a R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007fc71d39c050 R15: 00007ffdd514ff88 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d92d0a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8d92d0a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8d92d0a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6613 2 locks held by getty/4812: #0: ffff88802a7720a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 1 lock held by syz-executor.4/5099: #0: ffffffff8d932a78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:293 [inline] #0: ffffffff8d932a78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a3/0x890 kernel/rcu/tree_exp.h:996 1 lock held by syz-executor.3/5101: #0: ffffffff8d932a78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #0: ffffffff8d932a78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x46c/0x890 kernel/rcu/tree_exp.h:996 2 locks held by kworker/1:4/5144: #0: ffff888012c72938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #0: ffff888012c72938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1400 kernel/workqueue.c:2703 #1: ffffc9000495fd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #1: ffffc9000495fd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1400 kernel/workqueue.c:2703 3 locks held by syz-executor.2/17302: 1 lock held by syz-executor.2/17319: #0: ffff888038423d30 (&sb->s_type->i_mutex_key#30){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #0: ffff888038423d30 (&sb->s_type->i_mutex_key#30){++++}-{3:3}, at: do_lock_mount+0x112/0x390 fs/namespace.c:2456 3 locks held by syz-executor.0/17391: 1 lock held by syz-executor.0/17398: #0: ffff8880384243b0 (&sb->s_type->i_mutex_key#30){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #0: ffff8880384243b0 (&sb->s_type->i_mutex_key#30){++++}-{3:3}, at: do_lock_mount+0x112/0x390 fs/namespace.c:2456 1 lock held by udevd/17487: #0: ffff8880b983c358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 4 locks held by kworker/1:1/17518: 5 locks held by syz-executor.2/18528: 2 locks held by syz-executor.2/18538: 2 locks held by syz-executor.5/18531: 1 lock held by syz-executor.5/18537: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.6.0-syzkaller-16201-gb57b17e88bf5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x498/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x310 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfa9/0xff0 kernel/hung_task.c:379 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 2393 Comm: kworker/u4:7 Not tainted 6.6.0-syzkaller-16201-gb57b17e88bf5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Workqueue: bat_events batadv_nc_worker RIP: 0010:lock_release+0x15/0x9d0 kernel/locking/lockdep.c:5761 Code: ff ff 89 c6 48 c7 c7 20 aa 7f 8d e8 a5 69 50 03 e9 00 fc ff ff f3 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 <48> 81 ec 00 01 00 00 49 89 f5 48 89 7c 24 20 65 48 8b 04 25 28 00 RSP: 0018:ffffc9000984faa0 EFLAGS: 00000286 RAX: ffffffff8ae9150f RBX: ffff88803f2c0b80 RCX: ffff8880253b0000 RDX: 0000000000000000 RSI: ffffffff8ae91519 RDI: ffff88803f2c0b98 RBP: ffffc9000984fad8 R08: 0000000000000003 R09: fffff52001309f50 R10: dffffc0000000000 R11: fffff52001309f50 R12: ffff88802a694c80 R13: dffffc0000000000 R14: ffffffff8ae91519 R15: ffff888020d056d0 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110f292ebf CR3: 000000000d730000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:165 [inline] _raw_spin_unlock_bh+0x1b/0x40 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x309/0x3a0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x365/0x610 net/batman-adv/network-coding.c:722 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x90f/0x1400 kernel/workqueue.c:2703 worker_thread+0xa5f/0xff0 kernel/workqueue.c:2784 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242