INFO: task syz.0.2625:13687 blocked for more than 156 seconds. Not tainted 6.12.0-rc7-syzkaller-01770-gdd7207838d38 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2625 state:D stack:23808 pid:13687 tgid:13687 ppid:5845 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6693 __schedule_loop kernel/sched/core.c:6770 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6785 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6842 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 pipe_release+0x48/0x320 fs/pipe.c:727 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f204257e819 RSP: 002b:00007ffd27666298 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f2042737ba0 RCX: 00007f204257e819 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f2042737ba0 R08: 0000000000000544 R09: 00007ffd2766658f R10: 00007f2042737ac0 R11: 0000000000000246 R12: 0000000000062d81 R13: 00007f2042736240 R14: 0000000000000032 R15: ffffffffffffffff Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 2 locks held by kworker/u8:2/35: 2 locks held by kworker/u8:3/52: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000bc7d00 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000bc7d00 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 2 locks held by getty/5596: #0: ffff8880318b30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fc62f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5837: 2 locks held by syz-executor/5839: 1 lock held by syz-executor/5841: 2 locks held by syz-executor/5842: 2 locks held by syz-executor/5848: 2 locks held by syz-executor/13675: 1 lock held by syz.0.2625/13687: #0: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc7-syzkaller-01770-gdd7207838d38 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 3569 Comm: kworker/u8:10 Not tainted 6.12.0-rc7-syzkaller-01770-gdd7207838d38 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:lockdep_hardirqs_on_prepare+0x1e1/0x780 Code: 4c 89 7c 24 18 48 8b 44 24 10 4c 8b b0 d0 0a 00 00 48 8d b8 b8 0a 00 00 48 89 f8 48 c1 e8 03 80 3c 10 00 74 05 e8 8f a8 8e 00 <48> 8b 5c 24 10 4c 89 b3 b8 0a 00 00 48 c7 c7 a0 d7 0a 8c e8 a7 09 RSP: 0018:ffffc9000cd2f940 EFLAGS: 00000046 RAX: 1ffff11006500157 RBX: 1ffff920019a5f30 RCX: ffffffff9a3ec903 RDX: dffffc0000000000 RSI: ffffffff8c610dc0 RDI: ffff888032800ab8 RBP: ffffc9000cd2f9e8 R08: ffffffff901d742f R09: 1ffffffff203ae85 R10: dffffc0000000000 R11: fffffbfff203ae86 R12: dffffc0000000000 R13: 1ffff920019a5f48 R14: 0ea80f939c3996f9 R15: 1ffff920019a5f2c FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe7ec667d60 CR3: 000000000e734000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_hardirqs_on+0x28/0x40 kernel/trace/trace_preemptirq.c:61 __local_bh_enable_ip+0x168/0x200 kernel/softirq.c:387 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x312/0x3b0 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:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244