INFO: task syz-executor:5848 blocked for more than 143 seconds. Not tainted 6.16.0-rc1-syzkaller-00236-g8c6bc74c7f89 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21960 pid:5848 tgid:5848 ppid:1 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 __bch2_fs_stop+0x704/0x900 fs/bcachefs/super.c:697 generic_shutdown_super+0x135/0x2c0 fs/super.c:643 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2618 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff3e458fc57 RSP: 002b:00007ffec4d0e398 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007ff3e458fc57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffec4d0e450 RBP: 00007ffec4d0e450 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffec4d0f4e0 R13: 00007ff3e4610925 R14: 0000000000030fc0 R15: 00007ffec4d0f520 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13ed60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13ed60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13ed60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 3 locks held by kworker/1:1/43: #0: ffff88801a478d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a478d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc90000b37bc0 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000b37bc0 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8e144878 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #2: ffffffff8e144878 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998 2 locks held by getty/5588: #0: ffff88814c0c70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fee2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5848: #0: ffff88807bafa0e0 (&type->s_umount_key#112){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88807bafa0e0 (&type->s_umount_key#112){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88807bafa0e0 (&type->s_umount_key#112){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 1 lock held by syz-executor/8588: 1 lock held by syz.6.1216/9640: #0: ffff88807bafa0e0 (&type->s_umount_key#112){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88807bafa0e0 (&type->s_umount_key#112){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz-executor/9942: 3 locks held by kworker/0:10/10378: 1 lock held by syz-executor/11136: #0: ffffffff8e144878 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8e144878 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998 1 lock held by syz.0.1676/11168: 1 lock held by syz.4.1674/11169: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc1-syzkaller-00236-g8c6bc74c7f89 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 3485 Comm: kworker/u8:6 Not tainted 6.16.0-rc1-syzkaller-00236-g8c6bc74c7f89 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:insn_get_opcode+0xe0/0xf30 arch/x86/lib/insn.c:287 Code: 49 8d 6e 60 48 89 e8 48 c1 e8 03 48 89 84 24 88 00 00 00 80 3c 18 00 74 08 48 89 ef e8 d9 2f be f6 48 89 6c 24 48 4c 3b 6d 00 <0f> 87 b0 0a 00 00 4c 89 f8 48 c1 e8 03 0f b6 04 18 84 c0 0f 85 c4 RSP: 0018:ffffc9000bfb7540 EFLAGS: 00000283 RAX: 1ffff920017f6f08 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff888030f91e00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000bfb7840 R08: ffff888030f91e00 R09: 0000000000000002 R10: 0000000000000010 R11: 0000000000000000 R12: ffffc9000bfb77fc R13: ffffffff8b85604b R14: ffffc9000bfb77e0 R15: ffffffff8b85604a FS: 0000000000000000(0000) GS:ffff888125d51000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000017038 CR3: 000000000df38000 CR4: 0000000000350ef0 Call Trace: insn_get_modrm+0x64/0x750 arch/x86/lib/insn.c:375 insn_get_sib arch/x86/lib/insn.c:449 [inline] insn_get_displacement+0x155/0x9f0 arch/x86/lib/insn.c:490 insn_get_immediate+0x64/0x1280 arch/x86/lib/insn.c:656 insn_get_length arch/x86/lib/insn.c:728 [inline] insn_decode+0x30e/0x4f0 arch/x86/lib/insn.c:767 __smp_text_poke_batch_add+0x1af/0x8c0 arch/x86/kernel/alternative.c:2990 arch_jump_label_transform_queue+0x8b/0x110 arch/x86/kernel/jump_label.c:138 __jump_label_update+0x185/0x3a0 kernel/jump_label.c:513 static_key_disable_cpuslocked+0xc5/0x1b0 kernel/jump_label.c:240 static_key_disable+0x1a/0x20 kernel/jump_label.c:248 toggle_allocation_gate+0x1a1/0x240 mm/kfence/core.c:855 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245