INFO: task syz-executor:6424 blocked for more than 143 seconds. Not tainted 6.15.0-rc5-syzkaller-00300-g3ce9925823c7 #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:23656 pid:6424 tgid:6424 ppid:1 task_flags:0x40054c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:116 __flush_work+0x7d7/0xcc0 kernel/workqueue.c:4244 __cancel_work_sync+0x10c/0x130 kernel/workqueue.c:4364 hci_cmd_sync_clear+0x33/0x100 net/bluetooth/hci_sync.c:655 hci_unregister_dev+0x1b8/0x620 net/bluetooth/hci_core.c:2674 vhci_release+0x79/0xf0 drivers/bluetooth/hci_vhci.c:665 __fput+0x3ff/0xb70 fs/file_table.c:465 task_work_run+0x14d/0x240 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xafb/0x2c30 kernel/exit.c:953 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102 get_signal+0x2673/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efeb537d15c RSP: 002b:00007ffc68e83570 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: fffffffffffffe00 RBX: 0000000000000003 RCX: 00007efeb537d15c RDX: 0000000000000028 RSI: 00007ffc68e83620 RDI: 00000000000000f9 RBP: 00007ffc68e835cc R08: 0000000000000000 R09: 0079746972756365 R10: 00007ffc68e82f30 R11: 0000000000000246 R12: 0000000000000032 R13: 000000000001e57d R14: 000000000001e57d R15: 00007ffc68e83620 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 5 locks held by kworker/u8:6/1152: #0: ffff8880b8539dd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:605 #1: ffffc90003e9fd18 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #2: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #2: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1155 [inline] #2: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x20a0 arch/x86/kernel/unwind_orc.c:479 #3: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #3: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #3: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: batadv_iv_ogm_schedule_buff+0xb6c/0x14e0 net/batman-adv/bat_iv_ogm.c:849 #4: ffff888074b0ce18 (&bat_priv->forw_bat_list_lock){+...}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #4: ffff888074b0ce18 (&bat_priv->forw_bat_list_lock){+...}-{3:3}, at: batadv_forw_packet_queue+0x27/0x320 net/batman-adv/send.c:673 3 locks held by kworker/u9:1/5125: #0: ffff8880755e2148 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000fe77d18 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff8880755ccd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x175/0x430 net/bluetooth/hci_sync.c:331 1 lock held by klogd/5173: #0: ffff8880b8539dd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:605 2 locks held by getty/5570: #0: ffff888035e820a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00300-g3ce9925823c7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 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: 21176 Comm: syz.0.6949 Not tainted 6.15.0-rc5-syzkaller-00300-g3ce9925823c7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline] RIP: 0010:check_preemption_disabled+0x2c/0xe0 lib/smp_processor_id.c:19 Code: 55 53 48 83 ec 08 65 8b 1d 85 14 37 08 65 8b 05 7a 14 37 08 a9 ff ff ff 7f 74 0f 48 83 c4 08 89 d8 5b 5d 41 5c c3 cc cc cc cc <9c> 58 f6 c4 02 74 ea 48 89 fd 65 48 8b 05 3a 14 37 08 f6 40 2f 04 RSP: 0018:ffffc90003317d80 EFLAGS: 00000046 RAX: 0000000080000000 RBX: 0000000000000001 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8dcd2449 RDI: ffffffff8bf483a0 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fad53ffe6c0(0000) GS:ffff888124ae1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fad54f37a8c CR3: 00000000292a4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:467 [inline] lock_acquire kernel/locking/lockdep.c:5865 [inline] lock_acquire+0x140/0x350 kernel/locking/lockdep.c:5823 __might_fault mm/memory.c:7151 [inline] __might_fault+0x113/0x190 mm/memory.c:7145 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x29/0xd0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] __do_sys_rt_sigprocmask kernel/signal.c:3331 [inline] __se_sys_rt_sigprocmask kernel/signal.c:3318 [inline] __x64_sys_rt_sigprocmask+0x174/0x290 kernel/signal.c:3318 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fad54d351b6 Code: 10 64 48 89 04 25 00 03 00 00 48 8b 5c 24 08 41 ba 08 00 00 00 31 d2 bf 02 00 00 00 b8 0e 00 00 00 48 8d b3 f0 08 00 00 0f 05 <80> bb f8 08 00 00 00 0f 84 99 01 00 00 48 8b bb 40 06 00 00 ff 93 RSP: 002b:00007fad53ffe120 EFLAGS: 00000246 ORIG_RAX: 000000000000000e RAX: ffffffffffffffda RBX: 00007fad53ffe6c0 RCX: 00007fad54d351b6 RDX: 0000000000000000 RSI: 00007fad53ffefb0 RDI: 0000000000000002 RBP: 0000000000000000 R08: 0000000000000000 R09: 00007fff45094fd7 R10: 0000000000000008 R11: 0000000000000246 R12: ffffffffffffffa8 R13: 000000000000000b R14: 00007fff45094ef0 R15: 00007fff45094fd8