INFO: task syz-executor:8393 blocked for more than 143 seconds.
Not tainted 6.14.0-rc7-syzkaller-00205-g586de92313fc #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:20448 pid:8393 tgid:8393 ppid:1 task_flags:0x40014c flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0x190e/0x4c90 kernel/sched/core.c:6765
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6857
wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:216
sync_inodes_sb+0x28d/0xb50 fs/fs-writeback.c:2821
sync_filesystem+0x176/0x230 fs/sync.c:64
generic_shutdown_super+0x72/0x2d0 fs/super.c:621
kill_block_super+0x44/0x90 fs/super.c:1710
ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7368
deactivate_locked_super+0xc6/0x130 fs/super.c:473
cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1413
task_work_run+0x251/0x310 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0xa2a/0x2940 kernel/exit.c:938
do_group_exit+0x207/0x2c0 kernel/exit.c:1087
__do_sys_exit_group kernel/exit.c:1098 [inline]
__se_sys_exit_group kernel/exit.c:1096 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096
x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbd6cd8d169
RSP: 002b:00007ffdf0552798 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fbd6ce0e0fe RCX: 00007fbd6cd8d169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000010 R08: 00007ffdf0550536 R09: 00007ffdf0553a50
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdf0553a50
R13: 00007fbd6ce0e08c R14: 000055557210d4a8 R15: 00007ffdf0554b20
INFO: task syz.0.1129:10511 blocked for more than 144 seconds.
Not tainted 6.14.0-rc7-syzkaller-00205-g586de92313fc #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1129 state:D stack:24928 pid:10511 tgid:10510 ppid:9585 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0x190e/0x4c90 kernel/sched/core.c:6765
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6857
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914
rwsem_down_read_slowpath kernel/locking/rwsem.c:1084 [inline]
__down_read_common kernel/locking/rwsem.c:1248 [inline]
__down_read kernel/locking/rwsem.c:1261 [inline]
down_read+0x705/0xa40 kernel/locking/rwsem.c:1526
__super_lock fs/super.c:58 [inline]
super_lock+0x27c/0x400 fs/super.c:120
super_lock_shared fs/super.c:139 [inline]
iterate_supers+0x8c/0x190 fs/super.c:931
ksys_sync+0xbd/0x1c0 fs/sync.c:102
__do_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff99f78d169
RSP: 002b:00007ff9a0637038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007ff99f9a5fa0 RCX: 00007ff99f78d169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ff99f9a5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff99f9a5fa0 R15: 00007fffdd499108
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
2 locks held by getty/5593:
#0: ffff88814d5620a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211
3 locks held by kworker/0:3/5902:
#0: ffff88801b078d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b078d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
#1: ffffc9000417fc60 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000417fc60 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
#2: ffffffff8eb3e8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline]
#2: ffffffff8eb3e8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996
3 locks held by kworker/u8:10/6175:
3 locks held by kworker/u8:11/6318:
#0: ffff88801b081148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b081148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
#1: ffffc9000508fc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000508fc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
#2: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:285
3 locks held by kworker/u8:13/6878:
2 locks held by syz-executor/8393:
#0: ffff88803bdc40e0 (&type->s_umount_key#31){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline]
#0: ffff88803bdc40e0 (&type->s_umount_key#31){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff88803bdc40e0 (&type->s_umount_key#31){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505
#1: ffff8881437907d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff8881437907d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2819
4 locks held by kworker/u8:17/9126:
#0: ffff8880206c5948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff8880206c5948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
#1: ffffc90003517c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003517c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
#2: ffff8880348420e0 (&type->s_umount_key#31){++++}-{4:4}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562
#3: ffff888034844b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1773 [inline]
#3: ffff888034844b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1bf/0x3c0 fs/ext4/inode.c:2823
2 locks held by syz-executor/9196:
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517
#1: ffffffff8eb3e8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline]
#1: ffffffff8eb3e8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996
1 lock held by syz.4.910/9646:
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517
1 lock held by syz.0.1129/10511:
#0: ffff88803bdc40e0 (&type->s_umount_key#31){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88803bdc40e0 (&type->s_umount_key#31){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
1 lock held by syz.8.1225/10964:
#0: ffff88803bdc40e0 (&type->s_umount_key#31){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88803bdc40e0 (&type->s_umount_key#31){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
1 lock held by syz.8.1225/10965:
#0: ffff88803bdc40e0 (&type->s_umount_key#31){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88803bdc40e0 (&type->s_umount_key#31){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
1 lock held by syz.3.1236/11016:
#0: ffff88803bdc40e0 (&type->s_umount_key#31){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88803bdc40e0 (&type->s_umount_key#31){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
3 locks held by syz-executor/11152:
#0: ffff888011ce8d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline]
#0: ffff888011ce8d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2678
#1: ffff888011ce8078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x60d/0x1260 net/bluetooth/hci_sync.c:5185
#2: ffffffff9003b928 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2041 [inline]
#2: ffffffff9003b928 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2698
1 lock held by syz.1.1445/11889:
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517
4 locks held by syz-executor/11912:
#0: ffff88805bab8d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline]
#0: ffff88805bab8d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2678
#1: ffff88805bab8078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x60d/0x1260 net/bluetooth/hci_sync.c:5185
#2: ffffffff9003b928 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2041 [inline]
#2: ffffffff9003b928 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2698
#3: ffff888065eac338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x71/0x690 net/bluetooth/l2cap_core.c:1761
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00205-g586de92313fc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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:236 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:399
kthread+0x7ab/0x920 kernel/kthread.c:464
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
IPVS: fo: UDP 224.0.0.2:0 - no destination available
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111