INFO: task syz.1.256:7932 blocked in I/O wait for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.256 state:D stack:25088 pid:7932 tgid:7931 ppid:5606 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x16ec/0x5620 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
io_schedule+0x7f/0xd0 kernel/sched/core.c:8110
folio_wait_bit_common+0x6dd/0xbc0 mm/filemap.c:1324
folio_lock include/linux/pagemap.h:1159 [inline]
release_metapage+0x103/0xa90 fs/jfs/jfs_metapage.c:871
discard_metapage fs/jfs/jfs_metapage.h:88 [inline]
__get_metapage+0x9dc/0xe20 fs/jfs/jfs_metapage.c:754
dtSearch+0x5e1/0x2280 fs/jfs/jfs_dtree.c:621
jfs_lookup+0x1b0/0x420 fs/jfs/namei.c:1464
lookup_open fs/namei.c:4484 [inline]
open_last_lookups fs/namei.c:4611 [inline]
path_openat+0x11cb/0x38a0 fs/namei.c:4855
do_file_open+0x23e/0x4a0 fs/namei.c:4887
do_sys_openat2+0x113/0x200 fs/open.c:1364
do_sys_open fs/open.c:1370 [inline]
__do_sys_creat fs/open.c:1448 [inline]
__se_sys_creat fs/open.c:1442 [inline]
__x64_sys_creat+0x8f/0xc0 fs/open.c:1442
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe12e73ce59
RSP: 002b:00007fe12c98e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007fe12e9b5fa0 RCX: 00007fe12e73ce59
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000200000000380
RBP: 00007fe12e7d2d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe12e9b6038 R14: 00007fe12e9b5fa0 R15: 00007ffc89405fc8
INFO: task syz.1.256:7940 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.256 state:D stack:25592 pid:7940 tgid:7931 ppid:5606 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x16ec/0x5620 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7564
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1662 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1739 [inline]
__rt_mutex_slowlock_locked+0x1f28/0x2550 kernel/locking/rtmutex.c:1779
rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1819
__rt_mutex_lock kernel/locking/rtmutex.c:1834 [inline]
rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:245
inode_lock_nested include/linux/fs.h:1074 [inline]
__start_dirop fs/namei.c:2914 [inline]
start_dirop fs/namei.c:2938 [inline]
filename_create+0x200/0x370 fs/namei.c:4950
filename_mknodat+0x18c/0x670 fs/namei.c:5158
__do_sys_mknod fs/namei.c:5207 [inline]
__se_sys_mknod+0x3a/0x150 fs/namei.c:5204
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe12e73ce59
RSP: 002b:00007fe12c96d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000085
RAX: ffffffffffffffda RBX: 00007fe12e9b6090 RCX: 00007fe12e73ce59
RDX: 0000000000000703 RSI: 0000000000002000 RDI: 00002000000009c0
RBP: 00007fe12e7d2d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe12e9b6128 R14: 00007fe12e9b6090 R15: 00007ffc89405fc8
Showing all locks held in the system:
4 locks held by pr/legacy/17:
1 lock held by khungtaskd/38:
#0: ffffffff8dfc8000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8dfc8000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8dfc8000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
8 locks held by kworker/u8:4/66:
3 locks held by kworker/u8:5/68:
#0: ffff88803272f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
#0: ffff88803272f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
#1: ffffc9000153fc40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
#1: ffffc9000153fc40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
#2: ffffffff8f34fcf8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f34fcf8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4746
3 locks held by kworker/u8:6/151:
#0: ffff88801f2af138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
#0: ffff88801f2af138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
#1: ffffc900038cfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
#1: ffffc900038cfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
#2: ffff88802c1860d0 (&type->s_umount_key#66){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
3 locks held by kworker/u8:14/3687:
#0: ffff88801a074138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
#0: ffff88801a074138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
#1: ffffc9000ee07c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
#1: ffffc9000ee07c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
#2: ffffffff8f34fcf8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
1 lock held by udevd/4970:
#0: ffff88801a07f2c0 (&root->kernfs_iattr_rwsem){++++}-{4:4}, at: kernfs_iop_permission+0x7f/0x430 fs/kernfs/inode.c:288
2 locks held by dhcpcd/5265:
#0: ffff8880425c2928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2409
#1: ffffffff8f34fcf8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f34fcf8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6865
2 locks held by getty/5360:
#0: ffff8880289820a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/7276:
1 lock held by syz-executor/7822:
#0: ffff8880643260d0 (&type->s_umount_key#33){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880643260d0 (&type->s_umount_key#33){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff8880643260d0 (&type->s_umount_key#33){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
1 lock held by syz.1.256/7932:
#0: ffff88806081ac58 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
#0: ffff88806081ac58 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: open_last_lookups fs/namei.c:4608 [inline]
#0: ffff88806081ac58 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: path_openat+0xb5e/0x38a0 fs/namei.c:4855
1 lock held by syz.1.256/7940:
#0: ffff88806081ac58 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1074 [inline]
#0: ffff88806081ac58 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2914 [inline]
#0: ffff88806081ac58 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2938 [inline]
#0: ffff88806081ac58 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4950
4 locks held by kworker/u8:15/8558:
#0: ffff88801b290938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
#0: ffff88801b290938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
#1: ffffc90004eafc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
#1: ffffc90004eafc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
#2: ffffffff8f340fa0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:673
#3: ffffffff8f34fcf8 (rtnl_mutex){+.+.}-{4:4}, at: wg_destruct+0x25/0x310 drivers/net/wireguard/device.c:246
10 locks held by syz-executor/9452:
9 locks held by syz.4.404/9649:
3 locks held by syz.3.406/9653:
1 lock held by udevadm/9692:
#0: ffff88801a07f2c0 (&root->kernfs_iattr_rwsem){++++}-{4:4}, at: kernfs_iop_permission+0x7f/0x430 fs/kernfs/inode.c:288
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:401
Code: e8 6e 1e 90 fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 df 4b f7 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 8a fe ea 05 cc 44 89 f9 80 e1 07
RSP: 0018:ffffc900001679d0 EFLAGS: 00000202
RAX: 1ffffffff3361500 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff99b0abb0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff85344d50 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff99b0a920 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888126183000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffdf6fa186c CR3: 00000000370da000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x1aa/0x2f0 drivers/tty/serial/8250/8250_port.c:1973
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3210 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3275 [inline]
serial8250_console_write+0x120d/0x1b90 drivers/tty/serial/8250/8250_port.c:3360
console_emit_next_record kernel/printk/printk.c:3163 [inline]
console_flush_one_record+0x68b/0xb90 kernel/printk/printk.c:3269
legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3712
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245