INFO: task kworker/u8:8:1148 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:8 state:D stack:21504 pid:1148 tgid:1148 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:6)
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
__schedule_loop kernel/sched/core.c:6948 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6963
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7020
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776
hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
hfsplus_cat_write_inode+0x1e6/0x7a0 fs/hfsplus/inode.c:625
write_inode fs/fs-writeback.c:1582 [inline]
__writeback_single_inode+0x7e1/0x1240 fs/fs-writeback.c:1802
writeback_sb_inodes+0x93a/0x1870 fs/fs-writeback.c:2030
__writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2107
wb_writeback+0x43f/0xaa0 fs/fs-writeback.c:2218
wb_check_old_data_flush fs/fs-writeback.c:2322 [inline]
wb_do_writeback fs/fs-writeback.c:2375 [inline]
wb_workfn+0xad2/0xed0 fs/fs-writeback.c:2403
process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Showing all locks held in the system:
3 locks held by kworker/u8:0/12:
#0:
ffff88813fe29948
(
(wq_completion)events_unbound
#2){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
#1: ffffc90000117b80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255
#2: ffffffff8f512448 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
1 lock held by khungtaskd/31:
#0: ffffffff8e13f2e0 (rcu_read_lock
){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
5 locks held by kworker/u8:7/1138:
#0: ffff88801baa7148
(
(wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
#1: ffffc900040bfb80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255
#2: ffffffff8f504e10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7a0 net/core/net_namespace.c:670
#3: ffffffff8f512448
(
rtnl_mutex
){+.+.}-{4:4}
, at: default_device_exit_batch+0xdc/0x9e0 net/core/dev.c:13041
#4: ffffffff8e144e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#4: ffffffff8e144e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:956
4 locks held by kworker/u8:8/1148:
#0: ffff888140e93948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
#1: ffffc9000414fb80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255
#2: ffff88806aaca0e0 (&type->s_umount_key#61
){++++}-{4:4}
, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3:
ffff8880223840b0
(
&tree->tree_lock
){+.+.}-{4:4}
, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
2 locks held by kworker/u8:11/3662:
#0:
ffff88801cb56948
((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
#1:
ffffc9000beefb80 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255
2 locks held by getty/5582:
#0: ffff888034afd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211
3 locks held by kworker/u8:26/8807:
#0: ffff88814d98e148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
#1: ffffc9000edefb80 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255
#2: ffffffff8f512448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f512448 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4194
8 locks held by syz.6.644/9167:
1 lock held by syz-executor/10118:
#0: ffffffff8f512448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f512448 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6964
1 lock held by syz-executor/10401:
#0:
ffffffff8f512448
(
rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
4 locks held by syz.9.817/10465:
#0: ffff8880792410a0
(
&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1:
ffff888079241130
(&tty->atomic_write_lock){+.+.}-{4:4}
, at: tty_write_lock drivers/tty/tty_io.c:939 [inline]
, at: iterate_tty_write drivers/tty/tty_io.c:958 [inline]
, at: file_tty_write+0x211/0xa20 drivers/tty/tty_io.c:1081
#2:
ffff8880792412e8
(&tty->termios_rwsem){++++}-{4:4}, at: class_rwsem_read_constructor include/linux/rwsem.h:253 [inline]
(&tty->termios_rwsem){++++}-{4:4}, at: n_tty_write+0x1e0/0x12a0 drivers/tty/n_tty.c:2349
#3: ffffc900045a9380 (&ldata->output_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#3: ffffc900045a9380 (&ldata->output_lock){+.+.}-{4:4}, at: process_output_block drivers/tty/n_tty.c:513 [inline]
#3: ffffc900045a9380 (&ldata->output_lock){+.+.}-{4:4}, at: n_tty_write+0x6a2/0x12a0 drivers/tty/n_tty.c:2366
1 lock held by syz.3.819/10473:
#0: ffffffff8e144d00 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3816
1 lock held by syz.7.822/10480:
#0:
ffffffff8e144d00
(
rcu_state.barrier_mutex
){+.+.}-{4:4}
, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3816
1 lock held by syz-executor/10482:
#0:
ffffffff8f512448
(
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978
1 lock held by syz-executor/10487:
#0:
ffffffff8f512448
(
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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:160 [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:363 [inline]
watchdog+0xe40/0xe90 kernel/hung_task.c:557
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9167 Comm: syz.6.644 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:serial_in drivers/tty/serial/8250/8250.h:-1 [inline]
RIP: 0010:serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
RIP: 0010:wait_for_lsr+0x1a1/0x2f0 drivers/tty/serial/8250/8250_port.c:1961
Code: 00 48 8b 44 24 28 80 3c 18 00 74 0a 48 8b 7c 24 18 e8 f3 78 0b fd 48 8b 7c 24 10 4c 8b 5f 50 be 05 00 00 00 2e 2e 2e 41 ff d3 <48> 8b 4c 24 20 0f b6 0c 19 84 c9 49 89 de 75 4a 0f b7 c0 41 09 c5
RSP: 0018:ffffc9000bbeea38 EFLAGS: 00000002
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffffff99e05610 R08: ffff888024998237 R09: 1ffff11004933046
R10: dffffc0000000000 R11: ffffffff851c5760 R12: 1ffffffff33c0ac2
R13: 0000000000000000 R14: dffffc0000000000 R15: 00000000000007ef
FS: 00007f6e608c56c0(0000) GS:ffff888125c25000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000fe8000 CR3: 0000000031876000 CR4: 00000000003526f0
Call Trace:
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline]
serial8250_console_write+0x134c/0x1ba0 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3129 [inline]
console_flush_one_record kernel/printk/printk.c:3215 [inline]
console_flush_all+0x745/0xb60 kernel/printk/printk.c:3289
__console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
console_unlock+0xbb/0x190 kernel/printk/printk.c:3359
vprintk_emit+0x4f8/0x5f0 kernel/printk/printk.c:2426
_printk+0xcf/0x120 kernel/printk/printk.c:2451
hfsplus_bnode_read_u16 fs/hfsplus/bnode.c:60 [inline]
hfsplus_bnode_dump+0x16b/0xa00 fs/hfsplus/bnode.c:362
hfsplus_brec_remove+0x61c/0x700 fs/hfsplus/brec.c:229
__hfsplus_delete_attr+0x1d4/0x360 fs/hfsplus/attributes.c:299
hfsplus_delete_attr+0x239/0x3b0 fs/hfsplus/attributes.c:345
__hfsplus_setxattr+0x396/0x2170 fs/hfsplus/xattr.c:344
hfsplus_setxattr+0x11e/0x180 fs/hfsplus/xattr.c:434
hfsplus_trusted_setxattr+0x40/0x60 fs/hfsplus/xattr_trusted.c:30
__vfs_setxattr+0x43c/0x480 fs/xattr.c:200
__vfs_setxattr_noperm+0x12d/0x660 fs/xattr.c:234
vfs_setxattr+0x162/0x360 fs/xattr.c:321
do_setxattr fs/xattr.c:636 [inline]
filename_setxattr+0x274/0x600 fs/xattr.c:665
path_setxattrat+0x364/0x3a0 fs/xattr.c:713
__do_sys_lsetxattr fs/xattr.c:754 [inline]
__se_sys_lsetxattr fs/xattr.c:750 [inline]
__x64_sys_lsetxattr+0xbf/0xe0 fs/xattr.c:750
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6e5f98f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6e608c5038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007f6e5fbe6090 RCX: 00007f6e5f98f749
RDX: 00002000000001c0 RSI: 0000200000000180 RDI: 00002000000001c0
RBP: 00007f6e5fa13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000361 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6e5fbe6128 R14: 00007f6e5fbe6090 R15: 00007ffc7f347488