INFO: task syz.2.267:8421 blocked for more than 143 seconds.
Tainted: G W 6.16.0-syzkaller-06699-ge8d780dcd957 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.267 state:D stack:25432 pid:8421 tgid:8420 ppid:5819 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5351 [inline]
__schedule+0x16b2/0x4ca0 kernel/sched/core.c:6954
__schedule_loop kernel/sched/core.c:7036 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7051
io_schedule+0x81/0xe0 kernel/sched/core.c:7896
folio_wait_bit_common+0x6b5/0xb90 mm/filemap.c:1317
folio_lock include/linux/pagemap.h:1141 [inline]
release_metapage+0x103/0xab0 fs/jfs/jfs_metapage.c:868
discard_metapage fs/jfs/jfs_metapage.h:88 [inline]
__get_metapage+0x9a0/0xde0 fs/jfs/jfs_metapage.c:751
dtSplitPage+0x7f8/0x3b20 fs/jfs/jfs_dtree.c:1471
dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline]
dtInsert+0x109b/0x5f40 fs/jfs/jfs_dtree.c:871
jfs_mkdir+0x6ec/0xa70 fs/jfs/namei.c:270
vfs_mkdir+0x303/0x510 fs/namei.c:4366
do_mkdirat+0x247/0x590 fs/namei.c:4399
__do_sys_mkdir fs/namei.c:4421 [inline]
__se_sys_mkdir fs/namei.c:4419 [inline]
__x64_sys_mkdir+0x6c/0x80 fs/namei.c:4419
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fac9d5de9a9
RSP: 002b:00007fac9b43e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007fac9d805fa0 RCX: 00007fac9d5de9a9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000300
RBP: 00007fac9d660d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fac9d805fa0 R15: 00007fffb01431b8
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d7aa0c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d7aa0c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8d7aa0c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:3/57:
4 locks held by kworker/u8:8/2149:
#0: ffff88801e2e1138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801e2e1138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90005b2fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90005b2fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff88803805e0d0 (&type->s_umount_key#74){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff88803dcc1588 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
3 locks held by kworker/u8:13/4164:
1 lock held by dhcpcd/5476:
#0: ffffffff8eaa4438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8eaa4438 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979
2 locks held by getty/5572:
#0: ffff88823bf380a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900042062e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222
4 locks held by syz.2.267/8421:
#0: ffff88803805e488 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88803dcc1958 (&type->i_mutex_dir_key#17/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#1: ffff88803dcc1958 (&type->i_mutex_dir_key#17/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0 fs/namei.c:4139
#2: ffff88803dcc1588 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_mkdir+0x1fb/0xa70 fs/jfs/namei.c:233
#3: ffff88803dcc5068 (&jfs_ip->commit_mutex/1){+.+.}-{4:4}, at: jfs_mkdir+0x216/0xa70 fs/jfs/namei.c:234
1 lock held by syz-executor/8471:
1 lock held by syz-executor/8621:
#0: ffffffff8d40c0a8 (tasklist_lock){++++}-{3:3}, at: read_lock include/linux/rwlock_rt.h:37 [inline]
#0: ffffffff8d40c0a8 (tasklist_lock){++++}-{3:3}, at: __do_wait+0xe1/0x740 kernel/exit.c:1665
3 locks held by kworker/u8:14/9147:
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc900042cfbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900042cfbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8eaa4438 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
2 locks held by syz.5.425/9831:
#0: ffff88803805e0d0 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88803805e0d0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
#1: ffff88802467a870 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff88802467a870 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19b/0xa50 fs/fs-writeback.c:2831
2 locks held by syz-executor/9904:
#0: ffffffff8e237780 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e237780 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e237780 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8eaa4438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8eaa4438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8eaa4438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056
2 locks held by syz-executor/10044:
#0: ffffffff8ea97560 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566
#1: ffffffff8eaa4438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#1: ffffffff8eaa4438 (rtnl_mutex){+.+.}-{4:4}, at: register_netdevice_notifier_net+0x1a/0xa0 net/core/dev.c:2082
2 locks held by syz.6.460/10049:
2 locks held by syz.9.462/10089:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Tainted: G W 6.16.0-syzkaller-06699-ge8d780dcd957 #0 PREEMPT_{RT,(full)}
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:470
kthread+0x70e/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: 57 Comm: kworker/u8:3 Tainted: G W 6.16.0-syzkaller-06699-ge8d780dcd957 #0 PREEMPT_{RT,(full)}
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: netns cleanup_net
RIP: 0010:chain_hlock_class_idx kernel/locking/lockdep.c:438 [inline]
RIP: 0010:remove_class_from_lock_chain kernel/locking/lockdep.c:6198 [inline]
RIP: 0010:remove_class_from_lock_chains kernel/locking/lockdep.c:6236 [inline]
RIP: 0010:zap_class+0xe5/0x360 kernel/locking/lockdep.c:6281
Code: c1 75 d7 45 8b 7d 00 41 f6 c7 fc 0f 84 e2 00 00 00 41 c1 ef 08 4e 8d 34 7d d0 f2 d8 91 49 81 ff 00 00 50 00 73 30 41 0f b7 06 <25> ff 1f 00 00 48 39 c3 74 33 49 ff c7 41 8b 45 00 89 c1 c1 e9 08
RSP: 0018:ffffc9000123f538 EFLAGS: 00000087
RAX: 000000000000098e RBX: 0000000000000f70 RCX: 0000000000076600
RDX: ffffffff92d5f328 RSI: ffffffff92d5f328 RDI: ffffffff92850260
RBP: ffffffff92d7f770 R08: 0000000000000000 R09: ffffffff81a94de8
R10: dffffc0000000000 R11: fffffbfff1df4a1f R12: 0000000000005256
R13: ffffffff931580b0 R14: ffffffff91efc384 R15: 00000000000b685a
FS: 0000000000000000(0000) GS:ffff888126c1c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb6d121c000 CR3: 0000000035764000 CR4: 00000000003526f0
Call Trace:
__lockdep_free_key_range kernel/locking/lockdep.c:6407 [inline]
lockdep_unregister_key+0x1a6/0x310 kernel/locking/lockdep.c:6609
__qdisc_destroy+0x166/0x420 net/sched/sch_generic.c:1083
qdisc_put net/sched/sch_generic.c:1109 [inline]
dev_shutdown+0x34c/0x440 net/sched/sch_generic.c:1497
unregister_netdevice_many_notify+0xe0f/0x1fe0 net/core/dev.c:12144
unregister_netdevice_many net/core/dev.c:12219 [inline]
default_device_exit_batch+0x819/0x890 net/core/dev.c:12723
ops_exit_list net/core/net_namespace.c:204 [inline]
ops_undo_list+0x522/0x990 net/core/net_namespace.c:251
cleanup_net+0x4cb/0x800 net/core/net_namespace.c:682
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/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