INFO: task kworker/u8:0:12 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:0 state:D stack:20232 pid:12 tgid:12 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
jfs_write_inode+0x145/0x220 fs/jfs/inode.c:138
write_inode fs/fs-writeback.c:1582 [inline]
__writeback_single_inode+0x75a/0x11a0 fs/fs-writeback.c:1825
writeback_sb_inodes+0x992/0x1a20 fs/fs-writeback.c:2054
__writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2130
wb_writeback+0x46a/0xb70 fs/fs-writeback.c:2241
wb_check_start_all fs/fs-writeback.c:2367 [inline]
wb_do_writeback fs/fs-writeback.c:2393 [inline]
wb_workfn+0x95b/0xf50 fs/fs-writeback.c:2426
process_one_work kernel/workqueue.c:3276 [inline]
process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task syz.0.2394:15940 blocked for more than 145 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2394 state:D stack:28832 pid:15940 tgid:15906 ppid:14711 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
rwsem_down_write_slowpath+0x899/0x1040 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write_nested+0x1c6/0x210 kernel/locking/rwsem.c:1707
inode_lock_nested include/linux/fs.h:1073 [inline]
__start_dirop fs/namei.c:2929 [inline]
start_dirop fs/namei.c:2940 [inline]
filename_create+0x200/0x370 fs/namei.c:4928
filename_mkdirat+0xd2/0x510 fs/namei.c:5265
__do_sys_mkdir fs/namei.c:5299 [inline]
__se_sys_mkdir+0x34/0x150 fs/namei.c:5296
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f55b139c819
RSP: 002b:00007f55b21e8028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f55b1616090 RCX: 00007f55b139c819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000400
RBP: 00007f55b1432c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f55b1616128 R14: 00007f55b1616090 R15: 00007fffa3a4e0c8
INFO: task syz.0.2394:15943 blocked for more than 145 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2394 state:D stack:25896 pid:15943 tgid:15906 ppid:14711 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
rwsem_down_write_slowpath+0x899/0x1040 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write_nested+0x1c6/0x210 kernel/locking/rwsem.c:1707
inode_lock_nested include/linux/fs.h:1073 [inline]
lock_rename fs/namei.c:3762 [inline]
__start_renaming+0x148/0x410 fs/namei.c:3858
filename_renameat2+0x38c/0x9c0 fs/namei.c:6125
__do_sys_rename fs/namei.c:6194 [inline]
__se_sys_rename+0x55/0x2c0 fs/namei.c:6190
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f55b139c819
RSP: 002b:00007f55b21c7028 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007f55b1616180 RCX: 00007f55b139c819
RDX: 0000000000000000 RSI: 0000200000000f40 RDI: 00002000000003c0
RBP: 00007f55b1432c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f55b1616218 R14: 00007f55b1616180 R15: 00007fffa3a4e0c8
INFO: task syz.8.2416:15993 blocked for more than 146 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.2416 state:D stack:24960 pid:15993 tgid:15992 ppid:9015 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
wb_wait_for_completion+0x3e8/0x790 fs/fs-writeback.c:227
sync_inodes_sb+0x225/0xbf0 fs/fs-writeback.c:2942
__iterate_supers+0x13d/0x290 fs/super.c:927
ksys_sync fs/sync.c:102 [inline]
__ia32_sys_sync+0xa0/0x120 fs/sync.c:111
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbfc099c819
RSP: 002b:00007fbfbebf6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fbfc0c15fa0 RCX: 00007fbfc099c819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fbfc0c15fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbfc0c16038 R14: 00007fbfc0c15fa0 R15: 00007ffddefd9678
Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
#0: ffffffff8e7648f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#0: ffffffff8e7648f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
4 locks held by kworker/u8:0/12:
#0: ffff88801fee0148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff88801fee0148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc90000117c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc90000117c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffff8880252c20e0 (&type->s_umount_key#67){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff888058f0d430 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
1 lock held by khungtaskd/32:
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by dhcpcd/5484:
2 locks held by getty/5577:
#0: ffff888036d910a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900033262f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
5 locks held by syz.0.2394/15909:
2 locks held by syz.0.2394/15940:
#0: ffff8880252c2420 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff888058f0d7e0 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff888058f0d7e0 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2929 [inline]
#1: ffff888058f0d7e0 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2940 [inline]
#1: ffff888058f0d7e0 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4928
2 locks held by syz.0.2394/15943:
#0: ffff8880252c2420 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff888058f0d7e0 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff888058f0d7e0 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3762 [inline]
#1: ffff888058f0d7e0 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: __start_renaming+0x148/0x410 fs/namei.c:3858
2 locks held by syz.8.2416/15993:
#0: ffff8880252c20e0 (&type->s_umount_key#67){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff8880252c20e0 (&type->s_umount_key#67){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
#1: ffff888025f92820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:398 [inline]
#1: ffff888025f92820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x209/0xbf0 fs/fs-writeback.c:2940
2 locks held by syz.5.2778/17722:
#0: ffffffff8fbc18d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:577
#1: ffffffff8e7647c0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
2 locks held by syz.1.2786/17756:
#0: ffffffff8fbc18d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:577
#1: ffffffff8e7647c0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
2 locks held by dhcpcd/17774:
#0: ffff88807df72260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
#0: ffff88807df72260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe10 net/packet/af_packet.c:3198
#1: ffffffff8e7648f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8e7648f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
6 locks held by sed/17780:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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:161 [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:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
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: 15909 Comm: syz.0.2394 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:dtSplitRoot+0x793/0x16c0 fs/jfs/jfs_dtree.c:1980
Code: b6 f5 bf ff 00 00 00 e8 5b ca 68 fe 40 84 ed 78 33 e8 51 c7 68 fe 48 c1 e5 05 4c 01 ed 49 89 ed 49 c1 ed 03 43 0f b6 44 25 00 <84> c0 75 2b 44 0f b6 75 00 45 84 f6 78 34 e8 2a c7 68 fe 4c 8b 6c
RSP: 0018:ffffc9000e477688 EFLAGS: 00000216
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000080000
RDX: ffffc9001fd3d000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffff888057d92000 R08: ffff888057d9211f R09: 1ffff1100afb2423
R10: dffffc0000000000 R11: ffffed100afb2424 R12: dffffc0000000000
R13: 1ffff1100afb2400 R14: 0000000000000000 R15: 1ffff1100afb2402
FS: 00007f55b22096c0(0000) GS:ffff888125557000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffdcee6b318 CR3: 0000000035ab3000 CR4: 0000000000350ef0
Call Trace:
dtSplitUp fs/jfs/jfs_dtree.c:993 [inline]
dtInsert+0xf19/0x5f10 fs/jfs/jfs_dtree.c:871
jfs_link+0x370/0x610 fs/jfs/namei.c:827
vfs_link+0x518/0x6e0 fs/namei.c:5752
filename_linkat+0x273/0x600 fs/namei.c:5820
__do_sys_link fs/namei.c:5853 [inline]
__se_sys_link+0x55/0x2c0 fs/namei.c:5849
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f55b139c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f55b2209028 EFLAGS: 00000246 ORIG_RAX: 0000000000000056
RAX: ffffffffffffffda RBX: 00007f55b1615fa0 RCX: 00007f55b139c819
RDX: 0000000000000000 RSI: 0000200000000240 RDI: 00002000000001c0
RBP: 00007f55b1432c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f55b1616038 R14: 00007f55b1615fa0 R15: 00007fffa3a4e0c8