INFO: task syz-executor:5609 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21152 pid:5609 tgid:5609 ppid:1 task_flags:0x40014c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1709/0x5530 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
wb_wait_for_completion+0x3b2/0x700 fs/fs-writeback.c:227
sync_inodes_sb+0x226/0xc30 fs/fs-writeback.c:3030
sync_filesystem+0x179/0x250 fs/sync.c:64
generic_shutdown_super+0x77/0x2d0 fs/super.c:626
kill_block_super+0x44/0x90 fs/super.c:1665
ext4_kill_sb+0x68/0xb0 fs/ext4/super.c:7499
deactivate_locked_super+0xbc/0x130 fs/super.c:477
cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317
task_work_run+0x1d9/0x270 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x73a/0x2360 kernel/exit.c:1004
do_group_exit+0x22d/0x2f0 kernel/exit.c:1147
__do_sys_exit_group kernel/exit.c:1158 [inline]
__se_sys_exit_group kernel/exit.c:1156 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1156
x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232
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: 0033:0x7f36ac22ce59
RSP: 002b:00007ffd54434ba8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f36ac2c22ef RCX: 00007f36ac22ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 000000000000000c R08: 0000000000000000 R09: 00007f36ac2c22ca
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd54435e60
R13: 00007f36ac2c22ca R14: 00000000000624a3 R15: 00007ffd54436f30
Showing all locks held in the system:
6 locks held by kworker/u8:1/14:
#0: ffff88813fe8c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#1: ffffc90000137c60 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#2: ffff88801e2ba310 (&devlink->lock_key#3){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xcb0 drivers/net/netdevsim/dev.c:909
#3: ffff88804003fd20 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#3: ffff88804003fd20 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: nsim_dev_trap_report drivers/net/netdevsim/dev.c:862 [inline]
#3: ffff88804003fd20 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x1e0/0xcb0 drivers/net/netdevsim/dev.c:922
#4: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#4: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#4: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#4: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
#5: ffffffff99ac10e0 (&obj_hash[i].lock){-...}-{2:2}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#5: ffffffff99ac10e0 (&obj_hash[i].lock){-...}-{2:2}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#5: ffffffff99ac10e0 (&obj_hash[i].lock){-...}-{2:2}, at: class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
#5: ffffffff99ac10e0 (&obj_hash[i].lock){-...}-{2:2}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495
1 lock held by khungtaskd/38:
#0: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777
4 locks held by kworker/u8:6/163:
#0: ffff88801b696138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#1: ffffc90003a17c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#2: ffffffff8f37a900 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:673
#3: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
#3: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x28e/0x8d0 net/core/net_namespace.c:248
7 locks held by kworker/0:2/202:
#0: ffff88813fe4a538 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#1: ffffc90003b37c60 ((work_completion)(&(&tbl->gc_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#2: ffffffff8de591e0 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163
#3: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163
#4: ffffffff8f4b89b8 (&tbl->lock){+...}-{3:3}, at: spin_lock_bh include/linux/spinlock_rt.h:90 [inline]
#4: ffffffff8f4b89b8 (&tbl->lock){+...}-{3:3}, at: neigh_periodic_work+0xc6b/0xe90 net/core/neighbour.c:1037
#5: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#5: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#5: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#5: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
#6: ffff88803549d0a8 (&n->lock){++..}-{3:3}, at: write_lock include/linux/rwlock_rt.h:92 [inline]
#6: ffff88803549d0a8 (&n->lock){++..}-{3:3}, at: neigh_periodic_work+0x466/0xe90 net/core/neighbour.c:1004
3 locks held by kworker/u8:11/3301:
#0: ffff88813fe8c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#1: ffffc9000dd1fc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#2: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
3 locks held by kworker/u8:13/4293:
#0: ffff888031eb8138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#1: ffffc9000eb1fc60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#2: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x123/0x16e0 net/ipv6/addrconf.c:4223
4 locks held by kworker/u8:14/4294:
#0: ffff88801f2bf138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#1: ffffc9000eb9fc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#2: ffff88806d114cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
#2: ffff88806d114cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1876 [inline]
#2: ffff88806d114cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x205/0x3b0 fs/ext4/inode.c:3042
#3: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#3: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#3: ffffffff8dfc3080 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
2 locks held by dhcpcd/5271:
#0: ffffffff8f36a338 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5ee/0x7f0 net/socket.c:1398
#1: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xf0/0x630 net/8021q/vlan.c:579
2 locks held by getty/5361:
#0: ffff88803511c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/5609:
#0: ffff8880349620d0 (&type->s_umount_key#34){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880349620d0 (&type->s_umount_key#34){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff8880349620d0 (&type->s_umount_key#34){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:509
#1: ffff8880263f0920 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:396 [inline]
#1: ffff8880263f0920 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x20f/0xc30 fs/fs-writeback.c:3028
1 lock held by syz-executor/9834:
#0: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x464/0x19e0 net/ipv4/devinet.c:978
7 locks held by syz-executor/9971:
#0: ffff888036334500 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2728 [inline]
#0: ffff888036334500 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff88805e1bf878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029a77d28 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029a77d28 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffffffff8ebfeeb8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234
#4: ffff88802bf7a160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#4: ffff88802bf7a160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline]
#4: ffff88802bf7a160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb9/0x880 drivers/base/dd.c:1369
#5: ffff8880330e6310 (&devlink->lock_key#19){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1799
#6: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#6: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2164
4 locks held by syz-executor/9980:
#0: ffff888036334500 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2728 [inline]
#0: ffff888036334500 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff88802bbf6878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029a77e18 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029a77e18 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffffffff8ebfeeb8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x13c/0x710 drivers/net/netdevsim/bus.c:184
3 locks held by kworker/0:1/10117:
#0: ffff88813fe4b938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#1: ffffc90003dd7c60 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x8cd/0x12b0 kernel/workqueue.c:3301
#2: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
1 lock held by syz-executor/10196:
#0: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f389ef8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x464/0x19e0 net/ipv4/devinet.c:978
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
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+0xfd7/0x1030 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 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:preempt_count_add+0x6/0x190 kernel/sched/core.c:5972
Code: 50 6e 9d 00 e9 70 ff ff ff e9 d3 fe ff ff 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 <41> 56 53 49 bf 00 00 00 00 00 fc ff df 48 c7 c0 80 75 80 99 48 c1
RSP: 0018:ffffc90000167a18 EFLAGS: 00000286
RAX: 0000000080000000 RBX: 0000000000000899 RCX: 0000000000000000
RDX: 0000000000000128 RSI: ffffffff8baa6360 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff8b2f98d0 R12: 1ffffffff3377dfa
R13: 00000000ffffffff R14: 0000012808070088 R15: 0000000000000122
FS: 0000000000000000(0000) GS:ffff888125ecd000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f94309ecff8 CR3: 000000003e610000 CR4: 00000000003526f0
Call Trace:
delay_tsc+0x65/0xc0 arch/x86/lib/delay.c:79
udelay include/asm-generic/delay.h:62 [inline]
wait_for_lsr+0x14d/0x300 drivers/tty/serial/8250/8250_port.c:1988
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3229 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3294 [inline]
serial8250_console_write+0x113a/0x1b40 drivers/tty/serial/8250/8250_port.c:3379
console_emit_next_record kernel/printk/printk.c:3163 [inline]
console_flush_one_record+0x642/0xb50 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