INFO: task syz.2.260:5093 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.260 state:D stack:27056 pid:5093 ppid:4271 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6698
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x548/0xae0 kernel/locking/mutex.c:747
write_recoverydir+0xea/0x2e0 fs/nfsd/nfsctl.c:1083
nfsctl_transaction_write fs/nfsd/nfsctl.c:114 [inline]
nfsctl_transaction_read+0x165/0x1b0 fs/nfsd/nfsctl.c:129
vfs_read+0x2db/0x960 fs/read_write.c:468
ksys_read+0x14d/0x260 fs/read_write.c:613
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f49add9e559
RSP: 002b:00007f49aebf3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f49ae025fa0 RCX: 00007f49add9e559
RDX: 0000000000000064 RSI: 0000200000000200 RDI: 0000000000000003
RBP: 00007f49ade35ad8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f49ae026038 R14: 00007f49ae025fa0 R15: 00007ffe3b7a20f8
</TASK>
Showing all locks held in the system:
3 locks held by kworker/u4:1/11:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8d92e230 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8d92ea50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
3 locks held by kworker/1:1/26:
#0: ffff88814d603d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc90000a2fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#2: ffffffff8eb566e8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1500 net/ipv6/addrconf.c:4146
1 lock held by khungtaskd/28:
#0: ffffffff8d92d8a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8d92d8a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8d92d8a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6669
3 locks held by kworker/u4:4/57:
#0: ffff8880b8c3acd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x25/0x130 kernel/sched/core.c:538
#1: ffff8880b8c27888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x400/0x740 kernel/sched/psi.c:999
#2: ffff8880b8c27888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_change+0xdc/0x240 kernel/sched/psi.c:924
1 lock held by dhcpcd/3932:
#0: ffffffff8eb566e8 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x27f/0x1bf0 net/ipv4/devinet.c:1080
2 locks held by getty/4026:
#0: ffff88814d81c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
2 locks held by syz-executor/4281:
#0: ffff8880289ba0e0 (&type->s_umount_key#81){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffffffff8dbcc888 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x4f/0x1a0 fs/nfsd/nfssvc.c:633
2 locks held by kworker/0:8/4403:
#0: ffff888018472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc9000498fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
3 locks held by syz.0.171/4822:
#0: ffff88807c3b05e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038
#1: ffff888030c76460 (sb_writers#24){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580
#2: ffffffff8dbcc888 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_svc+0x61/0xab0 fs/nfsd/nfssvc.c:783
2 locks held by syz-executor/4940:
#0: ffff88807adde0e0 (&type->s_umount_key#81){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffffffff8dbcc888 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x4f/0x1a0 fs/nfsd/nfssvc.c:633
2 locks held by syz.2.260/5093:
#0: ffff88803089e368 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038
#1: ffffffff8dbcc888 (nfsd_mutex){+.+.}-{3:3}, at: write_recoverydir+0xea/0x2e0 fs/nfsd/nfsctl.c:1083
2 locks held by syz-executor/5257:
#0: ffff88805020c0e0 (&type->s_umount_key#81){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffffffff8dbcc888 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x4f/0x1a0 fs/nfsd/nfssvc.c:633
2 locks held by syz-executor/5555:
#0: ffff88804b06d1e0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
#0: ffff88804b06d1e0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x20e/0x500 net/bluetooth/hci_core.c:2718
#1: ffff88804b06c428 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x506/0x1060 net/bluetooth/hci_sync.c:5300
3 locks held by syz.1.477/5838:
#0: ffff88807a838368 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038
#1: ffff8880534ba460 (sb_writers#24){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580
#2: ffffffff8dbcc888 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb3/0xb80 fs/nfsd/nfsctl.c:846
3 locks held by kworker/0:10/5945:
#0: ffff888018470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc9000d81fd00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#2: ffffffff8d933578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#2: ffffffff8d933578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962
1 lock held by syz.9.696/6690:
#0: ffff88807adde0e0 (&type->s_umount_key#81){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:755
2 locks held by syz-executor/7034:
#0: ffff8880381211e0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
#0: ffff8880381211e0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x20e/0x500 net/bluetooth/hci_core.c:2718
#1: ffff888038120428 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x506/0x1060 net/bluetooth/hci_sync.c:5300
2 locks held by syz.8.848/7318:
#0: ffff888041a6a0e0 (&type->s_umount_key#81){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffffffff8dbcc888 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x4f/0x1a0 fs/nfsd/nfssvc.c:633
2 locks held by syz.0.891/7508:
#0: ffff88803399e0e0 (&type->s_umount_key#81){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffffffff8dbcc888 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x4f/0x1a0 fs/nfsd/nfssvc.c:633
1 lock held by syz-executor/8583:
#0: ffffffff8eb566e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8eb566e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x80d/0xfb0 net/core/rtnetlink.c:6163
8 locks held by syz-executor/8600:
#0: ffff88807e388460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580
#1: ffff888033b2d488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1d8/0x520 fs/kernfs/file.c:343
#2: ffff888145b78918 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888145b78918 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x520 fs/kernfs/file.c:344
#3: ffffffff8e46a988 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd3/0x370 drivers/net/netdevsim/bus.c:209
#4: ffff88802a6980e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
#4: ffff88802a6980e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1099 [inline]
#4: ffff88802a6980e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb1/0x7c0 drivers/base/dd.c:1302
#5: ffff88802a6992f8 (&devlink->lock_key#2){+.+.}-{3:3}, at: nsim_drv_remove+0x54/0x170 drivers/net/netdevsim/dev.c:1678
#6: ffffffff8eb566e8 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x3b/0x150 drivers/net/netdevsim/netdev.c:381
#7: ffffffff8d933578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#7: ffffffff8d933578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962
1 lock held by syz-executor/8721:
#0: ffffffff8eb566e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8eb566e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x80d/0xfb0 net/core/rtnetlink.c:6163
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
<TASK>
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf0e/0xf50 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11 Comm: kworker/u4:1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:30 [inline]
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:52 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline]
RIP: 0010:unwind_next_frame+0x120e/0x1fd0 arch/x86/kernel/unwind_orc.c:448
Code: 29 e8 48 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 4c 8d 7c 45 00 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 75 27 49 63 07 4c 01 f8 49 8d 4f 04 4c 39 f0 48
RSP: 0018:ffffc900001075e0 EFLAGS: 00000a02
RAX: 1ffffffff1e19a86 RBX: ffffc90000107688 RCX: dffffc0000000000
RDX: ffffffff8f7aedca RSI: ffffffff8f0cd3c4 RDI: 0000000000000001
RBP: ffffffff8f0cd430 R08: 0000000000000021 R09: 000000000000000b
R10: dffffc0000000000 R11: fffff52000020edd R12: ffffffff8f0cd42c
R13: ffffffff8f0cd430 R14: ffffffff81004bbe R15: ffffffff8f0cd430
FS: 0000000000000000(0000) GS:ffff8880b8c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f30dd4b138 CR3: 000000007e0c0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
<TASK>
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1729 [inline]
slab_free_freelist_hook+0x133/0x1b0 mm/slub.c:1755
slab_free mm/slub.c:3687 [inline]
__kmem_cache_free+0xb6/0x200 mm/slub.c:3700
skb_free_head net/core/skbuff.c:762 [inline]
skb_release_data+0x5e9/0x7e0 net/core/skbuff.c:791
skb_release_all net/core/skbuff.c:856 [inline]
__kfree_skb net/core/skbuff.c:870 [inline]
consume_skb+0xa2/0x100 net/core/skbuff.c:1038
nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
nsim_dev_trap_report_work+0x71f/0xa80 drivers/net/netdevsim/dev.c:851
process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>