INFO: task syz.5.4637:18417 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.4637 state:D stack:28424 pid:18417 tgid:18416 ppid:5631 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
write_versions+0x95/0xe30 fs/nfsd/nfsctl.c:701
nfsctl_transaction_write+0x10f/0x160 fs/nfsd/nfsctl.c:112
vfs_write+0x296/0xba0 fs/read_write.c:685
ksys_write+0x150/0x270 fs/read_write.c:739
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: 0033:0x7f0f58d9de99
RSP: 002b:00007f0f59bee028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f0f59025fa0 RCX: 00007f0f58d9de99
RDX: 0000000000000001 RSI: 0000200000000240 RDI: 0000000000000003
RBP: 00007f0f58e33eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0f59026038 R14: 00007f0f59025fa0 R15: 00007ffd8555fee8
Showing all locks held in the system:
1 lock held by khungtaskd/32:
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:4/58:
8 locks held by kworker/u8:6/321:
#0: ffff8880b863b160 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667
#1: ffff8880b8624440 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933
#2: ffff88807a27e258 (&devlink->lock_key#17){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40 drivers/net/netdevsim/dev.c:909
#3: ffff888046729700 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x13f/0x810 drivers/net/wireguard/noise.c:530
#4: ffff88804b150018 (&table->lock#2){+...}-{3:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#4: ffff88804b150018 (&table->lock#2){+...}-{3:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#4: ffff88804b150018 (&table->lock#2){+...}-{3:3}, at: l3mdev_l3_out include/net/l3mdev.h:212 [inline]
#4: ffff88804b150018 (&table->lock#2){+...}-{3:3}, at: l3mdev_ip6_out include/net/l3mdev.h:236 [inline]
#4: ffff88804b150018 (&table->lock#2){+...}-{3:3}, at: __ip6_local_out+0x15c/0x940 net/ipv6/output_core.c:110
#5: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#5: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#5: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
#6: ffffffff9aa7ed30 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xb7/0x420 lib/debugobjects.c:873
#7: ffffffff9a7cb748 (&____s->seqcount#2){----}-{0:0}, at: ktime_get+0x45/0x220 kernel/time/timekeeping.c:971
2 locks held by getty/5377:
#0: ffff888035de90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
2 locks held by kworker/u9:2/5634:
#0: ffff888022bcc940 ((wq_completion)nbd2-recv){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff888022bcc940 ((wq_completion)nbd2-recv){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc9000419fc40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc9000419fc40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
2 locks held by kworker/1:4/5636:
#0: ffff88801b02b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88801b02b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc900041bfc40 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc900041bfc40 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
2 locks held by kworker/u9:4/5641:
#0: ffff888022bcc940 ((wq_completion)nbd2-recv){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff888022bcc940 ((wq_completion)nbd2-recv){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc900041ffc40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc900041ffc40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
2 locks held by kworker/u9:7/5650:
#0: ffff888022bcc940 ((wq_completion)nbd2-recv){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff888022bcc940 ((wq_completion)nbd2-recv){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc9000428fc40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc9000428fc40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
2 locks held by syz-executor/17974:
#0: ffff888046c1e0d8 (&type->s_umount_key#122){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888046c1e0d8 (&type->s_umount_key#122){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff888046c1e0d8 (&type->s_umount_key#122){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:509
#1: ffffffff8ee8e620 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:576
3 locks held by syz.4.4575/18205:
#0: ffff88807ef89270 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259
#1: ffff888062bc4450 (sb_writers#36){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#1: ffff888062bc4450 (sb_writers#36){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#2: ffffffff8ee8e620 (nfsd_mutex){+.+.}-{4:4}, at: write_ports+0xb5/0xd10 fs/nfsd/nfsctl.c:860
3 locks held by syz.5.4637/18417:
#0: ffff88807f71fb30 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259
#1: ffff888053398450 (sb_writers#36){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#1: ffff888053398450 (sb_writers#36){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#2: ffffffff8ee8e620 (nfsd_mutex){+.+.}-{4:4}, at: write_versions+0x95/0xe30 fs/nfsd/nfsctl.c:701
3 locks held by syz.2.4803/19127:
#0: ffff88807ef8b270 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259
#1: ffff888025ea8450 (sb_writers#36){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#1: ffff888025ea8450 (sb_writers#36){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#2: ffffffff8ee8e620 (nfsd_mutex){+.+.}-{4:4}, at: write_versions+0x95/0xe30 fs/nfsd/nfsctl.c:701
2 locks held by syz-executor/19496:
#0: ffff8880792780d8 (&type->s_umount_key#122){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880792780d8 (&type->s_umount_key#122){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff8880792780d8 (&type->s_umount_key#122){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:509
#1: ffffffff8ee8e620 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:576
2 locks held by syz-executor/20313:
#0: ffff88808782cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:497 [inline]
#0: ffff88808782cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x22a/0x5b0 net/bluetooth/hci_core.c:2678
#1: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
3 locks held by syz.8.5475/21429:
#0: ffff888033f85eb0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259
#1: ffff8880522d6450 (sb_writers#36){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#1: ffff8880522d6450 (sb_writers#36){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#2: ffffffff8ee8e620 (nfsd_mutex){+.+.}-{4:4}, at: nfsd4_write_time+0xb1/0x6c0 fs/nfsd/nfsctl.c:963
1 lock held by syz.1.5523/21578:
#0: ffff888046c1e0d8 (&type->s_umount_key#122){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888046c1e0d8 (&type->s_umount_key#122){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
7 locks held by syz-executor/21898:
#0: ffff888036464450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#0: ffff888036464450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#1: ffff88808f616480 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d8/0x540 fs/kernfs/file.c:336
#2: ffff888028df0698 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888028df0698 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22b/0x540 fs/kernfs/file.c:337
#3: ffffffff8f8a96a0 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234
#4: ffff888055fc9128 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#4: ffff888055fc9128 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline]
#4: ffff888055fc9128 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb9/0x880 drivers/base/dd.c:1369
#5: ffff888055fc8258 (&devlink->lock_key#12){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x170 drivers/net/netdevsim/dev.c:1799
#6: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#6: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
3 locks held by syz.9.5679/21997:
#0: ffff88802c0c3270 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259
#1: ffff88804e6b4450 (sb_writers#36){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#1: ffff88804e6b4450 (sb_writers#36){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#2: ffffffff8ee8e620 (nfsd_mutex){+.+.}-{4:4}, at: nfsd4_write_time+0xb1/0x6c0 fs/nfsd/nfsctl.c:963
=============================================
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 07/16/2026
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 21784 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:check_preemption_disabled+0x1/0xe0 lib/smp_processor_id.c:13
Code: 20 dc 4b 8c 48 c7 c6 60 dc 4b 8c eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 <41> 57 41 56 53 65 8b 05 f7 0d 9c 07 65 8b 0d ec 0d 9c 07 f7 c1 ff
RSP: 0018:ffffc9000d6df4f0 EFLAGS: 00000282
RAX: 0000000000000001 RBX: ffffffff81afced4 RCX: ffff88807c9ebe00
RDX: 000000005a44979c RSI: ffffffff8c4bdc60 RDI: ffffffff8c4bdc20
RBP: 1ffff92001adbec0 R08: ffffffff8177827f R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8eb59c60 R12: dffffc0000000000
R13: ffffffff8177827f R14: ffffc9000d6df5c8 R15: 1ffff92001adbeb9
FS: 0000000000000000(0000) GS:ffff88812504e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055abfb730ee8 CR3: 000000003a22b000 CR4: 0000000000350ef0
Call Trace:
rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:752
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0xbe/0x2550 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
free_pages_prepare+0x960/0xa60 mm/page_alloc.c:1451
__free_contig_range_common+0x174/0x340 mm/page_alloc.c:6897
__free_contig_range mm/page_alloc.c:6942 [inline]
free_pages_bulk+0x48/0x120 mm/page_alloc.c:5257
vm_area_free_pages mm/vmalloc.c:3439 [inline]
vfree+0x224/0x4a0 mm/vmalloc.c:3488
kcov_put kernel/kcov.c:449 [inline]
kcov_close+0x28/0x50 kernel/kcov.c:554
__fput+0x418/0xa50 fs/file_table.c:512
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:1009
do_group_exit+0x22d/0x2f0 kernel/exit.c:1152
get_signal+0x121b/0x12c0 kernel/signal.c:3046
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x104/0x730 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe18f15e6ce
Code: Unable to access opcode bytes at 0x7fe18f15e6a4.
RSP: 002b:00007ffc6341df48 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: 0000000000000040 RBX: 0000555573f2b500 RCX: 00007fe18f15e6ce
RDX: 0000000000000040 RSI: 00007fe18ff54670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffc6341dfc4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fe18ff54670 R15: 0000000000000000