INFO: task syz.2.1965:16463 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.2.1965 state:D stack:24664 pid:16463 tgid:16463 ppid:15391 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776
nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:575
nfsd_umount+0x41/0x60 fs/nfsd/nfsctl.c:1347
deactivate_locked_super+0xbc/0x130 fs/super.c:474
put_fs_context+0x93/0xb00 fs/fs_context.c:517
fscontext_release+0x62/0x80 fs/fsopen.c:79
__fput+0x44c/0xa70 fs/file_table.c:468
task_work_run+0x1d4/0x260 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
exit_to_user_mode_loop+0xef/0x4e0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2c1/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6addf8f749
RSP: 002b:00007ffdc05a4268 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f6ade1e7da0 RCX: 00007f6addf8f749
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f6ade1e7da0 R08: 0000000000001130 R09: 0000000bc05a455f
R10: 00000000003fecac R11: 0000000000000246 R12: 000000000013b5c0
R13: 00007f6ade1e6270 R14: ffffffffffffffff R15: 00007ffdc05a4380
Showing all locks held in the system:
1 lock held by khungtaskd/32:
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:10/1336:
2 locks held by getty/5582:
#0: ffff8880347450a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211
6 locks held by kworker/u8:17/6007:
#0: ffff88801aa9f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88801aa9f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc90004f9fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90004f9fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8f304f90 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7a0 net/core/net_namespace.c:670
#3: ffff88805d3f10e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#3: ffff88805d3f10e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
#3: ffff88805d3f10e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506
#4: ffff88805d3f5250 (&devlink->lock_key#49){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline]
#4: ffff88805d3f5250 (&devlink->lock_key#49){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
#4: ffff88805d3f5250 (&devlink->lock_key#49){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506
#5: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1049 [inline]
#5: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: nsim_create+0x800/0x1050 drivers/net/netdevsim/netdev.c:1143
3 locks held by kworker/u8:23/6277:
#0: ffff88813ff29948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813ff29948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc9000b8f7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000b8f7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
3 locks held by kworker/u8:25/7339:
#0: ffff88814cd39148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88814cd39148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc9000b807bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000b807bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4194
1 lock held by syz-executor/15149:
2 locks held by syz.0.1937/16353:
#0: ffffffff8f379cb0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e237b88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2cb/0x960 fs/nfsd/nfsctl.c:1590
2 locks held by syz.2.1965/16463:
#0: ffff888079cce0e0 (&type->s_umount_key#130){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff888079cce0e0 (&type->s_umount_key#130){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff888079cce0e0 (&type->s_umount_key#130){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffffffff8e237b88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:575
1 lock held by syz-executor/17497:
#0: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978
2 locks held by syz-executor/17565:
#0: ffffffff8f826290 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8f826290 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8f826290 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
3 locks held by syz-executor/17603:
#0: ffffffff8ea95ae8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8ea95ae8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8ea95ae8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f312048 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
#2: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#2: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x36e/0x6e0 kernel/rcu/tree_exp.h:956
2 locks held by syz.5.2260/17746:
#0: ffffffff8f315428 (bpf_dispatcher_xdp.mutex){+.+.}-{4:4}, at: bpf_dispatcher_change_prog+0x9c/0xc90 kernel/bpf/dispatcher.c:146
#1: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x36e/0x6e0 kernel/rcu/tree_exp.h:956
=============================================
NMI backtrace for cpu 1
CPU: 1 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 10/25/2025
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:160 [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+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17746 Comm: syz.5.2260 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:mark_usage kernel/locking/lockdep.c:4620 [inline]
RIP: 0010:__lock_acquire+0x5f3/0x2cf0 kernel/locking/lockdep.c:5191
Code: 00 0f 8c 0b ff ff ff 44 89 e0 38 04 24 76 16 e8 93 9e ec 02 85 c0 74 0d 83 3d dc 5d e4 0d 00 0f 84 0a 08 00 00 83 7c 24 10 00 <0f> 84 a8 00 00 00 41 8b 45 20 66 85 c0 0f 88 8c 00 00 00 65 8b 0d
RSP: 0018:ffffc900000076d0 EFLAGS: 00000046
RAX: 00000000ffffff03 RBX: ffff888026fd4878 RCX: 0000000000000001
RDX: 0000000000000003 RSI: 0000000000002000 RDI: 0000000000000000
RBP: ffff888026fd4858 R08: ffffffff8173fd65 R09: ffffffff8df41aa0
R10: dffffc0000000000 R11: ffffffff81acf3d0 R12: 00000000ffffff03
R13: ffff888026fd4858 R14: ffff888026fd3d00 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125e1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9c0ff62f40 CR3: 000000000dd3a000 CR4: 0000000000350ef0
Call Trace:
lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xc2/0x23d0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2540 [inline]
slab_free mm/slub.c:6670 [inline]
kfree+0x1c0/0x660 mm/slub.c:6878
slab_free_after_rcu_debug+0x5d/0x260 mm/slub.c:6716
rcu_do_batch kernel/rcu/tree.c:2605 [inline]
rcu_core+0xc8e/0x1720 kernel/rcu/tree.c:2857
handle_softirqs+0x22b/0x7c0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x60/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__unwind_start+0x39/0x760 arch/x86/kernel/unwind_orc.c:702
Code: 83 ec 28 48 89 4c 24 10 49 89 d4 49 89 f5 48 89 fb 49 be 00 00 00 00 00 fc ff df ba 60 00 00 00 31 f6 e8 3a f5 b2 00 4c 89 f2 <4c> 8d 73 28 4d 89 f7 49 c1 ef 03 41 80 3c 17 00 74 12 4c 89 f7 e8
RSP: 0018:ffffc900044cede8 EFLAGS: 00000202
RAX: ffffc900044cee48 RBX: ffffc900044cee48 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffc900044ceea8
RBP: ffffc900044ceed0 R08: ffffc900044ceea7 R09: ffffc900044cee48
R10: dffffc0000000000 R11: fffff52000899dd5 R12: 0000000000000000
R13: ffff888026fd3d00 R14: dffffc0000000000 R15: 0000000000000000
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 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_unref_folios+0xdb3/0x14f0 mm/page_alloc.c:3000
folios_put_refs+0x584/0x670 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x1490 mm/shmem.c:1137
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x26e/0xa70 mm/shmem.c:1379
evict+0x5f4/0xae0 fs/inode.c:837
__dentry_kill+0x209/0x660 fs/dcache.c:670
finish_dput+0xc9/0x480 fs/dcache.c:879
__fput+0x68e/0xa70 fs/file_table.c:476
task_work_run+0x1d4/0x260 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x694/0x22f0 kernel/exit.c:971
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x87/0x4e0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2c1/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8081f8f749
Code: Unable to access opcode bytes at 0x7f8081f8f71f.
RSP: 002b:00007f8082e7c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: 0000000000000000 RBX: 00007f80821e5fa0 RCX: 00007f8081f8f749
RDX: 0000000000000050 RSI: 0000200000000380 RDI: 000000000000000a
RBP: 00007f8082013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f80821e6038 R14: 00007f80821e5fa0 R15: 00007fffba6f3028