INFO: task syz-executor:5836 blocked for more than 143 seconds.
Tainted: G U 6.16.0-rc3-syzkaller-00057-g92ca6c498a5e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:23528 pid:5836 tgid:5836 ppid:1 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6878
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:747
nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596
nfsd_umount+0x48/0xe0 fs/nfsd/nfsctl.c:1386
deactivate_locked_super+0xc1/0x1a0 fs/super.c:474
deactivate_super fs/super.c:507 [inline]
deactivate_super+0xde/0x100 fs/super.c:503
cleanup_mnt+0x225/0x450 fs/namespace.c:1417
task_work_run+0x14d/0x240 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:114
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x3f6/0x490 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fba68f8fc57
RSP: 002b:00007ffc44509fe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fba69010925 RCX: 00007fba68f8fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc4450a0a0
RBP: 00007ffc4450a0a0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc4450b130
R13: 00007fba69010925 R14: 00000000000ba7c8 R15: 00007ffc4450b170
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5c47c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c47c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c47c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770
2 locks held by syz-executor/5836:
#0: ffff88804e6a60e0 (&type->s_umount_key#52){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88804e6a60e0 (&type->s_umount_key#52){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88804e6a60e0 (&type->s_umount_key#52){++++}-{4:4}, at: deactivate_super fs/super.c:506 [inline]
#0: ffff88804e6a60e0 (&type->s_umount_key#52){++++}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:503
#1: ffffffff8e9ddd68 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596
2 locks held by kworker/u10:4/11130:
#0: ffff88801f7bb948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc90003847d10 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
5 locks held by kworker/u10:5/11143:
#0: ffff88801c6fe148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc90003f4fd10 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
#2: ffffffff90338250 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x890 net/core/net_namespace.c:662
#3: ffffffff9034e2a8 (rtnl_mutex){+.+.}-{4:4}, at: caif_exit_net+0x64/0x3c0 net/caif/caif_dev.c:528
#4: ffff88805b2a8a80 (&caifn->caifdevs.lock){+.+.}-{4:4}, at: caif_exit_net+0x7b/0x3c0 net/caif/caif_dev.c:529
2 locks held by getty/14474:
#0: ffff88814c96e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900039fd2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
2 locks held by syz.1.2158/16877:
#0: ffffffff903f2ab0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e9ddd68 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1629
2 locks held by udevd/16880:
2 locks held by syz.6.2687/19557:
#0: ffffffff8e4925e8 (sched_core_mutex){+.+.}-{4:4}, at: sched_core_get+0x3f/0xa0 kernel/sched/core.c:452
#1: ffffffff8e5cfdb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:336
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U 6.16.0-rc3-syzkaller-00057-g92ca6c498a5e #0 PREEMPT(full)
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xf70/0x12c0 kernel/hung_task.c:470
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
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: 11108 Comm: kworker/u10:3 Tainted: G U 6.16.0-rc3-syzkaller-00057-g92ca6c498a5e #0 PREEMPT(full)
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:mark_lock+0x22/0x610 kernel/locking/lockdep.c:4717
Code: 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 f0 48 83 ec 70 65 48 8b 05 eb 27 34 12 48 89 44 24 68 <31> c0 83 fa 09 0f 87 8d 00 00 00 49 89 ff 49 89 f4 89 d3 83 fa 08
RSP: 0018:ffffc90000007800 EFLAGS: 00000086
RAX: b004d8c053820a00 RBX: 0000000000000005 RCX: ffffffff95d37608
RDX: 0000000000000008 RSI: ffff88801f7d0bb8 RDI: ffff88801f7d0000
RBP: ffffc90000007898 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000000c8 R11: 0000000000000001 R12: ffff88801f7d0af0
R13: ffff88801f7d0bb8 R14: 0000000000000005 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888124760000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b303a2ff8 CR3: 000000007f394000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
mark_usage kernel/locking/lockdep.c:4677 [inline]
__lock_acquire+0x3e9/0x1c90 kernel/locking/lockdep.c:5194
lock_acquire kernel/locking/lockdep.c:5871 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2381 [inline]
slab_free_after_rcu_debug+0x10d/0x340 mm/slub.c:4693
rcu_do_batch kernel/rcu/tree.c:2576 [inline]
rcu_core+0x799/0x14e0 kernel/rcu/tree.c:2832
handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
do_softirq kernel/softirq.c:480 [inline]
do_softirq+0xb2/0xf0 kernel/softirq.c:467
__local_bh_enable_ip+0x100/0x120 kernel/softirq.c:407
spin_unlock_bh include/linux/spinlock.h:396 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline]
nsim_dev_trap_report_work+0x8b5/0xcf0 drivers/net/netdevsim/dev.c:851
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3321 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245