INFO: task syz.2.683:6588 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.683 state:D stack:26832 pid:6588 ppid:4280 flags:0x00004004
Call Trace:
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
nfsd_nrthreads+0x48/0xe0 fs/nfsd/nfssvc.c:280
write_threads+0x1ec/0x350 fs/nfsd/nfsctl.c:428
nfsctl_transaction_write+0x105/0x150 fs/nfsd/nfsctl.c:114
vfs_write+0x2dc/0x9a0 fs/read_write.c:582
ksys_write+0x14d/0x260 fs/read_write.c:637
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: 0033:0x7fdda699e019
RSP: 002b:00007fdda78ac028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fdda6c26090 RCX: 00007fdda699e019
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 00007fdda6a3500c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdda6c26128 R14: 00007fdda6c26090 R15: 00007ffd4e502058
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2e4f0 (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: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527
2 locks held by getty/4028:
#0: ffff88803091a098 (&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
3 locks held by syz.2.683/6578:
#0: ffff888027d68ae8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038
#1: ffff88802c584460 (sb_writers#20){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580
#2: ffffffff8cdcce08 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb3/0xb80 fs/nfsd/nfsctl.c:846
3 locks held by syz.2.683/6588:
#0: ffff8880298d8368 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038
#1: ffff88802c584460 (sb_writers#20){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580
#2: ffffffff8cdcce08 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nrthreads+0x48/0xe0 fs/nfsd/nfssvc.c:280
1 lock held by rm/9486:
#0: ffff8880b8e3ad18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x25/0x130 kernel/sched/core.c:538
=============================================
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 07/24/2026
Call Trace:
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
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4512 Comm: kworker/u4:11 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:kfence_alloc include/linux/kfence.h:126 [inline]
RIP: 0010:slab_alloc_node mm/slub.c:3283 [inline]
RIP: 0010:__kmem_cache_alloc_node+0x1e7/0x270 mm/slub.c:3398
Code: 5d 41 5e 41 5f 5d c3 e8 e7 f9 2d ff e9 74 ff ff ff e8 ad 8e 5d 08 48 c7 c7 d0 c1 c1 8c 4c 89 fe e8 1e f7 6a 02 e9 20 ff ff ff <83> 3d c2 4a ef 0a 00 0f 85 70 fe ff ff 4c 89 f7 48 8b 34 24 89 ea
RSP: 0018:ffffc90004a5f388 EFLAGS: 00000282
RAX: ffff888017441780 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000060 RDI: ffffffff8cc1f020
RBP: 0000000000000b20 R08: 0000000000000b20 R09: 0000000000000006
R10: 0000000000000005 R11: 0000000000000000 R12: ffffffff898c8d68
R13: 00000000ffffffff R14: ffff888017441780 R15: 0000000000000048
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3db7e8bff8 CR3: 000000002e8cd000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__do_kmalloc_node mm/slab_common.c:935 [inline]
__kmalloc+0xa3/0x240 mm/slab_common.c:949
kmalloc include/linux/slab.h:568 [inline]
kzalloc include/linux/slab.h:699 [inline]
cfg80211_inform_single_bss_frame_data net/wireless/scan.c:2481 [inline]
cfg80211_inform_bss_frame_data+0x728/0x1390 net/wireless/scan.c:2542
ieee80211_bss_info_update+0x6ef/0xbf0 net/mac80211/scan.c:190
ieee80211_rx_bss_info net/mac80211/ibss.c:1120 [inline]
ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1609 [inline]
ieee80211_ibss_rx_queued_mgmt+0x1931/0x2eb0 net/mac80211/ibss.c:1638
ieee80211_iface_process_skb net/mac80211/iface.c:1679 [inline]
ieee80211_iface_work+0x72c/0xc70 net/mac80211/iface.c:1733
cfg80211_wiphy_work+0x224/0x260 net/wireless/core.c:433
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