INFO: task syz.2.1911:11240 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.2.1911 state:D stack:27840 pid:11240 tgid:11237 ppid:8895 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f9/0x5500 kernel/sched/core.c:7197
__schedule_loop kernel/sched/core.c:7276 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7291
cgroup_lock_and_drain_offline+0x516/0x650 kernel/cgroup/cgroup.c:3248
cgroup_kn_lock_live+0x120/0x230 kernel/cgroup/cgroup.c:1699
cgroup_subtree_control_write+0x4b3/0x10a0 kernel/cgroup/cgroup.c:3550
cgroup_file_write+0x331/0x8f0 kernel/cgroup/cgroup.c:4289
kernfs_fop_write_iter+0x3b0/0x540 fs/kernfs/file.c:352
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x629/0xba0 fs/read_write.c:688
ksys_write+0x156/0x270 fs/read_write.c:740
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fedb545ce59
RSP: 002b:00007fedb36b6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fedb56d5fa0 RCX: 00007fedb545ce59
RDX: 0000000000000006 RSI: 0000200000000080 RDI: 0000000000000006
RBP: 00007fedb54f2d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fedb56d6038 R14: 00007fedb56d5fa0 R15: 00007ffde178bde8
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8e1ca240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e1ca240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e1ca240 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777
2 locks held by getty/5366:
#0: ffff8880326140a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
4 locks held by kworker/1:7/6572:
#0: ffff888022ab5938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3293
#1: ffffc90007d77c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3294
#2: ffff88802ad6e210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1038 [inline]
#2: ffff88802ad6e210 (&dev->mutex){....}-{4:4}, at: hub_event+0x17c/0x4f60 drivers/usb/core/hub.c:5899
#3: ffff88801beab348 (&root->kernfs_supers_rwsem){++++}-{4:4}, at: kernfs_remove_by_name_ns+0x3f/0x140 fs/kernfs/dir.c:1792
3 locks held by syz.2.1911/11240:
#0: ffff8880116dfd28 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1260
#1: ffff888034826480 (sb_writers#9){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#1: ffff888034826480 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684
#2: ffff88805dcb3c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
1 lock held by syz.7.2453/13228:
#0: ffffffff8e1ca240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e1ca240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e1ca240 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
#0: ffffffff8e1ca240 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa6/0x2550 arch/x86/kernel/unwind_orc.c:495
2 locks held by syz.7.2479/13328:
#0: ffff8880418944b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline]
#0: ffff8880418944b0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x237/0x4f0 mm/util.c:579
#1: ffff8880365c6480 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2272 [inline]
#1: ffff8880365c6480 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x286/0x460 fs/ext4/file.c:840
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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: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+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x389/0x470 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 67 Comm: kworker/u8:4 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker
RIP: 0010:fsqr lib/crypto/x86/curve25519.h:667 [inline]
RIP: 0010:fsquare_times lib/crypto/x86/curve25519.h:1115 [inline]
RIP: 0010:finv lib/crypto/x86/curve25519.h:1146 [inline]
RIP: 0010:encode_point+0x70a0/0x84b0 lib/crypto/x86/curve25519.h:1212
Code: 01 00 00 48 89 74 24 18 48 8d b4 24 e0 00 00 00 48 89 f7 4c 8b 64 24 18 48 8b 17 c4 62 bb f6 77 08 45 31 ff c4 62 b3 f6 57 10 <66> 4d 0f 38 f6 ce c4 e2 fb f6 4f 18 66 4c 0f 38 f6 d0 48 8b 57 18
RSP: 0018:ffffc9000152f140 EFLAGS: 00000246
RAX: ffffffff84ba9c3d RBX: 0000000000000024 RCX: ffff88801df7dc40
RDX: 5108cb67c25c380e RSI: ffffc9000152f220 RDI: ffffc9000152f220
RBP: ffffc9000152f390 R08: 829da7bb20cc139e R09: 5e1baf3bc38b8dde
R10: 38f744d83337da4b R11: 06a5dcf604dda3d8 R12: ffffc9000152f2a0
R13: 0000000000000009 R14: 2751806139aaf94c R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125cab000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe295e25690 CR3: 000000002a266000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
curve25519_ever64 lib/crypto/x86/curve25519.h:1248 [inline]
curve25519_arch lib/crypto/x86/curve25519.h:1594 [inline]
curve25519+0x5137/0x51d0 lib/crypto/curve25519.c:44
mix_dh drivers/net/wireguard/noise.c:411 [inline]
wg_noise_handshake_create_initiation+0x285/0x830 drivers/net/wireguard/noise.c:550
wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:34 [inline]
wg_packet_handshake_send_worker+0x18d/0x350 drivers/net/wireguard/send.c:51
process_one_work+0x98b/0x1630 kernel/workqueue.c:3318
process_scheduled_works kernel/workqueue.c:3401 [inline]
worker_thread+0xb49/0x1140 kernel/workqueue.c:3482
kthread+0x389/0x470 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