INFO: task syz.3.522:8249 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.522 state:D stack:26328 pid:8249 tgid:8241 ppid:5615 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7376 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7433 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7c1/0x1550 kernel/locking/mutex.c:821 nfsd_nl_version_set_doit+0xcd/0x7a0 fs/nfsd/nfsctl.c:1844 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2572 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7bd/0x940 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1916 sock_sendmsg_nosec+0x14e/0x190 net/socket.c:800 __sock_sendmsg net/socket.c:818 [inline] sock_write_iter+0x2de/0x3e0 net/socket.c:1269 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1f7039e159 RSP: 002b:00007f1f7122a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f1f70626180 RCX: 00007f1f7039e159 RDX: 000000000000002c RSI: 0000200000000000 RDI: 0000000000000008 RBP: 00007f1f7043506b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1f70626218 R14: 00007f1f70626180 R15: 00007ffea54aedd8 Showing all locks held in the system: locks held by kworker/u8:1/13: 4, last CPU#1: #0: ffff88807772e940 ((wq_completion)krds_cp_wq#1/0){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88807772e940 ((wq_completion)krds_cp_wq#1/0){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88807772e940 ((wq_completion)krds_cp_wq#1/0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff88807772e940 ((wq_completion)krds_cp_wq#1/0){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc90000127c40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90000127c40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90000127c40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc90000127c40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #2: ffff88801eb85280 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920 net/rds/tcp_connect.c:118 #3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: __inet_dev_addr_type+0x159/0x560 net/ipv4/fib_frontend.c:241 locks held by khungtaskd/32: 1, last CPU#1: #0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871 locks held by kworker/u8:7/1096: 4, last CPU#0: #0: ffff888076ce4940 ((wq_completion)wg-kex-wg2#5){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff888076ce4940 ((wq_completion)wg-kex-wg2#5){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff888076ce4940 ((wq_completion)wg-kex-wg2#5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff888076ce4940 ((wq_completion)wg-kex-wg2#5){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc900052efc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc900052efc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc900052efc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc900052efc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #2: ffff888033de9440 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x12e/0x810 drivers/net/wireguard/noise.c:529 #3: ffff88802d28e640 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x13f/0x810 drivers/net/wireguard/noise.c:530 locks held by kworker/u8:9/1167: 4, last CPU#0: #0: ffff888076ce6140 ((wq_completion)wg-kex-wg0#7){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff888076ce6140 ((wq_completion)wg-kex-wg0#7){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff888076ce6140 ((wq_completion)wg-kex-wg0#7){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff888076ce6140 ((wq_completion)wg-kex-wg0#7){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc9000556fc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc9000556fc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc9000556fc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc9000556fc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #2: ffffffff8ed5c900 (rcu_read_lock_bh){....}-{1:3}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:677 #3: ffff8880b8624408 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933 locks held by klogd/4972: 2, last CPU#1: #0: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:198 [inline] #0: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60 include/linux/srcu.h:305 #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: page_ext_get+0x22/0x2e0 mm/page_ext.c:522 locks held by getty/5374: 2, on CPU#1: #0: ffff8880357630a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 locks held by syz-executor/5617: 2, last CPU#0: #0: ffff888031a28460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff88802b51ef18 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff88802b51ef18 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff88802b51ef18 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff88802b51ef18 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: filename_rmdir+0x1cd/0x520 fs/namei.c:5565 locks held by syz.2.197/6684: 2, on CPU#0: #0: ffffffff902b8ee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8f09f7c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x53d/0x1ab0 fs/nfsd/nfsctl.c:2057 locks held by syz.3.522/8249: 2, on CPU#0: #0: ffffffff902b8ee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8f09f7c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_set_doit+0xcd/0x7a0 fs/nfsd/nfsctl.c:1844 locks held by syz-executor/8846: 4, last CPU#1: #0: ffffffff8ee36650 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1542 [inline] #0: ffffffff8ee36650 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x10a/0x480 kernel/fork.c:1595 #1: ffff88803635e540 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline] #1: ffff88803635e540 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x195/0x1dc0 mm/mmap.c:1716 #2: ffff888077647180 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:552 [inline] #2: ffff888077647180 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x221/0x1dc0 mm/mmap.c:1723 #3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290 locks held by syz.1.1846/14123: 2, last CPU#1: #0: ffff88804c438f80 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline] #0: ffff88804c438f80 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x1a4/0x9f0 mm/mmap.c:1299 #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290 locks held by dhcpcd-run-hook/14167: 4, last CPU#0: #0: ffff888055aafe48 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: do_fault_around mm/memory.c:5957 [inline] #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: do_read_fault mm/memory.c:5991 [inline] #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: do_fault mm/memory.c:6134 [inline] #1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: do_pte_missing+0x140c/0x34b0 mm/memory.c:4700 #2: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #2: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #2: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: filemap_map_pages+0x1d1/0x2170 mm/filemap.c:3921 #3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123 nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66 trigger_all_cpu_backtrace include/linux/nmi.h:164 [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+0x38b/0x480 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: 6841 Comm: kworker/0:17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Workqueue: 0x0 (events) RIP: 0010:__remove_hrtimer+0x129/0x3e0 kernel/time/hrtimer.c:1183 Code: 00 4d 85 ed 0f 84 8a 00 00 00 e8 12 61 13 00 eb 05 e8 0b 61 13 00 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d e9 08 5d 34 0a cc <4d> 8d 67 08 4c 89 e0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 f4 01 00 RSP: 0018:ffffc90000007d78 EFLAGS: 00000046 RAX: 1ffff110170c5000 RBX: 1ffff11009d17667 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88804e8bb328 RBP: dffffc0000000000 R08: ffff88804e8bb327 R09: 0000000000000000 R10: ffff88804e8bb318 R11: ffffed1009d17665 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88804e8bb300 R15: ffff8880b8628440 FS: 0000000000000000(0000) GS:ffff888124cda000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3667b3c9e0 CR3: 000000005f1e4000 CR4: 00000000003526f0 Call Trace: __run_hrtimer kernel/time/hrtimer.c:2054 [inline] __hrtimer_run_queues+0x295/0xa10 kernel/time/hrtimer.c:2131 hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2250 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:finish_task_switch+0x413/0xc60 kernel/sched/core.c:5384 Code: 04 00 00 41 c7 84 24 20 0e 00 00 00 00 00 00 0f 1f 44 00 00 49 83 c4 48 4c 89 e7 e8 c7 8f 52 0a e8 b2 2d 3a 00 fb 4c 8b 65 c8 <49> 8d bc 24 18 17 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 RSP: 0018:ffffc90004f2fa60 EFLAGS: 00000206 RAX: 000000000000c43f RBX: ffff8880b863c8e0 RCX: 8000000000000001 RDX: 0000000000000000 RSI: ffffffff8e4049bd RDI: ffffffff8c6dad80 RBP: ffffc90004f2fab0 R08: ffffffff9079a07f R09: 1ffffffff20f340f R10: dffffc0000000000 R11: fffffbfff20f3410 R12: ffff888028b81f40 R13: ffff8880b863c8a8 R14: dffffc0000000000 R15: 1ffff110170c791c context_switch kernel/sched/core.c:5536 [inline] __schedule+0x17e3/0x58f0 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7376 worker_thread+0xc12/0xfb0 kernel/workqueue.c:3575 kthread+0x38b/0x480 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