INFO: task syz.3.15179:5652 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.3.15179 state:D stack:26520 pid:5652 tgid:5651 ppid:5614 task_flags:0x400040 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] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7572 rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1667 __rt_mutex_slowlock kernel/locking/rtmutex.c:1744 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1784 [inline] rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1824 __rt_mutex_lock kernel/locking/rtmutex.c:1839 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:541 [inline] mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:559 nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1744 genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2551 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x780/0x920 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1895 sock_sendmsg_nosec+0x112/0x150 net/socket.c:797 __sock_sendmsg net/socket.c:812 [inline] ____sys_sendmsg+0x55c/0x870 net/socket.c:2716 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2770 __sys_sendmsg net/socket.c:2802 [inline] __do_sys_sendmsg net/socket.c:2807 [inline] __se_sys_sendmsg net/socket.c:2805 [inline] __x64_sys_sendmsg+0x1c3/0x2a0 net/socket.c:2805 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: 0033:0x7f49aa20ce59 RSP: 002b:00007f49a8466028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f49aa485fa0 RCX: 00007f49aa20ce59 RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000003 RBP: 00007f49aa2a2d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f49aa486038 R14: 00007f49aa485fa0 R15: 00007ffdab05aa98 Showing all locks held in the system: 11 locks held by kworker/u8:1/13: #0: ffff8880368d5938 ((wq_completion)wg-kex-wg1#5){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3281 #1: ffffc90000127c40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3282 #2: ffffffff8e05f380 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 #3: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 #4: ffff88805a031798 (&peer->endpoint_lock){++..}-{3:3}, at: read_lock_bh include/linux/rwlock_rt.h:45 [inline] #4: ffff88805a031798 (&peer->endpoint_lock){++..}-{3:3}, at: wg_socket_send_skb_to_peer+0x6e/0x200 drivers/net/wireguard/socket.c:172 #5: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #5: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #5: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rt_read_lock+0x277/0x4b0 kernel/locking/spinlock_rt.c:234 #6: ffffffff8e05f380 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 #7: ffffffff8e1c82a0 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #7: ffffffff8e1c82a0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:891 [inline] #7: ffffffff8e1c82a0 (rcu_read_lock_bh){....}-{1:3}, at: send6+0x255/0x910 drivers/net/wireguard/socket.c:118 #8: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #8: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #8: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: ip6_dst_lookup_tail+0x226/0x15a0 net/ipv6/ip6_output.c:1161 #9: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #9: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #9: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: ip6_dst_lookup_tail+0x226/0x15a0 net/ipv6/ip6_output.c:1161 #10: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #10: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #10: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: ipv6_dev_get_saddr+0x160/0xbb0 net/ipv6/addrconf.c:1836 1 lock held by khungtaskd/39: #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777 2 locks held by getty/5370: #0: ffff8880362120a0 (&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 2 locks held by syz.2.14227/3452: #0: ffffffff8f6024c0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8e4ec158 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x13e/0x1630 fs/nfsd/nfsctl.c:1954 2 locks held by syz.3.15179/5652: #0: ffffffff8f6024c0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8e4ec158 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1744 1 lock held by syz.6.16668/9183: #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1181 [inline] #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa6/0x2550 arch/x86/kernel/unwind_orc.c:495 6 locks held by dhcpcd-run-hook/9332: #0: ffff888039a1d588 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #1: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #1: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: do_fault_around mm/memory.c:5868 [inline] #1: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: do_read_fault mm/memory.c:5902 [inline] #1: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: do_fault mm/memory.c:6045 [inline] #1: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: do_pte_missing+0x12b5/0x2940 mm/memory.c:4566 #2: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #2: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #2: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: filemap_map_pages+0x201/0x1d10 mm/filemap.c:3899 #3: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #3: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #3: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:290 #4: ffff88801ab9fd18 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #4: ffff88801ab9fd18 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404 #5: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #5: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #5: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #5: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 39 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+0x388/0x470 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 9332 Comm: dhcpcd-run-hook 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 RIP: 0010:sync_rcu_exp_done kernel/rcu/tree_exp.h:164 [inline] RIP: 0010:rcu_preempt_deferred_qs_irqrestore+0x3c9/0xc60 kernel/rcu/tree_plugin.h:539 Code: 85 c0 0f 84 3c 06 00 00 49 8d 9f e0 00 00 00 48 89 d8 48 c1 e8 03 48 89 44 24 08 42 80 3c 28 00 74 08 48 89 df e8 27 05 84 00 <48> 83 3b 00 74 0a c7 44 24 14 00 00 00 00 eb 2f 4d 8d 6f 78 4c 89 RSP: 0018:ffffc90005c3fb08 EFLAGS: 00000046 RAX: 1ffffffff1c39bb4 RBX: ffffffff8e1cdda0 RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8d9ab4ae RDI: ffffffff8baa6d60 RBP: ffff88801e3bbd80 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000b87f50 R12: ffffffff8e1cdd79 R13: dffffc0000000000 R14: ffffffff8e1cdd00 R15: ffffffff8e1cdcc0 FS: 00007f3db2ab7c80(0000) GS:ffff888125dc7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3db2ba8190 CR3: 000000005d266000 CR4: 00000000003526f0 Call Trace: __rcu_read_unlock+0x83/0xe0 kernel/rcu/tree_plugin.h:438 rcu_read_unlock include/linux/rcupdate.h:871 [inline] do_fault_around mm/memory.c:5872 [inline] do_read_fault mm/memory.c:5902 [inline] do_fault mm/memory.c:6045 [inline] do_pte_missing+0x16d7/0x2940 mm/memory.c:4566 handle_pte_fault mm/memory.c:6430 [inline] __handle_mm_fault mm/memory.c:6568 [inline] handle_mm_fault+0xdb5/0x14c0 mm/memory.c:6737 do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0033:0x7f3db2ba8190 Code: 68 04 00 00 00 e9 90 fe ff ff ff 25 d2 8a 1a 00 68 27 00 00 00 e9 80 fe ff ff ff 25 ca 8a 1a 00 68 26 00 00 00 e9 70 fe ff ff 25 c2 8a 1a 00 68 25 00 00 00 e9 60 fe ff ff ff 25 ba 8a 1a 00 RSP: 002b:00007ffd62e60878 EFLAGS: 00010202 RAX: 00007ffd62e60e60 RBX: 00007ffd62e60d80 RCX: 0000000000000000 RDX: 00007ffd62e60e40 RSI: 0000000000000025 RDI: 00007f3db2e0086a RBP: 00007ffd62e60f30 R08: 000055faa874aea2 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000201 R13: 00007ffd62e60e40 R14: 0000000000000001 R15: 00007f3db2e0086a