INFO: task syz.0.1830:12206 blocked for more than 143 seconds. Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1830 state:D stack:25096 pid:12206 tgid:12206 ppid:5847 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5351 [inline] __schedule+0x1737/0x4d30 kernel/sched/core.c:6954 __schedule_loop kernel/sched/core.c:7036 [inline] schedule+0x165/0x360 kernel/sched/core.c:7051 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7108 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1187 __down_write_common kernel/locking/rwsem.c:1319 [inline] __down_write kernel/locking/rwsem.c:1328 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1593 mmap_write_lock include/linux/mmap_lock.h:356 [inline] userfaultfd_release_all+0x15a/0x5e0 mm/userfaultfd.c:2055 userfaultfd_release+0xe7/0x1b0 fs/userfaultfd.c:868 __fput+0x449/0xa70 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f650b78e9a9 RSP: 002b:00007ffec9cda648 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f650b9b7ba0 RCX: 00007f650b78e9a9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f650b9b7ba0 R08: 0000000000000000 R09: 0000000bc9cda93f R10: 00007f650b9b7ac0 R11: 0000000000000246 R12: 000000000005fe2a R13: 00007ffec9cda740 R14: ffffffffffffffff R15: 00007ffec9cda760 INFO: task syz.0.1830:12207 blocked for more than 143 seconds. Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1830 state:D stack:24472 pid:12207 tgid:12206 ppid:5847 task_flags:0x40044c flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5351 [inline] __schedule+0x1737/0x4d30 kernel/sched/core.c:6954 __schedule_loop kernel/sched/core.c:7036 [inline] schedule+0x165/0x360 kernel/sched/core.c:7051 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7108 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1088 __down_read_common kernel/locking/rwsem.c:1263 [inline] __down_read kernel/locking/rwsem.c:1276 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1541 mmap_read_lock include/linux/mmap_lock.h:412 [inline] exit_mm+0xcc/0x2c0 kernel/exit.c:557 do_exit+0x648/0x2300 kernel/exit.c:947 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f650b78e9a9 RSP: 002b:00007f650c59e0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f650b9b5fa8 RCX: 00007f650b78e9a9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f650b9b5fa8 RBP: 00007f650b9b5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f650b9b5fac R13: 0000000000000000 R14: 00007ffec9cda400 R15: 00007ffec9cda4e8 INFO: task syz.0.1830:12208 blocked for more than 144 seconds. Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1830 state:D stack:25512 pid:12208 tgid:12206 ppid:5847 task_flags:0x40044c flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5351 [inline] __schedule+0x1737/0x4d30 kernel/sched/core.c:6954 __schedule_loop kernel/sched/core.c:7036 [inline] schedule+0x165/0x360 kernel/sched/core.c:7051 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7108 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1088 __down_read_common kernel/locking/rwsem.c:1263 [inline] __down_read kernel/locking/rwsem.c:1276 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1541 mmap_read_lock include/linux/mmap_lock.h:412 [inline] exit_mm+0xcc/0x2c0 kernel/exit.c:557 do_exit+0x648/0x2300 kernel/exit.c:947 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f650b78e9a9 RSP: 002b:00007f650c57d038 EFLAGS: 00000246 ORIG_RAX: 000000000000000a RAX: fffffffffffffffc RBX: 00007f650b9b6080 RCX: 00007f650b78e9a9 RDX: 0000000000000003 RSI: 0000000000002000 RDI: 000020000093e000 RBP: 00007f650b810d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f650b9b6080 R15: 00007ffec9cda4e8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 3 locks held by kworker/u8:8/3497: #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000bc6fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000bc6fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 2 locks held by dhcpcd/5511: #0: ffffffff8f91cc48 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5ee/0x790 net/socket.c:1321 #1: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:577 2 locks held by getty/5614: #0: ffff88803453b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/u8:11/10610: #0: ffff88814c39f948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88814c39f948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90004a9fbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90004a9fbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4189 5 locks held by kworker/u8:12/10612: #0: ffff88801b6fe948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801b6fe948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90004b0fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90004b0fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8f92b870 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658 #3: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12683 #4: ffffffff8e543338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #4: ffffffff8e543338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:967 1 lock held by syz.0.1830/12206: #0: ffff88807f0557e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:356 [inline] #0: ffff88807f0557e0 (&mm->mmap_lock){++++}-{4:4}, at: userfaultfd_release_all+0x15a/0x5e0 mm/userfaultfd.c:2055 1 lock held by syz.0.1830/12207: #0: ffff88807f0557e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:412 [inline] #0: ffff88807f0557e0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 1 lock held by syz.0.1830/12208: #0: ffff88807f0557e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:412 [inline] #0: ffff88807f0557e0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 1 lock held by syz.0.1830/12209: 1 lock held by syz-executor/14443: #0: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979 1 lock held by syz-executor/14479: #0: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 3 locks held by syz.3.2537/14761: #0: ffffffff8f99d770 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8f99d588 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline] #1: ffffffff8f99d588 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline] #1: ffffffff8f99d588 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790 net/netlink/genetlink.c:1209 #2: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: team_nl_options_set_doit+0x99/0xde0 drivers/net/team/team_core.c:2530 2 locks held by syz.5.2541/14778: #0: ffffffff8f99d770 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8f99d588 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline] #1: ffffffff8f99d588 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline] #1: ffffffff8f99d588 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790 net/netlink/genetlink.c:1209 1 lock held by syz.5.2541/14779: #0: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: dev_ethtool+0x1d0/0x19b0 net/ethtool/ioctl.c:3531 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 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: 10605 Comm: kworker/u8:9 Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker RIP: 0010:lock_acquire+0x0/0x360 kernel/locking/lockdep.c:5831 Code: 05 75 9d 49 11 a9 00 ff ff 00 0f 95 c0 e9 18 a7 e4 09 cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 60 4d 89 ce 45 RSP: 0018:ffffc90004a77548 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffffffff89ebf04c RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e53d8a0 RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000000000 R12: ffffc90004a77813 R13: 0000000000000000 R14: ffff888072587300 R15: 000000000000ffff FS: 0000000000000000(0000) GS:ffff8881257ab000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000563038b47000 CR3: 000000003270e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000004144 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] rt_is_expired+0x38/0x2d0 net/ipv4/route.c:399 rt_cache_valid net/ipv4/route.c:1577 [inline] __mkroute_output net/ipv4/route.c:2640 [inline] ip_route_output_key_hash_rcu+0x13dc/0x23d0 net/ipv4/route.c:2866 ip_route_output_key_hash+0x1b9/0x2e0 net/ipv4/route.c:2696 __ip_route_output_key include/net/route.h:169 [inline] ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2923 send4+0x445/0xe20 drivers/net/wireguard/socket.c:61 wg_socket_send_skb_to_peer+0xd1/0x1d0 drivers/net/wireguard/socket.c:175 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x1db/0x320 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245