INFO: task kworker/0:15:20391 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:15 state:D stack:24312 pid:20391 tgid:20391 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events netdev_rx_mode_work Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7379 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821 netdev_rx_mode_work+0x18/0x3c0 net/core/dev_addr_lists.c:1346 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478 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 INFO: task kworker/u8:3:13664 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:3 state:D stack:22328 pid:13664 tgid:13664 ppid:2 task_flags:0x4208160 flags:0x00080000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7379 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] addrconf_dad_work+0x116/0x15c0 net/ipv6/addrconf.c:4223 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478 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 INFO: task syz.2.21102:9000 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.21102 state:D stack:22592 pid:9000 tgid:8993 ppid:1722 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7379 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821 netdev_lock include/linux/netdevice.h:2837 [inline] netdev_lock_ops include/net/netdev_lock.h:42 [inline] __ethtool_get_link_ksettings+0x109/0x250 net/ethtool/ioctl.c:463 bond_update_speed_duplex drivers/net/bonding/bond_main.c:801 [inline] bond_slave_netdev_event drivers/net/bonding/bond_main.c:3982 [inline] bond_netdev_event+0x643/0xf80 drivers/net/bonding/bond_main.c:4089 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2288 [inline] call_netdevice_notifiers net/core/dev.c:2302 [inline] __dev_notify_flags+0x1aa/0x310 net/core/dev.c:9793 netif_change_flags+0xde/0x1b0 net/core/dev.c:9822 dev_change_flags+0x128/0x260 net/core/dev_api.c:68 vlan_device_event+0x1b4e/0x1f00 net/8021q/vlan.c:494 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2288 [inline] call_netdevice_notifiers net/core/dev.c:2302 [inline] __dev_notify_flags+0x1aa/0x310 net/core/dev.c:9793 netif_change_flags+0xde/0x1b0 net/core/dev.c:9822 do_setlink+0xdd6/0x4670 net/core/rtnetlink.c:3207 rtnl_group_changelink net/core/rtnetlink.c:3855 [inline] __rtnl_newlink net/core/rtnetlink.c:4023 [inline] rtnl_newlink+0x148e/0x1bd0 net/core/rtnetlink.c:4151 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7068 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] ____sys_sendmsg+0x9b9/0xa20 net/socket.c:2684 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738 __sys_sendmsg net/socket.c:2770 [inline] __do_sys_sendmsg net/socket.c:2775 [inline] __se_sys_sendmsg net/socket.c:2773 [inline] __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2773 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd1acd9ce59 RSP: 002b:00007fd1adc2a028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fd1ad016090 RCX: 00007fd1acd9ce59 RDX: 0000000004000000 RSI: 0000200000000200 RDI: 000000000000000b RBP: 00007fd1ace32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd1ad016128 R14: 00007fd1ad016090 R15: 00007fff9a5fcd58 INFO: task syz.4.21105:9005 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.21105 state:D stack:27280 pid:9005 tgid:9004 ppid:2177 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7379 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821 rtnl_lock net/core/rtnetlink.c:80 [inline] rtnetlink_rcv_msg+0x767/0xc00 net/core/rtnetlink.c:7074 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] ____sys_sendmsg+0x9b9/0xa20 net/socket.c:2684 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738 __sys_sendmmsg+0x273/0x4d0 net/socket.c:2827 __do_sys_sendmmsg net/socket.c:2854 [inline] __se_sys_sendmmsg net/socket.c:2851 [inline] __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2851 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5763b9ce59 RSP: 002b:00007f5761df6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f5763e15fa0 RCX: 00007f5763b9ce59 RDX: 040000000000009f RSI: 00002000000002c0 RDI: 0000000000000006 RBP: 00007f5763c32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5763e16038 R14: 00007f5763e15fa0 R15: 00007ffef19d3fc8 INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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+0xfd7/0x1030 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: 5215 Comm: kworker/u8:6 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: 0x0 (events_unbound) RIP: 0010:update_se+0x3cf/0x1020 kernel/sched/fair.c:1395 Code: 07 3f 9b 00 49 83 7d 00 00 4c 8b 6c 24 48 74 0b 4c 89 e7 4c 89 f6 e8 40 a3 28 00 0f 1f 44 00 00 4c 89 f0 48 83 c4 58 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 8f be 11 0a 85 c0 74 87 RSP: 0018:ffffc900051f78e0 EFLAGS: 00000092 RAX: 0000000000000000 RBX: ffff888030aa1f80 RCX: 1ffff110170e75f1 RDX: 1ffff110170e776c RSI: ffff888030aa1f80 RDI: ffff8880b873af80 RBP: 000001910d786eec R08: ffffc900051f7c48 R09: 1ffffffff20622de R10: dffffc0000000000 R11: fffffbfff20622df R12: ffff8880b873b050 R13: 1ffff110061543fc R14: 0000000000000000 R15: ffff888030aa1fe0 FS: 0000000000000000(0000) GS:ffff88812537c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000559f226ebee8 CR3: 000000000e746000 CR4: 00000000003526f0 Call Trace: update_curr+0x6c/0x440 kernel/sched/fair.c:2001 pick_task_fair+0x12d/0x1320 kernel/sched/fair.c:9931 __pick_next_task+0xdb/0x3c0 kernel/sched/core.c:6138 pick_next_task kernel/sched/core.c:-1 [inline] __schedule+0x901/0x56c0 kernel/sched/core.c:7143 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 worker_thread+0xc12/0xfb0 kernel/workqueue.c:3493 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