INFO: task kworker/u8:11:2317 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:11 state:D stack:23696 pid:2317 tgid:2317 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x1681/0x54c0 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7563 rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1659 __rt_mutex_slowlock kernel/locking/rtmutex.c:1736 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1776 [inline] rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1816 __rt_mutex_lock kernel/locking/rtmutex.c:1831 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline] mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:553 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4206 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 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-executor:5822 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22256 pid:5822 tgid:5822 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x1681/0x54c0 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7563 rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1659 __rt_mutex_slowlock kernel/locking/rtmutex.c:1736 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1776 [inline] rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1816 __rt_mutex_lock kernel/locking/rtmutex.c:1831 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline] mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:553 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] devinet_ioctl+0x32b/0x1b30 net/ipv4/devinet.c:1120 inet_ioctl+0x42a/0x560 net/ipv4/af_inet.c:1011 sock_do_ioctl+0x101/0x320 net/socket.c:1313 sock_ioctl+0x5c9/0x7f0 net/socket.c:1434 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xff/0x170 fs/ioctl.c:583 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: 0033:0x7f958f79c4ab RSP: 002b:00007fffd03c66e0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fffd03c6800 RCX: 00007f958f79c4ab RDX: 00007fffd03c6760 RSI: 0000000000008914 RDI: 0000000000000005 RBP: 0000000000000025 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005 R13: 0000000000000047 R14: 00007f9590544620 R15: 00007fffd03c6760 INFO: task syz-executor:5826 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21696 pid:5826 tgid:5826 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x1681/0x54c0 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7563 rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1659 __rt_mutex_slowlock kernel/locking/rtmutex.c:1736 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1776 [inline] rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1816 __rt_mutex_lock kernel/locking/rtmutex.c:1831 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline] mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:553 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] inet6_rtm_newaddr+0x65f/0xe30 net/ipv6/addrconf.c:5039 rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6994 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x780/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg net/socket.c:802 [inline] __sys_sendto+0x67f/0x710 net/socket.c:2265 __do_sys_sendto net/socket.c:2272 [inline] __se_sys_sendto net/socket.c:2268 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2268 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: 0033:0x7efe998ad04e RSP: 002b:00007ffe7f778078 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555592ae2500 RCX: 00007efe998ad04e RDX: 0000000000000040 RSI: 00007efe9a694670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffe7f7780f4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 00007efe9a694670 R15: 0000000000000000 INFO: task kworker/0:5:5911 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:5 state:D stack:21232 pid:5911 tgid:5911 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_power_efficient crda_timeout_work Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x1681/0x54c0 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7563 rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1659 __rt_mutex_slowlock kernel/locking/rtmutex.c:1736 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1776 [inline] rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1816 __rt_mutex_lock kernel/locking/rtmutex.c:1831 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline] mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:553 crda_timeout_work+0x16/0x80 net/wireless/reg.c:529 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 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.1.2:5952 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.2 state:D stack:23712 pid:5952 tgid:5952 ppid:5820 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x1681/0x54c0 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7563 rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1659 __rt_mutex_slowlock kernel/locking/rtmutex.c:1736 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1776 [inline] rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1816 __rt_mutex_lock kernel/locking/rtmutex.c:1831 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline] mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:553 tun_detach drivers/net/tun.c:634 [inline] tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3438 __fput+0x461/0xa70 fs/file_table.c:510 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f903b19c819 RSP: 002b:00007ffedcaa5538 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f903b417da0 RCX: 00007f903b19c819 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f903b417da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007f903b417cb0 R11: 0000000000000246 R12: 00000000000162b2 R13: 00007f903b41609c R14: 0000000000016280 R15: 00007f903b416090 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:10/1719: #0: ffff88801a08c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801a08c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90007007c40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90007007c40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffff8880626108b8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6645 [inline] #2: ffff8880626108b8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x460 net/wireless/core.c:499 3 locks held by kworker/u8:11/2317: #0: ffff888032e49138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff888032e49138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90007717c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90007717c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4206 2 locks held by getty/5566: #0: ffff888037ad30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cb62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 4 locks held by kworker/0:4/5809: #0: ffff88801a04b938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801a04b938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc9000434fc40 (reg_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc9000434fc40 (reg_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: reg_todo+0x1c/0xa80 net/wireless/reg.c:3202 #3: ffff8880626108b8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6645 [inline] #3: ffff8880626108b8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_process_self_managed_hints+0x8d/0x170 net/wireless/reg.c:3192 1 lock held by syz-executor/5822: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x32b/0x1b30 net/ipv4/devinet.c:1120 1 lock held by syz-executor/5826: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x65f/0xe30 net/ipv6/addrconf.c:5039 3 locks held by kworker/1:3/5830: #0: ffff88801a04a538 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801a04a538 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc9000482fc40 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc9000482fc40 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0xab/0x1090 net/wireless/reg.c:2466 3 locks held by kworker/0:5/5911: #0: ffff88801a04a538 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801a04a538 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc9000506fc40 ((crda_timeout).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc9000506fc40 ((crda_timeout).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: crda_timeout_work+0x16/0x80 net/wireless/reg.c:529 1 lock held by syz.1.2/5952: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3438 1 lock held by syz-executor/6035: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by syz-executor/6295: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by syz-executor/6298: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by syz-executor/6444: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by syz-executor/6638: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by syz-executor/6643: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by syz.2.198/6693: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3438 2 locks held by syz.2.205/6719: #0: ffff888061612928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2404 #1: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6862 1 lock held by syz-executor/6828: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 2 locks held by syz.3.229/6852: #0: ffff8880636dc928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2404 #1: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6862 1 lock held by syz-executor/6857: #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36b1b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: 8b 61 02 e9 43 c7 03 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 63 db 1c 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffc900001d7e20 EFLAGS: 00000246 RAX: 00000000003e4a05 RBX: ffffffff819980da RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8d636465 RDI: ffffffff8ba73e60 RBP: ffffc900001d7f10 R08: ffff8880b8933e9b R09: 1ffff110171267d3 R10: dffffc0000000000 R11: ffffed10171267d4 R12: 0000000000000001 R13: 1ffff11003a5a000 R14: 0000000000000001 R15: 1ffff11003a5a000 FS: 0000000000000000(0000) GS:ffff8881261fe000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f199757fc0c CR3: 000000000ddb6000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/kernel/process.c:766 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x36a/0x5f0 kernel/sched/idle.c:352 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x147