INFO: task khugepaged:41 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:khugepaged state:D stack:0 pid:41 tgid:41 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:6054 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7867 __schedule_loop kernel/sched/core.c:7944 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7959 schedule_timeout+0xc7/0x3b0 kernel/time/timer.c:2596 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common+0x368/0x650 kernel/sched/completion.c:127 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148 __flush_work+0x6a8/0xaa0 kernel/workqueue.c:4290 flush_work+0x1b/0x40 kernel/workqueue.c:4312 __lru_add_drain_all+0x51c/0x580 mm/swap.c:923 lru_add_drain_all+0x14/0x30 mm/swap.c:931 khugepaged_do_scan mm/khugepaged.c:2531 [inline] khugepaged+0x18a/0x1930 mm/khugepaged.c:2600 kthread+0x2c7/0x360 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz-executor:296 blocked for more than 124 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:296 tgid:296 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:6054 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7867 __schedule_loop kernel/sched/core.c:7944 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7959 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8016 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79 tun_detach drivers/net/tun.c:698 [inline] tun_chr_close+0x41/0x150 drivers/net/tun.c:3520 __fput+0x20b/0xa30 fs/file_table.c:447 ____fput+0x20/0x30 fs/file_table.c:475 task_work_run+0x1e8/0x260 kernel/task_work.c:246 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xa46/0x2850 kernel/exit.c:955 do_group_exit+0x21f/0x2f0 kernel/exit.c:1098 get_signal+0x134c/0x1490 kernel/signal.c:2933 arch_do_signal_or_restart+0xbc/0x700 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f7e94359017 RSP: 002b:00007ffd84c27a90 EFLAGS: 00000202 ORIG_RAX: 000000000000003d RAX: fffffffffffffe00 RBX: 000055558bcf4500 RCX: 00007f7e94359017 RDX: 0000000040000000 RSI: 00007ffd84c27b1c RDI: ffffffffffffffff RBP: 00007ffd84c27b1c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000047 R13: 000055558bd078e0 R14: 0000000000000005 R15: 00007ffd84c27b70 INFO: task syz.1.142:913 blocked for more than 125 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.142 state:D stack:0 pid:913 tgid:913 ppid:293 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:6054 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7867 __schedule_loop kernel/sched/core.c:7944 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7959 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8016 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79 tun_detach drivers/net/tun.c:698 [inline] tun_chr_close+0x41/0x150 drivers/net/tun.c:3520 __fput+0x20b/0xa30 fs/file_table.c:447 ____fput+0x20/0x30 fs/file_table.c:475 task_work_run+0x1e8/0x260 kernel/task_work.c:246 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xa46/0x2850 kernel/exit.c:955 do_group_exit+0x21f/0x2f0 kernel/exit.c:1098 get_signal+0x134c/0x1490 kernel/signal.c:2933 arch_do_signal_or_restart+0xbc/0x700 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7ff96995e6ce RSP: 002b:00007ff96a808f58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007ff96a8096c0 RCX: 00007ff96995e6ce RDX: 00007ff96a808fb0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ff969a33eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff969c26038 R14: 00007ff969c25fa0 R15: 00007ffdbbe03728 INFO: task syz-executor:1317 blocked for more than 126 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:1317 tgid:1317 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6054 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7867 __schedule_loop kernel/sched/core.c:7944 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7959 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8016 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676 netlink_rcv_skb+0x24a/0x4e0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8bc/0xa70 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x68a/0x700 net/socket.c:2216 __do_sys_sendto net/socket.c:2228 [inline] __se_sys_sendto net/socket.c:2224 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2224 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f8bded59017 RSP: 002b:00007ffde98232d0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555584c24500 RCX: 00007f8bded59017 RDX: 0000000000000028 RSI: 00007f8bdfb54670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffde9823334 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f8bdfb54670 R15: 0000000000000000 INFO: task syz-executor:1319 blocked for more than 126 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:1319 tgid:1319 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6054 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7867 __schedule_loop kernel/sched/core.c:7944 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7959 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8016 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676 netlink_rcv_skb+0x24a/0x4e0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8bc/0xa70 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x68a/0x700 net/socket.c:2216 __do_sys_sendto net/socket.c:2228 [inline] __se_sys_sendto net/socket.c:2224 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2224 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fac6c559017 RSP: 002b:00007ffe65bbf330 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555589af0500 RCX: 00007fac6c559017 RDX: 0000000000000028 RSI: 00007fac6d354670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffe65bbf394 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fac6d354670 R15: 0000000000000000 INFO: task syz-executor:1321 blocked for more than 127 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:R running task stack:0 pid:1321 tgid:1321 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6054 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7867 __schedule_loop kernel/sched/core.c:7944 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7959 exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] synchronize_rcu_expedited+0x50e/0x960 kernel/rcu/tree_exp.h:978 namespace_unlock+0x248/0x450 fs/namespace.c:1720 drop_collected_mounts fs/namespace.c:2248 [inline] put_mnt_ns+0xad/0xf0 fs/namespace.c:5655 free_nsproxy+0x52/0x290 kernel/nsproxy.c:193 put_nsproxy include/linux/nsproxy.h:118 [inline] switch_task_namespaces kernel/nsproxy.c:251 [inline] exit_task_namespaces+0x99/0xe0 kernel/nsproxy.c:256 do_exit+0xa41/0x2850 kernel/exit.c:954 do_group_exit+0x21f/0x2f0 kernel/exit.c:1098 get_signal+0x134c/0x1490 kernel/signal.c:2933 arch_do_signal_or_restart+0xbc/0x700 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f19fab59017 RSP: 002b:00007ffee978fda0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: 0000000000000028 RBX: 000055556048e500 RCX: 00007f19fab59017 RDX: 0000000000000028 RSI: 00007f19fb954670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffee978fe04 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f19fb954670 R15: 0000000000000000 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 5adf726ab28801c07fd45706e49e1b3a66128c4b Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline] watchdog+0xe45/0xf90 kernel/hung_task.c:423 kthread+0x2c7/0x360 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 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 5adf726ab28801c07fd45706e49e1b3a66128c4b Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:116 Code: cc cc cc cc cc cc cc b8 97 4a eb 13 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 23 d9 43 00 55 48 89 e5 fb f4 <5d> c3 cc cc cc cc cc cc cc cc cc cc cc b8 00 00 00 00 90 90 90 90 RSP: 0018:ffffc900001a7e00 EFLAGS: 000002c2 RAX: ffff8881f6f00000 RBX: ffff888103669300 RCX: ffffffff85a384fd RDX: 0000000000000001 RSI: 0000000000000004 RDI: 000000000015786c RBP: ffffc900001a7e00 R08: ffff8881f6f395eb R09: 1ffff1103ede72bd R10: dffffc0000000000 R11: ffffed103ede72be R12: 0000000000000000 R13: 1ffff110206cd260 R14: dffffc0000000000 R15: ffffffff87ecb2a8 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562c64f91af8 CR3: 000000010cb3a000 CR4: 00000000003526b0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:-1 [inline] default_idle+0x17/0x30 arch/x86/kernel/process.c:754 arch_cpu_idle+0xd/0x20 arch/x86/kernel/process.c:791 default_idle_call+0x3e/0x80 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:193 [inline] do_idle+0x2fc/0x570 kernel/sched/idle.c:346 cpu_startup_entry+0x47/0x60 kernel/sched/idle.c:445 start_secondary+0x12e/0x140 arch/x86/kernel/smpboot.c:314 common_startup_64+0x13b/0x157