INFO: task syz.0.318:1502 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.318 state:D stack:0 pid:1502 tgid:1501 ppid:294 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6052 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7865 __schedule_loop kernel/sched/core.c:7942 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7957 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 rcu_barrier+0x45a/0x580 kernel/rcu/tree.c:4657 netdev_run_todo+0x118/0xce0 net/core/dev.c:10912 rtnl_unlock net/core/rtnetlink.c:152 [inline] rtnetlink_rcv_msg+0x903/0xa40 net/core/rtnetlink.c:6680 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+0x8bf/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] sock_write_iter+0x442/0x490 net/socket.c:1166 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x762/0xfd0 fs/read_write.c:684 ksys_write+0x145/0x260 fs/read_write.c:737 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x7f/0x90 fs/read_write.c:746 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2 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: 0033:0x7f2e30f9de59 RSP: 002b:00007f2e31e8a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f2e31225fa0 RCX: 00007f2e30f9de59 RDX: 0000000000000024 RSI: 0000200000000000 RDI: 0000000000000006 RBP: 00007f2e31033e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2e31226038 R14: 00007f2e31225fa0 R15: 00007ffcdc110d28 INFO: task Á:1503 blocked for more than 124 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:Á state:D stack:0 pid:1503 tgid:1501 ppid:294 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:6052 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7865 __schedule_loop kernel/sched/core.c:7942 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7957 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8014 __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 rcu_barrier+0x4d/0x580 kernel/rcu/tree.c:4589 netdev_run_todo+0x118/0xce0 net/core/dev.c:10912 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152 tun_detach drivers/net/tun.c:704 [inline] tun_chr_close+0xc5/0x150 drivers/net/tun.c:3520 __fput+0x208/0xa30 fs/file_table.c:447 ____fput+0x20/0x30 fs/file_table.c:475 task_work_run+0x1e8/0x260 kernel/task_work.c:246 get_signal+0x12b3/0x1490 kernel/signal.c:2706 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: 0033:0x7f2e30f9de59 RSP: 002b:00007f2e31e69028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007f2e31226090 RCX: 00007f2e30f9de59 RDX: 0000000000000304 RSI: 00000000400454cd RDI: 0000000000000003 RBP: 00007f2e31033e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2e31226128 R14: 00007f2e31226090 R15: 00007ffcdc110d28 INFO: task syz.3.326:1532 blocked for more than 128 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.326 state:D stack:0 pid:1532 tgid:1532 ppid:295 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:6052 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7865 __schedule_loop kernel/sched/core.c:7942 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7957 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8014 __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 rcu_barrier+0x4d/0x580 kernel/rcu/tree.c:4589 kvm_mmu_uninit_tdp_mmu+0x1ea/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51 kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6569 kvm_arch_destroy_vm+0x395/0x410 arch/x86/kvm/x86.c:13008 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline] kvm_put_kvm+0xadf/0x12d0 virt/kvm/kvm_main.c:1392 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415 __fput+0x208/0xa30 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 __do_sys_exit_group kernel/exit.c:1109 [inline] __se_sys_exit_group kernel/exit.c:1107 [inline] __x64_sys_exit_group+0x43/0x50 kernel/exit.c:1107 x64_sys_call+0x2ed2/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:232 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: 0033:0x7feae6d9de59 RSP: 002b:00007ffd50c88fe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007feae6e33509 RCX: 00007feae6d9de59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000009 R08: 0000000000000000 R09: 0000000000000003 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000003 R14: 0000000000000000 R15: 00007feae7025fa0 INFO: task syz.2.327:1534 blocked for more than 130 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.327 state:D stack:0 pid:1534 tgid:1534 ppid:296 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6052 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7865 __schedule_loop kernel/sched/core.c:7942 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7957 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8014 __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 rcu_barrier+0x4d/0x580 kernel/rcu/tree.c:4589 kvm_mmu_uninit_tdp_mmu+0x1ea/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51 kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6569 kvm_arch_destroy_vm+0x395/0x410 arch/x86/kvm/x86.c:13008 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline] kvm_put_kvm+0xadf/0x12d0 virt/kvm/kvm_main.c:1392 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415 __fput+0x208/0xa30 fs/file_table.c:447 ____fput+0x20/0x30 fs/file_table.c:475 task_work_run+0x1e8/0x260 kernel/task_work.c:246 resume_user_mode_work+0x35/0x50 include/linux/resume_user_mode.h:50 exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x63/0xb0 kernel/entry/common.c:218 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7ffa5f99de59 RSP: 002b:00007ffebf17e6d8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007ffa5fc27da0 RCX: 00007ffa5f99de59 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007ffa5fc27da0 R08: 00007ffa5fc26038 R09: 0000000000000000 R10: 000000000003fcc4 R11: 0000000000000246 R12: 00000000000143a4 R13: 00007ffa5fc2609c R14: 00000000000143a4 R15: 00007ffa5fc26090 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 35c7ec5060a775d4d4f6b490df0454f0e9b62d01 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 33 Comm: rcuop/1 Not tainted syzkaller #0 35c7ec5060a775d4d4f6b490df0454f0e9b62d01 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0xc/0x90 kernel/kcov.c:314 Code: 89 44 11 20 5d c3 cc cc cc cc cc 0f 1f 00 b8 4f be 1b 8d 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 48 8b 45 08 <65> 48 8b 15 5c 77 7d 7e 65 8b 0d 5d 77 7d 7e 81 e1 00 01 ff 00 74 RSP: 0018:ffffc900000072d0 EFLAGS: 00000246 RAX: ffffffff84fbc88d RBX: 1ffff110217e5e0c RCX: ffff88810367df00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900000072d0 R08: ffffc90000007540 R09: ffffc90000007550 R10: ffffc900000076b0 R11: fffff52000000eda R12: 0000000000000100 R13: dffffc0000000000 R14: ffff88810bf2f000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcb9c757e20 CR3: 000000010cf78000 CR4: 00000000003526b0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: fib6_check_expired include/net/ip6_fib.h:280 [inline] __find_rr_leaf+0x18d/0x840 net/ipv6/route.c:843 find_rr_leaf net/ipv6/route.c:890 [inline] rt6_select net/ipv6/route.c:934 [inline] fib6_table_lookup+0x2d0/0x980 net/ipv6/route.c:2242 ip6_pol_route+0x17a/0x1370 net/ipv6/route.c:2278 ip6_pol_route_input+0x5a/0x80 net/ipv6/route.c:2335 pol_lookup_func include/net/ip6_fib.h:647 [inline] fib6_rule_lookup+0x4f1/0x6d0 net/ipv6/fib6_rules.c:117 ip6_route_input_lookup net/ipv6/route.c:2347 [inline] ip6_route_input+0x60d/0x8d0 net/ipv6/route.c:2643 ip6_rcv_finish_core net/ipv6/ip6_input.c:66 [inline] ip6_rcv_finish+0x15a/0x3c0 net/ipv6/ip6_input.c:77 NF_HOOK include/linux/netfilter.h:317 [inline] ipv6_rcv+0xf1/0x240 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core net/core/dev.c:5801 [inline] __netif_receive_skb net/core/dev.c:5914 [inline] process_backlog+0x472/0xaf0 net/core/dev.c:6250 __napi_poll+0xcd/0x600 net/core/dev.c:6901 napi_poll net/core/dev.c:6970 [inline] net_rx_action+0x5dc/0xd70 net/core/dev.c:7092 handle_softirqs+0x1aa/0x620 kernel/softirq.c:621 __do_softirq+0xf/0x16 kernel/softirq.c:659 do_softirq+0xb8/0x110 kernel/softirq.c:503 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_do_batch+0x590/0xcb0 kernel/rcu/tree.c:2594 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline] rcu_nocb_cb_kthread+0x533/0xb60 kernel/rcu/tree_nocb.h:957 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