INFO: task syz.3.2120:12995 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.2120 state:D stack:24936 pid:12995 ppid:5773 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 perf_pending_task_sync kernel/events/core.c:5244 [inline] _free_event+0x174/0xf30 kernel/events/core.c:5250 put_event kernel/events/core.c:5378 [inline] perf_event_release_kernel+0x842/0x8d0 kernel/events/core.c:5503 perf_release+0x3b/0x40 kernel/events/core.c:5513 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1d4/0x260 kernel/task_work.c:245 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x95a/0x2460 kernel/exit.c:884 do_group_exit+0x21b/0x2d0 kernel/exit.c:1026 get_signal+0x12fc/0x13f0 kernel/signal.c:2902 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd5f799ce59 RSP: 002b:00007fd5f884a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000035 RAX: ffffffffffffff9f RBX: 00007fd5f7c15fa0 RCX: 00007fd5f799ce59 RDX: 0000000000000774 RSI: 0000000000000800 RDI: 0000000000000024 RBP: 00007fd5f7a32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000200000000380 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd5f7c16038 R14: 00007fd5f7c15fa0 R15: 00007ffd70b11608 Showing all locks held in the system: 2 locks held by rcu_tasks_trace/15: #0: ffffffff8d132e90 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0xadb/0xdb0 kernel/rcu/tasks.h:607 #1: ffffffff8d137b38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #1: ffffffff8d137b38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004 1 lock held by khungtaskd/29: #0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5534: #0: ffff8880314490a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217 2 locks held by kworker/0:9/9393: #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 #1: ffffc9000561fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc9000561fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 2 locks held by syz.2.2887/15877: 1 lock held by syz.1.2906/15951: #0: ffff888026e10670 (&kcm->tx_mutex){+.+.}-{3:3}, at: kcm_sendmsg+0x1b5/0x28b0 net/kcm/kcmsock.c:757 1 lock held by syz.2.2912/15974: 1 lock held by syz.2.2912/15977: 1 lock held by syz.0.2913/15971: #0: ffffffff8e3c6988 (rtnl_mutex){+.+.}-{3:3}, at: bpf_xdp_link_release+0x7f/0x4d0 net/core/dev.c:9497 2 locks held by syz.0.2913/15972: #0: ffffffff8e3c6988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff8e3c6988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x811/0xfa0 net/core/rtnetlink.c:6473 #1: ffffffff8d137b38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline] #1: ffffffff8d137b38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x306/0x880 kernel/rcu/tree_exp.h:1004 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf3d/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 15977 Comm: syz.2.2912 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:pvclock_read_begin arch/x86/include/asm/pvclock.h:24 [inline] RIP: 0010:__pvclock_clocksource_read arch/x86/kernel/pvclock.c:76 [inline] RIP: 0010:pvclock_clocksource_read_nowd+0x0/0xf0 arch/x86/kernel/pvclock.c:120 Code: 1f 02 c3 cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d 43 e4 3f 00 fb f4 c3 <66> 0f 1f 00 55 41 57 41 56 41 54 53 50 8b 2f eb 2e 41 89 de 80 fb RSP: 0000:ffffc900001f0518 EFLAGS: 00000002 RAX: ffffffff8130c89b RBX: ffff8880b8f28858 RCX: ffff888022bb0000 RDX: 0000000000010100 RSI: ffffffff8b1c9c00 RDI: ffffffff900c2040 RBP: ffffc900001f0618 R08: ffffffff8e8b666f R09: 1ffffffff1d16ccd R10: dffffc0000000000 R11: fffffbfff1d16cce R12: dffffc0000000000 R13: dffffc0000000000 R14: ffffc900001f05a0 R15: 1ffff9200003e0b0 FS: 00007f274ee6c6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f60684ce664 CR3: 0000000063ada000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000008d24 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: kvm_sched_clock_read+0x11/0x20 arch/x86/kernel/kvmclock.c:91 sched_clock+0x17/0x60 arch/x86/kernel/tsc.c:283 sched_clock_cpu+0x75/0x430 kernel/sched/clock.c:394 irqtime_account_irq+0x6e/0x1c0 kernel/sched/cputime.c:64 account_hardirq_exit include/linux/vtime.h:159 [inline] __irq_exit_rcu+0x99/0x190 kernel/softirq.c:658 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__dev_queue_xmit+0x0/0x3660 net/core/dev.c:4359 Code: e0 63 f9 e9 31 fe ff ff 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c 23 ff ff ff 4c 89 e7 e8 29 e0 63 f9 e9 16 ff ff ff 0f 1f 40 00 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 RSP: 0000:ffffc900001f07b8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff11003cf4036 RCX: ffff888022bb0000 RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff88801e7a0140 RBP: ffffc900001f08f0 R08: 0200000033330000 R09: dd863eaaaaaaaaaa R10: 0200000033330000 R11: dd863eaaaaaaaaaa R12: ffff88801e7a0218 R13: 000000000000000e R14: ffff88801e7a0140 R15: dffffc0000000000 dev_queue_xmit include/linux/netdevice.h:3113 [inline] neigh_hh_output include/net/neighbour.h:527 [inline] neigh_output include/net/neighbour.h:541 [inline] ip6_finish_output2+0xe06/0x1630 net/ipv6/ip6_output.c:141 dst_output include/net/dst.h:467 [inline] NF_HOOK include/linux/netfilter.h:304 [inline] ndisc_send_skb+0xc26/0x14f0 net/ipv6/ndisc.c:513 addrconf_rs_timer+0x2d5/0x630 net/ipv6/addrconf.c:4024 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x542/0x800 kernel/time/timer.c:2023 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:preempt_schedule_irq+0xba/0x150 kernel/sched/core.c:7010 Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 6f bf 01 00 00 00 e8 a1 ea cb f6 e8 4c fd fc f6 fb bf 01 00 00 00 f1 b4 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f RSP: 0000:ffffc900036d7da0 EFLAGS: 00000286 RAX: e6d1edfe044e0100 RBX: 0000000000000000 RCX: e6d1edfe044e0100 RDX: dffffc0000000000 RSI: ffffffff8acacbe0 RDI: 0000000000000001 RBP: ffffc900036d7e50 R08: ffffffff8e8b666f R09: 1ffffffff1d16ccd R10: dffffc0000000000 R11: fffffbfff1d16cce R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920006dafb4 irqentry_exit+0x67/0x70 kernel/entry/common.c:438 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:exit_to_user_mode_loop+0x40/0x110 kernel/entry/common.c:164 Code: fb eb 1d e8 72 92 14 09 65 48 8b 05 3a d8 8f 7e 4c 8b 30 41 f7 c6 0e 30 02 00 0f 84 c4 00 00 00 e8 a5 c0 19 00 fb 41 f6 c6 08 <74> 05 e8 e9 bd 1c 09 41 f7 c6 00 10 00 00 74 08 48 89 df e8 d8 b1 RSP: 0000:ffffc900036d7f10 EFLAGS: 00000246 RAX: e6d1edfe044e0100 RBX: ffffc900036d7f58 RCX: e6d1edfe044e0100 RDX: dffffc0000000000 RSI: ffffffff8acacbe0 RDI: ffffffff8b1c9c20 RBP: 0000000000000000 R08: ffffffff8e8b666f R09: 1ffffffff1d16ccd R10: dffffc0000000000 R11: fffffbfff1d16cce R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000004 R15: ffff888022bb0000 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 irqentry_exit_to_user_mode+0x9/0x30 kernel/entry/common.c:315 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:723 RIP: 0033:0x7f274df9ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f274ee6c028 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f274e216180 RCX: 00007f274df9ce59 RDX: 0000000000000009 RSI: 0000000040042408 RDI: 0000000000000008 RBP: 00007f274e032d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f274e216218 R14: 00007f274e216180 R15: 00007ffd81ef09c8