INFO: task syz.7.3501:14428 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.3501 state:D stack:26728 pid:14428 ppid:13128 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 perf_pending_task_sync kernel/events/core.c:5242 [inline] _free_event+0x174/0xf30 kernel/events/core.c:5248 put_event kernel/events/core.c:5376 [inline] perf_event_release_kernel+0x836/0x8c0 kernel/events/core.c:5501 perf_release+0x3b/0x40 kernel/events/core.c:5511 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1ce/0x250 kernel/task_work.c:239 get_signal+0x1235/0x1400 kernel/signal.c:2678 arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xf6/0x180 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:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fb46b58ec29 RSP: 002b:00007fb46c3d0038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffea RBX: 00007fb46b7d6090 RCX: 00007fb46b58ec29 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000180 RBP: 00007fb46b611e41 R08: 0000000000000002 R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb46b7d6128 R14: 00007fb46b7d6090 R15: 00007ffe7ed763c8 Showing all locks held in the system: 2 locks held by kworker/u4:0/11: #0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc90000107d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90000107d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 2 locks held by kworker/1:0/23: #0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc900001d7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900001d7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 1 lock held by khungtaskd/29: #0: ffffffff8cd2fe20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2fe20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2fe20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5555: #0: ffff88802d03f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 3 locks held by kworker/u4:7/15102: #0: ffff88814be88138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff88814be88138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc900050a7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900050a7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffffffff8dfbc3c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x14e0 net/ipv6/addrconf.c:4158 2 locks held by syz.9.4585/17003: #0: ffffffff8dfbc3c8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8dfbc3c8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3511 #1: ffffffff8cd357f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #1: ffffffff8cd357f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x830 kernel/rcu/tree_exp.h:1004 2 locks held by syz.8.4586/17008: #0: ffff888029328690 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0xf4/0x810 net/netlink/af_netlink.c:2336 #1: ffffffff8dfbc3c8 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0x71f/0xde0 net/netlink/af_netlink.c:2263 4 locks held by syz.8.4586/17009: ============================================= 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 08/18/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 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+0xf41/0xf80 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: 17009 Comm: syz.8.4586 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline] RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:196 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 f3 0f 1e fa 89 f6 31 d2 e9 d7 e5 18 03 0f 1f 80 00 00 00 RSP: 0018:ffffc900001f0e58 EFLAGS: 00000046 RAX: 000000000000014a RBX: ffff8880b8f28280 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000000014a RDI: 0000000000000838 RBP: 0000000000000000 R08: ffffffff8e4a91af R09: 1ffffffff1c95235 R10: dffffc0000000000 R11: fffffbfff1c95236 R12: dffffc0000000000 R13: 00000000100064a9 R14: 000000000000014a R15: 0000000000000020 FS: 00007f5c313dd6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2e61cff8 CR3: 000000005d777000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: apic_write arch/x86/include/asm/apic.h:404 [inline] lapic_next_event+0x11/0x20 arch/x86/kernel/apic/apic.c:448 clockevents_program_event+0x1c0/0x310 kernel/time/clockevents.c:334 hrtimer_interrupt+0x5a1/0x9c0 kernel/time/hrtimer.c:1889 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__sanitizer_cov_trace_pc+0x57/0x60 kernel/kcov.c:232 Code: 00 74 2c 8b 91 f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc 15 00 00 48 39 cf 73 08 48 89 3a <48> 89 44 f2 08 c3 0f 1f 00 f3 0f 1e fa 48 8b 04 24 65 48 8b 15 b0 RSP: 0018:ffffc9000b6e75b0 EFLAGS: 00000287 RAX: ffffffff89b4e5e0 RBX: dffffc0000000000 RCX: 0000000000080000 RDX: ffffc90012008000 RSI: 000000000001e61d RDI: 000000000001e61e RBP: 0000000000000000 R08: ffff888024525a00 R09: 0000000000000002 R10: 000000000000000a R11: 0000000000000002 R12: ffffffff8e1eb610 R13: ffff888060cd9bbd R14: ffff88801b2c6088 R15: ffff888060cd9b80 sctp_bind_addr_state+0xe0/0x1a0 net/sctp/bind_addr.c:413 sctp_copy_local_addr_list+0x2d5/0x4e0 net/sctp/protocol.c:162 sctp_bind_addr_copy+0xb3/0x3c0 net/sctp/bind_addr.c:56 sctp_connect_new_asoc+0x2da/0x690 net/sctp/socket.c:1095 sctp_sendmsg_new_asoc net/sctp/socket.c:1693 [inline] sctp_sendmsg+0x155c/0x27e0 net/sctp/socket.c:2004 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5bf/0x950 net/socket.c:2595 ___sys_sendmsg+0x220/0x290 net/socket.c:2649 __sys_sendmsg net/socket.c:2678 [inline] __do_sys_sendmsg net/socket.c:2687 [inline] __se_sys_sendmsg+0x1a5/0x270 net/socket.c:2685 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5c3058ec29 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5c313dd038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f5c307d6180 RCX: 00007f5c3058ec29 RDX: 00000000040080c0 RSI: 00002000000003c0 RDI: 0000000000000005 RBP: 00007f5c30611e41 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5c307d6218 R14: 00007f5c307d6180 R15: 00007fffc48dd488