INFO: task syz.8.25:6271 blocked for more than 143 seconds. Not tainted 6.14.0-rc7-syzkaller-00186-gd07de43e3f05 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.25 state:D stack:27600 pid:6271 tgid:6270 ppid:6245 task_flags:0x400740 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 schedule_timeout+0x244/0x280 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116 wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264 coredump_wait fs/coredump.c:419 [inline] do_coredump+0x86f/0x4410 fs/coredump.c:576 get_signal+0x230b/0x26c0 kernel/signal.c:3021 arch_do_signal_or_restart+0x90/0x7e0 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:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb59378d169 RSP: 002b:00007fb59461d0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007fb5939a5fa8 RCX: 00007fb59378d169 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fb5939a5fac RBP: 00007fb5939a5fa0 R08: 00007fb59461e000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 00007fb5939a5fac R13: 0000000000000000 R14: 00007ffd3ae465e0 R15: 00007ffd3ae466c8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 3 locks held by kworker/u8:3/53: 2 locks held by getty/5598: #0: ffff88814d2fd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 3 locks held by kworker/u8:0/5904: #0: ffff88803117b948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3213 #1: ffffc9000422fd18 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3214 #2: ffffc90000a28cc0 (&(&nsim_dev->trap_data->trap_report_dw)->timer){..-.}-{0:0}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:598 3 locks held by kworker/u8:2/5945: #0: ffff88803117b948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3213 #1: ffff8880b8728a88 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2c1/0x8e0 kernel/sched/psi.c:987 #2: ffff8880b872a518 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x12f/0x1e0 kernel/time/timer.c:1046 1 lock held by syz.0.16/6064: 1 lock held by syz.1.17/6098: 1 lock held by syz.2.18/6116: 1 lock held by syz.3.19/6135: 2 locks held by syz.4.20/6159: 1 lock held by syz.5.21/6191: 1 lock held by syz.6.22/6216: 1 lock held by syz.7.23/6242: 1 lock held by syz.8.25/6272: 1 lock held by syz.9.31/6308: 1 lock held by syz.0.32/6333: 1 lock held by syz.1.33/6356: 1 lock held by syz.2.34/6378: 3 locks held by syz-executor/6381: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00186-gd07de43e3f05 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 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: 6381 Comm: syz-executor Not tainted 6.14.0-rc7-syzkaller-00186-gd07de43e3f05 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:416 Code: 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1c 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d c3 cc cc cc cc e8 01 83 dd fc eb a0 e8 8a 83 dd RSP: 0018:ffffc90002f96c88 EFLAGS: 00000002 RAX: 0000000000000033 RBX: 00000000000003f8 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff853ea9b5 RDI: ffffffff9ab72ea0 RBP: ffffffff9ab72e60 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000007 R12: 0000000000000000 R13: 0000000000000033 R14: ffffffff9ab72e60 R15: 0000000000000000 FS: 000055555968c500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9786b03440 CR3: 0000000068480000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_port_out include/linux/serial_core.h:796 [inline] serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3315 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3387 [inline] serial8250_console_write+0xfb1/0x1870 drivers/tty/serial/8250/8250_port.c:3465 console_emit_next_record kernel/printk/printk.c:3122 [inline] console_flush_all+0x800/0xc60 kernel/printk/printk.c:3210 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline] console_unlock+0xd9/0x210 kernel/printk/printk.c:3309 vprintk_emit+0x424/0x6f0 kernel/printk/printk.c:2432 _printk+0xc8/0x100 kernel/printk/printk.c:2457 batadv_check_known_mac_addr+0x230/0x440 net/batman-adv/hard-interface.c:528 batadv_hard_if_event+0x1025/0x1640 net/batman-adv/hard-interface.c:998 notifier_call_chain+0xb7/0x410 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:2206 call_netdevice_notifiers_extack net/core/dev.c:2244 [inline] call_netdevice_notifiers net/core/dev.c:2258 [inline] dev_set_mac_address+0x370/0x4a0 net/core/dev.c:9520 dev_set_mac_address_user+0x30/0x50 net/core/dev.c:9534 do_setlink.constprop.0+0x7bf/0x3f80 net/core/rtnetlink.c:3073 rtnl_changelink net/core/rtnetlink.c:3733 [inline] __rtnl_newlink net/core/rtnetlink.c:3885 [inline] rtnl_newlink+0x1306/0x1d60 net/core/rtnetlink.c:4022 rtnetlink_rcv_msg+0x95b/0xea0 net/core/rtnetlink.c:6912 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2533 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline] netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1338 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1882 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:733 [inline] __sys_sendto+0x488/0x4f0 net/socket.c:2187 __do_sys_sendto net/socket.c:2194 [inline] __se_sys_sendto net/socket.c:2190 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2190 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f898398effc Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b RSP: 002b:00007ffffc19f9d0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f89846d4620 RCX: 00007f898398effc RDX: 000000000000002c RSI: 00007f89846d4670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffffc19fa24 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f89846d4670 R15: 0000000000000000