INFO: task syz.4.5548:21572 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.5548 state:D stack:27672 pid:21572 tgid:21571 ppid:16093 task_flags:0x400140 flags:0x00080002 Call Trac[ 1177.410081][ T40] Call Trace: context_switch kernel/sched/core.c:5402 [inline] __schedule+0x16f9/0x5500 kernel/sched/core.c:7204 __schedule_loop kernel/sched/core.c:7283 [inline] schedule+0x164/0x360 kernel/sched/core.c:7298 cgroup_lock_and_drain_offline+0x516/0x650 kernel/cgroup/cgroup.c:3248 cgroup_kn_lock_live+0x120/0x230 kernel/cgroup/cgroup.c:1699 cgroup_subtree_control_write+0x4b3/0x10a0 kernel/cgroup/cgroup.c:3550 cgroup_file_write+0x331/0x8f0 kernel/cgroup/cgroup.c:4289 kernfs_fop_write_iter+0x3b0/0x540 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x629/0xba0 fs/read_write.c:688 ksys_write+0x156/0x270 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fee1c4ece59 RSP: 002b:00007fee1a73e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fee1c765fa0 RCX: 00007fee1c4ece59 RDX: 0000000000000005 RSI: 0000200000000300 RDI: 0000000000000006 RBP: 00007fee1c582d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fee1c766038 R14: 00007fee1c765fa0 R15: 00007ffe97293288 Showing all locks held in the system: 4 locks held by pr/legacy/17: #0: ffffffff8e1bccc0 (console_lock){+.+.}-{0:0}, at: legacy_kthread_func+0x1a3/0x250 kernel/printk/printk.c:3711 #1: ffffffff8e0a45b8 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:305 [inline] #1: ffffffff8e0a45b8 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:428 [inline] #1: ffffffff8e0a45b8 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:291 [inline] #1: ffffffff8e0a45b8 (console_srcu){....}-{0:0}, at: console_flush_one_record+0xfa/0xb90 kernel/printk/printk.c:3246 #2: ffffffff99e10018 (&port_lock_key){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #2: ffffffff99e10018 (&port_lock_key){+.+.}-{3:3}, at: uart_port_lock_irqsave include/linux/serial_core.h:719 [inline] #2: ffffffff99e10018 (&port_lock_key){+.+.}-{3:3}, at: serial8250_console_write+0x178/0x1b50 drivers/tty/serial/8250/8250_port.c:3338 #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 1 lock held by khungtaskd/40: #0: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777 2 locks held by getty/5362: #0: ffff8880363240a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 5 locks held by kworker/u8:35/8554: #0: ffff88813fe54138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3293 #1: ffffc90005c5fc40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3294 #2: ffff88802a14e310 (&devlink->lock_key#13){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xbd0 drivers/net/netdevsim/dev.c:909 #3: ffff888058aff920 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #3: ffff888058aff920 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: nsim_dev_trap_report drivers/net/netdevsim/dev.c:862 [inline] #3: ffff888058aff920 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x1ad/0xbd0 drivers/net/netdevsim/dev.c:922 #4: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #4: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #4: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #4: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 5 locks held by kworker/u8:56/12106: #0: ffff888032344138 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3293 #1: ffffc90005f7fc40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3294 #2: ffffffff8e0613c0 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 #4: ffff8880595aa0d8 (&hash->list_locks[i]){+...}-{3:3}, at: spin_lock_bh include/linux/spinlock_rt.h:90 [inline] #4: ffff8880595aa0d8 (&hash->list_locks[i]){+...}-{3:3}, at: __batadv_dat_purge+0x131/0x400 net/batman-adv/distributed-arp-table.c:173 7 locks held by syz-executor/19597: #0: ffffffff99ad1738 (&fsnotify_mark_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline] #0: ffffffff99ad1738 (&fsnotify_mark_srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline] #0: ffffffff99ad1738 (&fsnotify_mark_srcu){.+.+}-{0:0}, at: fsnotify+0x846/0x1d90 fs/notify/fsnotify.c:568 #1: ffff8880119120f8 (&group->notification_waitq){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #1: ffff8880119120f8 (&group->notification_waitq){+.+.}-{3:3}, at: __wake_up_common_lock+0x2f/0x1e0 kernel/sched/wait.c:124 #2: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #2: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #2: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #2: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 #3: ffff888011a19a08 (&ep->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #3: ffff888011a19a08 (&ep->lock){+.+.}-{3:3}, at: ep_poll_callback+0x79/0x800 fs/eventpoll.c:1462 #4: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #4: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #4: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #4: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 #5: ffff888011a198d8 (&ep->wq){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #5: ffff888011a198d8 (&ep->wq){+.+.}-{3:3}, at: __wake_up_common_lock+0x2f/0x1e0 kernel/sched/wait.c:124 #6: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #6: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #6: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #6: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 3 locks held by syz.4.5548/21572: #0: ffff88803a969f28 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1260 #1: ffff88803be1c480 (sb_writers#9){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #1: ffff88803be1c480 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684 #2: ffff888028ff8878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343 9 locks held by syz-executor/21764: #0: ffffffff8e29d2b0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1541 [inline] #0: ffffffff8e29d2b0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x10f/0x480 kernel/fork.c:1594 #1: ffff888067e3e2b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline] #1: ffff888067e3e2b0 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x184/0x1d70 mm/mmap.c:1739 #2: ffff88801169f030 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:544 [inline] #2: ffff88801169f030 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x272/0x1d70 mm/mmap.c:1746 #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:290 #4: ffff8880298c9dd8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #4: ffff8880298c9dd8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404 #5: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #5: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #5: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #5: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 #6: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #6: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #6: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:290 #7: ffff88803eaf8718 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pte_range mm/memory.c:1272 [inline] #7: ffff88803eaf8718 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pmd_range+0x5ae/0x5550 mm/memory.c:1408 #8: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #8: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #8: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #8: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock_nested+0x1de/0x3f0 kernel/locking/spinlock_rt.c:65 8 locks held by syz-executor/24651: #0: ffff888034cec480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff888034cec480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684 #1: ffff88805d8c7c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343 #2: ffff8880258c03c8 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8880258c03c8 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344 #3: ffffffff8ee21ab8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x13c/0x710 drivers/net/netdevsim/bus.c:184 #4: ffff8880377f9160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #4: ffff8880377f9160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1073 #5: ffff888067ce4310 (&devlink->lock_key#15){+.+.}-{4:4}, at: nsim_drv_probe+0xcf/0xc20 drivers/net/netdevsim/dev.c:1658 #6: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1057 [inline] #6: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_create+0x894/0x1170 drivers/net/netdevsim/netdev.c:1151 #7: ffffffff8eb6a318 (dpm_list_mtx){+.+.}-{4:4}, at: device_pm_add+0x7d/0x350 drivers/base/power/main.c:152 1 lock held by syz.2.6968/25067: #0: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x3bf/0x1e30 drivers/net/tun.c:3147 3 locks held by syz.2.6968/25070: #0: ffffffff8f61d740 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8f61d558 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline] #1: ffffffff8f61d558 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline] #1: ffffffff8f61d558 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208 #2: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: __tipc_nl_compat_doit net/tipc/netlink_compat.c:355 [inline] #2: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: tipc_nl_compat_doit+0x22a/0x650 net/tipc/netlink_compat.c:390 1 lock held by syz.2.6968/25071: #0: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:641 [inline] #0: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3505 1 lock held by syz.2.6968/25073: #0: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: dev_ioctl+0x7a4/0x1150 net/core/dev_ioctl.c:815 4 locks held by dhcpcd-run-hook/25080: #0: ffff888028dda450 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: prepare_bprm_creds fs/exec.c:1362 [inline] #0: ffff888028dda450 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: bprm_execve+0xba/0x1510 fs/exec.c:1740 #1: ffff888028dda4d8 (&sig->exec_update_lock){++++}-{4:4}, at: exec_mmap+0xb2/0x4c0 fs/exec.c:857 #2: ffff88802bed1f30 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:536 [inline] #2: ffff88802bed1f30 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x2c2/0x9e0 mm/mmap.c:1308 #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1181 [inline] #3: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: is_module_text_address+0x1d/0x1e0 kernel/module/main.c:3921 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 40 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 17 Comm: pr/legacy Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:rdtsc_ordered arch/x86/include/asm/tsc.h:57 [inline] RIP: 0010:delay_tsc+0x71/0xc0 arch/x86/lib/delay.c:72 Code: 00 00 e8 32 de 5a f6 65 8b 05 8b 19 61 07 85 c0 74 1c f3 90 bf 01 00 00 00 e8 7b dc 5a f6 e8 b6 7b 01 00 39 c5 75 0e 0f 01 f9 <66> 90 eb bd e8 56 74 fa f5 eb dd 4c 29 fb e8 9c 7b 01 00 89 c5 0f RSP: 0018:ffffc900001679f0 EFLAGS: 00000246 RAX: 00000000a7d01914 RBX: 0000000000000899 RCX: 0000000000000001 RDX: 0000000000000261 RSI: ffffffff8bac2160 RDI: ffffffff8bac2120 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff8b390650 R12: 1ffffffff33c205a R13: 00000000ffffffff R14: 00000261a7d016d0 R15: 0000000000000180 FS: 0000000000000000(0000) GS:ffff888125d7e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f81decf1286 CR3: 000000001e7ec000 CR4: 00000000003526f0 Call Trace: udelay include/asm-generic/delay.h:62 [inline] wait_for_lsr+0x166/0x2f0 drivers/tty/serial/8250/8250_port.c:1988 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3229 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3294 [inline] serial8250_console_write+0x114b/0x1b50 drivers/tty/serial/8250/8250_port.c:3379 console_emit_next_record kernel/printk/printk.c:3163 [inline] console_flush_one_record+0x68b/0xb90 kernel/printk/printk.c:3269 legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3712 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245