INFO: task kworker/u8:3:56 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:3 state:D stack:21352 pid:56 tgid:56 ppid:2 task_flags:0x4248060 flags:0x00080000 Workqueue: xfs-cil/loop5 [ 770.364126][ T37] Workqueue: xfs-cil/loop5 xlog_cil_push_work Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x16dc/0x5500 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_timeout+0xc0/0x2c0 kernel/time/sleep_timeout.c:75 ___down_common kernel/locking/semaphore.c:293 [inline] __down_common+0x3b7/0x850 kernel/locking/semaphore.c:318 down+0x80/0xd0 kernel/locking/semaphore.c:100 xfs_buf_lock+0x153/0x4c0 fs/xfs/xfs_buf.c:932 xfs_buf_item_unpin+0x1bb/0x6c0 fs/xfs/xfs_buf_item.c:551 xlog_cil_ail_insert fs/xfs/xfs_log_cil.c:-1 [inline] xlog_cil_committed+0x9c6/0x1110 fs/xfs/xfs_log_cil.c:995 xlog_cil_push_work+0x24b6/0x2a90 fs/xfs/xfs_log_cil.c:1607 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 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 INFO: task syz.5.542:11936 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.542 state:D stack:21000 pid:11936 tgid:11935 ppid:11102 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x16dc/0x5500 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7607 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1670 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline] __rt_mutex_slowlock_locked+0x1f84/0x25b0 kernel/locking/rtmutex.c:1787 __rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114 rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline] __down_read kernel/locking/rwsem.c:1502 [inline] down_read_nested+0x136/0x200 kernel/locking/rwsem.c:1710 xfs_ilock+0x109/0x380 fs/xfs/xfs_inode.c:152 xfs_ilock_iocb fs/xfs/xfs_file.c:196 [inline] xfs_ilock_iocb_for_write fs/xfs/xfs_file.c:210 [inline] xfs_file_dio_write_aligned+0x12b/0x480 fs/xfs/xfs_file.c:761 xfs_file_dio_write fs/xfs/xfs_file.c:989 [inline] xfs_file_write_iter+0x7f4/0x940 fs/xfs/xfs_file.c:1201 iter_file_splice_write+0xa36/0x1240 fs/splice.c:736 do_splice_from fs/splice.c:936 [inline] direct_splice_actor+0x104/0x160 fs/splice.c:1159 splice_direct_to_actor+0x586/0xcc0 fs/splice.c:1103 do_splice_direct_actor fs/splice.c:1202 [inline] do_splice_direct+0x19b/0x2a0 fs/splice.c:1228 do_sendfile+0x540/0x7e0 fs/read_write.c:1371 __do_sys_sendfile64 fs/read_write.c:1432 [inline] __se_sys_sendfile64+0x144/0x1a0 fs/read_write.c:1418 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: 0033:0x7efcbe46e0d9 RSP: 002b:00007efcbc6c6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007efcbe6f5fa0 RCX: 00007efcbe46e0d9 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000004 RBP: 00007efcbe505024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000020fffe82 R11: 0000000000000246 R12: 0000000000000000 R13: 00007efcbe6f6038 R14: 00007efcbe6f5fa0 R15: 00007ffdf225e278 INFO: task syz.5.542:11950 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.542 state:D stack:25672 pid:11950 tgid:11935 ppid:11102 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x16dc/0x5500 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_timeout+0xc0/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2ca/0x5e0 kernel/sched/completion.c:153 __flush_workqueue+0x709/0x1470 kernel/workqueue.c:4130 xlog_cil_push_now fs/xfs/xfs_log_cil.c:1725 [inline] xlog_cil_force_seq+0x21a/0x880 fs/xfs/xfs_log_cil.c:1927 xfs_log_force_seq+0x196/0x440 fs/xfs/xfs_log.c:2984 __xfs_trans_commit+0x7f7/0xc20 fs/xfs/xfs_trans.c:877 xfs_trans_commit+0x13e/0x1c0 fs/xfs/xfs_trans.c:926 xfs_sync_sb_buf+0x13f/0x230 fs/xfs/libxfs/xfs_sb.c:1490 xfs_ioc_setlabel+0x1d7/0x340 fs/xfs/xfs_ioctl.c:1081 xfs_file_ioctl+0x901/0x1590 fs/xfs/xfs_ioctl.c:1238 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xff/0x170 fs/ioctl.c:583 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: 0033:0x7efcbe46e0d9 RSP: 002b:00007efcbc6a5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007efcbe6f6090 RCX: 00007efcbe46e0d9 RDX: 0000200000000080 RSI: 0000000041009432 RDI: 000000000000000a RBP: 00007efcbe505024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007efcbe6f6128 R14: 00007efcbe6f6090 R15: 00007ffdf225e278 INFO: task syz.5.542:11951 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.542 state:D stack:27952 pid:11951 tgid:11935 ppid:11102 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x16dc/0x5500 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_timeout+0xc0/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2ca/0x5e0 kernel/sched/completion.c:153 __flush_workqueue+0x709/0x1470 kernel/workqueue.c:4130 xlog_cil_push_now fs/xfs/xfs_log_cil.c:1725 [inline] xlog_cil_force_seq+0x21a/0x880 fs/xfs/xfs_log_cil.c:1927 xfs_log_force_seq+0x196/0x440 fs/xfs/xfs_log.c:2984 __xfs_trans_commit+0x7f7/0xc20 fs/xfs/xfs_trans.c:877 xfs_trans_commit+0x13e/0x1c0 fs/xfs/xfs_trans.c:926 xfs_link+0x63d/0x870 fs/xfs/xfs_inode.c:972 xfs_vn_link+0x183/0x280 fs/xfs/xfs_iops.c:394 vfs_link+0x491/0x650 fs/namei.c:5791 filename_linkat+0x26d/0x5f0 fs/namei.c:5859 __do_sys_linkat fs/namei.c:5885 [inline] __se_sys_linkat+0x60/0x2d0 fs/namei.c:5880 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: 0033:0x7efcbe46e0d9 RSP: 002b:00007efcbc684028 EFLAGS: 00000246 ORIG_RAX: 0000000000000109 RAX: ffffffffffffffda RBX: 00007efcbe6f6180 RCX: 00007efcbe46e0d9 RDX: ffffffffffffff9c RSI: 00002000000006c0 RDI: ffffffffffffff9c RBP: 00007efcbe505024 R08: 0000000000001000 R09: 0000000000000000 R10: 0000200000000100 R11: 0000000000000246 R12: 0000000000000000 R13: 00007efcbe6f6218 R14: 00007efcbe6f6180 R15: 00007ffdf225e278 Showing all locks held in the system: 2 locks held by kworker/0:0/9: #0: ffff88801daa2538 ((wq_completion)inet_frag_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88801daa2538 ((wq_completion)inet_frag_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc900000e7c40 ((work_completion)(&fqdir->destroy_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc900000e7c40 ((work_completion)(&fqdir->destroy_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 2 locks held by kworker/u8:0/12: #0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90000117c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90000117c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 4 locks held by pr/legacy/17: 1 lock held by khungtaskd/37: #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:3/56: #0: ffff88802f7bc138 ((wq_completion)xfs-cil/loop5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88802f7bc138 ((wq_completion)xfs-cil/loop5){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc9000122fc40 ((work_completion)(&ctx->push_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000122fc40 ((work_completion)(&ctx->push_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 3 locks held by kworker/u8:6/155: #0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc900038c7c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc900038c7c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313 3 locks held by kworker/u8:12/1180: #0: ffff8880321bf938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff8880321bf938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc900060cfc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc900060cfc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x123/0x16e0 net/ipv6/addrconf.c:4229 4 locks held by kworker/u8:20/3394: #0: ffff88801aea0938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88801aea0938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc9000e897c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000e897c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff8f59d8a0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:673 #3: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: fib6_rules_net_exit_batch+0x20/0xc0 net/ipv6/fib6_rules.c:645 2 locks held by klogd/4944: 2 locks held by dhcpcd/5251: #0: ffff88803d80a928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xe7/0xee0 net/netlink/af_netlink.c:2273 #1: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dump_ifinfo+0xa74/0x14b0 net/core/rtnetlink.c:2562 2 locks held by getty/5343: #0: ffff888035eee0a0 (&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+0x460/0x1360 drivers/tty/n_tty.c:2211 2 locks held by kworker/1:8/6798: #0: ffff888060fd0d38 ((wq_completion)xfs-sync/loop5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff888060fd0d38 ((wq_completion)xfs-sync/loop5){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90005ccfc40 ((work_completion)(&(&log->l_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90005ccfc40 ((work_completion)(&(&log->l_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 2 locks held by kworker/1:10/8608: #0: ffff88813ff1b938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88813ff1b938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90004927c40 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90004927c40 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 1 lock held by udevd/11824: 2 locks held by syz.5.542/11936: #0: ffff88802512c500 (sb_writers#23){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1158 #1: ffff88805f843680 (&sb->s_type->i_mutex_key#34){++++}-{4:4}, at: xfs_ilock+0x109/0x380 fs/xfs/xfs_inode.c:152 1 lock held by syz.5.542/11950: #0: ffff88802512c500 (sb_writers#23){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:538 5 locks held by syz.5.542/11951: #0: ffff88802512c500 (sb_writers#23){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff88805fa37a80 (&inode->i_sb->s_type->i_mutex_dir_key/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff88805fa37a80 (&inode->i_sb->s_type->i_mutex_dir_key/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff88805fa37a80 (&inode->i_sb->s_type->i_mutex_dir_key/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff88805fa37a80 (&inode->i_sb->s_type->i_mutex_dir_key/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4955 #2: ffff88805f843680 (&sb->s_type->i_mutex_key#34){++++}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline] #2: ffff88805f843680 (&sb->s_type->i_mutex_key#34){++++}-{4:4}, at: vfs_link+0x349/0x650 fs/namei.c:5780 #3: ffff88805fa377f8 (&xfs_dir_ilock_class){++++}-{4:4}, at: xfs_lock_two_inodes+0xb6/0x310 fs/xfs/xfs_inode.c:506 #4: ffff88805f8433f8 (&xfs_nondir_ilock_class/1){+.+.}-{4:4}, at: xfs_trans_alloc_dir+0x154/0x620 fs/xfs/xfs_trans.c:1390 8 locks held by syz-executor/13079: 1 lock held by syz-executor/13101: 1 lock held by syz-executor/13626: #0: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4158 2 locks held by syz.0.761/13859: 1 lock held by syz-executor/13872: #0: ffff88813ff67238 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_dop_revalidate+0x9e/0x650 fs/kernfs/dir.c:1217 2 locks held by syz.1.762/13875: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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+0xfd7/0x1030 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 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3801 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3821 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3876 [inline] RIP: 0010:__lock_acquire+0xab5/0x2ce0 kernel/locking/lockdep.c:5237 Code: 42 11 0e 48 c7 c6 9d f6 99 8d 67 48 0f b9 3a 90 48 bb eb 83 b5 80 46 86 c8 61 48 0f af dd 48 c1 eb 2d 48 8b 04 dd 00 55 61 93 <48> 85 c0 74 1c 48 83 c0 f8 74 16 48 8b 48 18 48 39 e9 0f 84 bb 01 RSP: 0018:ffffc90000167370 EFLAGS: 00000002 RAX: ffffffff93a77fb8 RBX: 000000000003bbf4 RCX: 0000000000040000 RDX: 00000000ee9f9cf0 RSI: 0000000036f756d1 RDI: ffff88801cae5d00 RBP: c85e0a36d7f4549b R08: ffffffff84cdb808 R09: 0000000000080000 R10: 0000000000000000 R11: ffffffff99cf7890 R12: ffff88801cae6a20 R13: ffff88801cae6a20 R14: ffff88801cae5d00 R15: 0000000000000007 FS: 0000000000000000(0000) GS:ffff888125d46000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0769538a10 CR3: 000000003c372000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 debug_object_activate+0xa8/0x3b0 lib/debugobjects.c:873 debug_hrtimer_activate kernel/time/hrtimer.c:485 [inline] debug_activate kernel/time/hrtimer.c:528 [inline] remove_and_enqueue_same_base kernel/time/hrtimer.c:1259 [inline] __hrtimer_start_range_ns kernel/time/hrtimer.c:1402 [inline] hrtimer_start_range_ns_common+0x4c4/0xb90 kernel/time/hrtimer.c:1481 hrtimer_start_range_ns+0x111/0x3f0 kernel/time/hrtimer.c:1503 enqueue_task+0x75/0x410 kernel/sched/core.c:2184 sched_change_end+0x213/0x600 kernel/sched/core.c:11255 migrate_disable_switch kernel/sched/core.c:2465 [inline] __schedule+0x1879/0x5500 kernel/sched/core.c:7089 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7556 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:408 Code: 1f 70 fc 44 89 f9 d3 e5 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 7c 95 d9 fc 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d e9 57 98 f1 05 cc 44 89 f9 80 e1 07 38 c1 RSP: 0018:ffffc90000167a70 EFLAGS: 00000202 RAX: 0000000000000037 RBX: 0000000000000037 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000000003f8 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff8555a8c0 R12: dffffc0000000000 R13: ffffffff99e462c0 R14: ffffffff99e46340 R15: 0000000000000000 serial_port_out include/linux/serial_core.h:813 [inline] serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3245 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline] serial8250_console_write+0x1201/0x1b40 drivers/tty/serial/8250/8250_port.c:3385 console_emit_next_record kernel/printk/printk.c:3163 [inline] console_flush_one_record+0x642/0xb50 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