INFO: task syz.7.216:7898 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.216       state:D stack:24104 pid:7898  tgid:7885  ppid:6316   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5504 [inline]
 __schedule+0x16dc/0x5500 kernel/sched/core.c:7228
 __schedule_loop kernel/sched/core.c:7307 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7603
 rwbase_write_lock+0x3cf/0x720 kernel/locking/rwbase_rt.c:279
 inode_lock_nested include/linux/fs.h:1074 [inline]
 __start_dirop fs/namei.c:2918 [inline]
 start_dirop fs/namei.c:2942 [inline]
 filename_create+0x200/0x370 fs/namei.c:4951
 filename_mkdirat+0xd2/0x520 fs/namei.c:5298
 __do_sys_mkdir fs/namei.c:5332 [inline]
 __se_sys_mkdir+0x34/0x150 fs/namei.c:5329
 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: 0033:0x7f640084ce59
RSP: 002b:00007f63fea5c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f6400ac6180 RCX: 00007f640084ce59
RDX: 0000000000000000 RSI: 0000000000000022 RDI: 0000200000000300
RBP: 00007f64008e2e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6400ac6218 R14: 00007f6400ac6180 R15: 00007ffc93ce4b18
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 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 05/09/2026
RIP: 0010:delay_tsc+0x97/0xc0 arch/x86/lib/delay.c:96
Code: 0e 0f 01 f9 66 90 eb bd e8 36 33 13 f6 eb dd 4c 29 fb e8 0c 86 01 00 89 c5 0f 01 f9 66 90 49 89 d6 49 c1 e6 20 49 09 c6 eb d7 <bf> 01 00 00 00 e8 1f 86 73 f6 65 8b 05 f8 e3 4d 07 85 c0 74 0c 5b
RSP: 0018:ffffc90000167a08 EFLAGS: 00000216
RAX: 00000000009654e0 RBX: 0000000000000899 RCX: 0000000000000000
RDX: 0000000000000091 RSI: ffffffff8ba7ef80 RDI: ffffffff8ba7ef40
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff8b1fdb90 R12: 1ffffffff3368f92
R13: 00000000ffffffff R14: 0000009100964c08 R15: 00000000000008d8
FS:  0000000000000000(0000) GS:ffff888126144000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f02ef71cd58 CR3: 000000005f43a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 udelay include/asm-generic/delay.h:62 [inline]
 wait_for_lsr+0x14d/0x300 drivers/tty/serial/8250/8250_port.c:1979
 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3210 [inline]
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3275 [inline]
 serial8250_console_write+0x1232/0x1bd0 drivers/tty/serial/8250/8250_port.c:3360
 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
 </TASK>