INFO: task syz.0.16:6572 blocked for more than 143 seconds.
Not tainted 6.16.0-syzkaller-00684-ge5cf61fa6e2f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.16 state:D stack:25672 pid:6572 tgid:6570 ppid:6435 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6879
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936
rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write_nested+0x1b5/0x200 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:914 [inline]
lock_two_directories+0x16b/0x220 fs/namei.c:3243
lock_rename fs/namei.c:3277 [inline]
do_renameat2+0x36f/0xa80 fs/namei.c:5224
__do_sys_renameat2 fs/namei.c:5312 [inline]
__se_sys_renameat2 fs/namei.c:5309 [inline]
__x64_sys_renameat2+0xce/0xe0 fs/namei.c:5309
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8d4e78e929
RSP: 002b:00007f8d4f673038 EFLAGS: 00000246 ORIG_RAX: 000000000000013c
RAX: ffffffffffffffda RBX: 00007f8d4e9b5fa0 RCX: 00007f8d4e78e929
RDX: ffffffffffffff9c RSI: 0000200000000580 RDI: ffffffffffffff9c
RBP: 00007f8d4e810b39 R08: 0000000000000000 R09: 0000000000000000
R10: 00002000000005c0 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8d4e9b5fa0 R15: 00007ffcb56d5d38
Showing all locks held in the system:
3 locks held by kworker/0:0/9:
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc900000e7bc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900000e7bc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff88802a5c9240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490
1 lock held by khungtaskd/31:
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
1 lock held by klogd/5194:
#0: ffff8880b8639e18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
2 locks held by getty/5597:
#0: ffff8880316be0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by syz.0.16/6572:
#0: ffff88807eea4428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88807eea4738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: lock_rename fs/namei.c:3276 [inline]
#1: ffff88807eea4738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: do_renameat2+0x364/0xa80 fs/namei.c:5224
#2: ffff8880772d1c60 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#2: ffff8880772d1c60 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: lock_two_directories+0x141/0x220 fs/namei.c:3242
#3: ffff8880772d1c60 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#3: ffff8880772d1c60 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: lock_two_directories+0x16b/0x220 fs/namei.c:3243
4 locks held by syz.1.17/6753:
#0: ffff8880786aa428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff8880786aa738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: lock_rename fs/namei.c:3276 [inline]
#1: ffff8880786aa738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: do_renameat2+0x364/0xa80 fs/namei.c:5224
#2: ffff8880771e95f0 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#2: ffff8880771e95f0 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: lock_two_directories+0x141/0x220 fs/namei.c:3242
#3: ffff8880771e95f0 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#3: ffff8880771e95f0 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: lock_two_directories+0x16b/0x220 fs/namei.c:3243
4 locks held by syz.2.18/6775:
#0: ffff888076b6c428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff888076b6c738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: lock_rename fs/namei.c:3276 [inline]
#1: ffff888076b6c738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: do_renameat2+0x364/0xa80 fs/namei.c:5224
#2: ffff8880771ebc90 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#2: ffff8880771ebc90 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: lock_two_directories+0x141/0x220 fs/namei.c:3242
#3: ffff8880771ebc90 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#3: ffff8880771ebc90 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: lock_two_directories+0x16b/0x220 fs/namei.c:3243
4 locks held by syz.3.19/6804:
#0: ffff88807c1d2428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88807c1d2738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: lock_rename fs/namei.c:3276 [inline]
#1: ffff88807c1d2738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: do_renameat2+0x364/0xa80 fs/namei.c:5224
#2: ffff8880772d4970 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#2: ffff8880772d4970 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: lock_two_directories+0x141/0x220 fs/namei.c:3242
#3: ffff8880772d4970 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#3: ffff8880772d4970 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: lock_two_directories+0x16b/0x220 fs/namei.c:3243
4 locks held by syz.4.20/6832:
#0: ffff888028e54428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff888028e54738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: lock_rename fs/namei.c:3276 [inline]
#1: ffff888028e54738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: do_renameat2+0x364/0xa80 fs/namei.c:5224
#2: ffff8880772d69a0 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#2: ffff8880772d69a0 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: lock_two_directories+0x141/0x220 fs/namei.c:3242
#3: ffff8880772d69a0 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#3: ffff8880772d69a0 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: lock_two_directories+0x16b/0x220 fs/namei.c:3243
4 locks held by syz.5.21/6861:
#0: ffff888066c58428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff888066c58738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: lock_rename fs/namei.c:3276 [inline]
#1: ffff888066c58738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: do_renameat2+0x364/0xa80 fs/namei.c:5224
#2: ffff888077358f80 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#2: ffff888077358f80 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: lock_two_directories+0x141/0x220 fs/namei.c:3242
#3: ffff888077358f80 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#3: ffff888077358f80 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: lock_two_directories+0x16b/0x220 fs/namei.c:3243
4 locks held by syz.6.22/6889:
#0: ffff888058202428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff888058202738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: lock_rename fs/namei.c:3276 [inline]
#1: ffff888058202738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: do_renameat2+0x364/0xa80 fs/namei.c:5224
#2: ffff8880771ee9a0 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#2: ffff8880771ee9a0 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: lock_two_directories+0x141/0x220 fs/namei.c:3242
#3: ffff8880771ee9a0 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#3: ffff8880771ee9a0 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: lock_two_directories+0x16b/0x220 fs/namei.c:3243
4 locks held by syz.7.23/6924:
#0: ffff8880589ce428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff8880589ce738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: lock_rename fs/namei.c:3276 [inline]
#1: ffff8880589ce738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: do_renameat2+0x364/0xa80 fs/namei.c:5224
#2: ffff8880614195f0 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#2: ffff8880614195f0 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: lock_two_directories+0x141/0x220 fs/namei.c:3242
#3: ffff8880614195f0 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#3: ffff8880614195f0 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: lock_two_directories+0x16b/0x220 fs/namei.c:3243
4 locks held by syz.8.24/6953:
#0: ffff88807a6fa428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88807a6fa738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: lock_rename fs/namei.c:3276 [inline]
#1: ffff88807a6fa738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: do_renameat2+0x364/0xa80 fs/namei.c:5224
#2: ffff88806141b620 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#2: ffff88806141b620 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: lock_two_directories+0x141/0x220 fs/namei.c:3242
#3: ffff88806141b620 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#3: ffff88806141b620 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: lock_two_directories+0x16b/0x220 fs/namei.c:3243
4 locks held by syz.9.25/6983:
#0: ffff8880634fe428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff8880634fe738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: lock_rename fs/namei.c:3276 [inline]
#1: ffff8880634fe738 (&type->s_vfs_rename_key){+.+.}-{4:4}, at: do_renameat2+0x364/0xa80 fs/namei.c:5224
#2: ffff88806141dcc0 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#2: ffff88806141dcc0 (&sb->s_type->i_mutex_key#20/1){+.+.}-{4:4}, at: lock_two_directories+0x141/0x220 fs/namei.c:3242
#3: ffff88806141dcc0 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#3: ffff88806141dcc0 (&sb->s_type->i_mutex_key#21/5){+.+.}-{4:4}, at: lock_two_directories+0x16b/0x220 fs/namei.c:3243
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-syzkaller-00684-ge5cf61fa6e2f #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5155 Comm: kworker/u9:1 Not tainted 6.16.0-syzkaller-00684-ge5cf61fa6e2f #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: hci9 hci_cmd_timeout
RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:416
Code: 1f 7d fc 44 89 f9 d3 e5 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 dc 09 dd fc 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d e9 17 3c 2a 06 cc 44 89 f9 80 e1 07 38 c1
RSP: 0018:ffffc9000f657310 EFLAGS: 00000002
RAX: 0000000000000020 RBX: 0000000000000020 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020
RBP: 00000000000003f8 R08: ffff888024c30237 R09: 1ffff11004986046
R10: dffffc0000000000 R11: ffffffff85431680 R12: dffffc0000000000
R13: ffffffff99ad689c R14: ffffffff99ddb220 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125c3e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e75ffff CR3: 0000000033e6a000 CR4: 00000000003526f0
Call Trace:
serial_port_out include/linux/serial_core.h:798 [inline]
serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3306 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline]
serial8250_console_write+0x140d/0x1ba0 drivers/tty/serial/8250/8250_port.c:3456
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x725/0xc40 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
_printk+0xcf/0x120 kernel/printk/printk.c:2475
bt_err+0x10b/0x160 net/bluetooth/lib.c:296
hci_cmd_timeout+0xff/0x1e0 net/bluetooth/hci_core.c:1475
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245