INFO: task syz.4.24:6052 blocked for more than 143 seconds.
Not tainted 6.15.0-rc7-syzkaller-00082-g5cdb2c77c4c3 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.24 state:D stack:28952 pid:6052 tgid:6045 ppid:5817 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
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:902 [inline]
lock_rename fs/namei.c:3265 [inline]
do_renameat2+0x3dd/0xc50 fs/namei.c:5216
__do_sys_rename fs/namei.c:5317 [inline]
__se_sys_rename fs/namei.c:5315 [inline]
__x64_sys_rename+0x82/0x90 fs/namei.c:5315
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbc10d8e969
RSP: 002b:00007fbc0ebd5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007fbc10fb6080 RCX: 00007fbc10d8e969
RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000200000000000
RBP: 00007fbc10e10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fbc10fb6080 R15: 00007ffe85db4818
Showing all locks held in the system:
2 locks held by kworker/u8:0/12:
#0: ffff88801c31c148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801c31c148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90000117c60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000117c60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
1 lock held by khungtaskd/31:
#0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
4 locks held by kworker/u8:4/62:
#0: ffff88801da8b948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801da8b948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9000154fc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000154fc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffff8880754020e0 (&type->s_umount_key#82){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562
#3: ffff888079fe2fe0 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
3 locks held by kworker/u9:1/5129:
#0: ffff8880247cb148 ((wq_completion)hci3){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff8880247cb148 ((wq_completion)hci3){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9000e24fc60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000e24fc60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffff88807efccd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331
2 locks held by getty/5579:
#0: ffff88814d5150a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036cb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by syz.4.24/6046:
2 locks held by syz.4.24/6052:
#0: ffff888075402420 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
#1: ffff888079fe3390 (&type->i_mutex_dir_key#16/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline]
#1: ffff888079fe3390 (&type->i_mutex_dir_key#16/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3265 [inline]
#1: ffff888079fe3390 (&type->i_mutex_dir_key#16/1){+.+.}-{4:4}, at: do_renameat2+0x3dd/0xc50 fs/namei.c:5216
2 locks held by syz.5.79/6485:
#0: ffff8880754020e0 (&type->s_umount_key#82){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880754020e0 (&type->s_umount_key#82){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120
#1: ffff8880246267d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff8880246267d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc7-syzkaller-00082-g5cdb2c77c4c3 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
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: 5827 Comm: kworker/u9:4 Not tainted 6.15.0-rc7-syzkaller-00082-g5cdb2c77c4c3 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: hci3 hci_cmd_timeout
RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:416
Code: e8 88 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 9c bd e8 fc 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d e9 87 3e 1b 06 cc 44 89 f9 80 e1 07 38 c1
RSP: 0018:ffffc9000443f3b0 EFLAGS: 00000002
RAX: 0000000000000036 RBX: 0000000000000036 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020
RBP: 00000000000003f8 R08: ffff888024138237 R09: 1ffff11004827046
R10: dffffc0000000000 R11: ffffffff85370850 R12: dffffc0000000000
R13: ffffffff9981cc4c R14: ffffffff99b21a00 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881261f6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005573a4414168 CR3: 0000000057f34000 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:3306 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline]
serial8250_console_write+0x1410/0x1ba0 drivers/tty/serial/8250/8250_port.c:3456
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x728/0xc40 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+0xd8/0x1e0 net/bluetooth/hci_core.c:1453
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245