Bluetooth: hci5: Opcode 0x0406 failed: -4
Bluetooth: hci7: Opcode 0x0c1a failed: -4
Bluetooth: hci7: Opcode 0x0406 failed: -4
Bluetooth: hci7: Opcode 0x0406 failed: -4
Freezing user space processes
------------[ cut here ]------------
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.3.784/7838 is trying to acquire lock:
ffffffff8cb21a80 (console_owner){..-.}-{0:0}, at: console_lock_spinning_enable kernel/printk/printk.c:1818 [inline]
ffffffff8cb21a80 (console_owner){..-.}-{0:0}, at: console_emit_next_record+0x68f/0xb50 kernel/printk/printk.c:2774

but task is already holding lock:
ffff888018bac618 (&p->pi_lock){-.-.}-{2:2}, at: task_call_func+0x3f/0x260 kernel/sched/core.c:4293

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&p->pi_lock){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
       try_to_wake_up+0x5a/0x10b0 kernel/sched/core.c:4112
       __wake_up_common+0x28e/0x4d0 kernel/sched/wait.c:107
       __wake_up_common_lock kernel/sched/wait.c:138 [inline]
       __wake_up+0x121/0x1a0 kernel/sched/wait.c:160
       pty_unthrottle+0x38/0x60 drivers/tty/pty.c:95
       tty_unthrottle_safe+0x109/0x160 drivers/tty/tty_ioctl.c:179
       n_tty_receive_buf_common+0x10d5/0x1470 drivers/tty/n_tty.c:1736
       tty_port_default_receive_buf+0x69/0x90 drivers/tty/tty_port.c:39
       receive_buf drivers/tty/tty_buffer.c:515 [inline]
       flush_to_ldisc+0x2b9/0x800 drivers/tty/tty_buffer.c:565
       process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
       worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
       kthread+0x29d/0x330 kernel/kthread.c:376
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

-> #2 (&tty->write_wait){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
       __wake_up_common_lock kernel/sched/wait.c:137 [inline]
       __wake_up+0x107/0x1a0 kernel/sched/wait.c:160
       tty_port_default_wakeup+0x9e/0xf0 drivers/tty/tty_port.c:71
       serial8250_tx_chars+0x615/0x800 drivers/tty/serial/8250/8250_port.c:1854
       serial8250_handle_irq+0x6b0/0x8b0 drivers/tty/serial/8250/8250_port.c:1968
       serial8250_default_handle_irq+0xb4/0x1a0 drivers/tty/serial/8250/8250_port.c:1988
       serial8250_interrupt+0x9b/0x1c0 drivers/tty/serial/8250/8250_core.c:126
       __handle_irq_event_percpu+0x293/0xa50 kernel/irq/handle.c:158
       handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
       handle_irq_event+0x87/0x1e0 kernel/irq/handle.c:210
       handle_edge_irq+0x242/0xb20 kernel/irq/chip.c:819
       generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
       handle_irq arch/x86/kernel/irq.c:233 [inline]
       __common_interrupt+0xd7/0x1e0 arch/x86/kernel/irq.c:252
       common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:242
       asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:682
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
       _raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194
       spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
       uart_write+0x67a/0x900 drivers/tty/serial/serial_core.c:601
       process_output_block drivers/tty/n_tty.c:586 [inline]
       n_tty_write+0xd61/0x11e0 drivers/tty/n_tty.c:2377
       do_tty_write drivers/tty/tty_io.c:1018 [inline]
       file_tty_write+0x4c7/0x840 drivers/tty/tty_io.c:1089
       call_write_iter include/linux/fs.h:2271 [inline]
       new_sync_write fs/read_write.c:491 [inline]
       vfs_write+0x482/0x9a0 fs/read_write.c:584
       ksys_write+0x14d/0x260 fs/read_write.c:637
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (&port_lock_key){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
       serial8250_console_write+0x17d/0x18b0 drivers/tty/serial/8250/8250_port.c:3445
       call_console_driver kernel/printk/printk.c:1977 [inline]
       console_emit_next_record+0x795/0xb50 kernel/printk/printk.c:2777
       console_flush_all kernel/printk/printk.c:-1 [inline]
       console_unlock+0x223/0x630 kernel/printk/printk.c:2906
       vprintk_emit+0x4b3/0x6a0 kernel/printk/printk.c:2303
       _printk+0xda/0x130 kernel/printk/printk.c:2328
       register_console+0x6bd/0x9b0 kernel/printk/printk.c:3269
       univ8250_console_init+0x41/0x43 drivers/tty/serial/8250/8250_core.c:687
       console_init+0x1bc/0x78e kernel/printk/printk.c:3359
       start_kernel+0x2f3/0x50d init/main.c:1049
       secondary_startup_64_no_verify+0xcf/0xdb

-> #0 (console_owner){..-.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3162 [inline]
       check_prevs_add kernel/locking/lockdep.c:3281 [inline]
       validate_chain kernel/locking/lockdep.c:3897 [inline]
       __lock_acquire+0x3a03/0x7ea0 kernel/locking/lockdep.c:5171
       lock_acquire+0x1bc/0x4a0 kernel/locking/lockdep.c:5790
       console_lock_spinning_enable kernel/printk/printk.c:1818 [inline]
       console_emit_next_record+0x6b0/0xb50 kernel/printk/printk.c:2774
       console_flush_all kernel/printk/printk.c:-1 [inline]
       console_unlock+0x223/0x630 kernel/printk/printk.c:2906
       vprintk_emit+0x4b3/0x6a0 kernel/printk/printk.c:2303
       _printk+0xda/0x130 kernel/printk/printk.c:2328
       __report_bug lib/bug.c:195 [inline]
       report_bug+0x34a/0x4f0 lib/bug.c:219
       handle_bug+0x3a/0x70 arch/x86/kernel/traps.c:324
       exc_invalid_op+0x16/0x40 arch/x86/kernel/traps.c:345
       asm_exc_invalid_op+0x16/0x20 arch/x86/include/asm/idtentry.h:606
       __set_task_frozen+0x1e9/0x290 kernel/freezer.c:129
       task_call_func+0x19e/0x260 kernel/sched/core.c:4308
       __freeze_task kernel/freezer.c:139 [inline]
       freeze_task+0x213/0x3a0 kernel/freezer.c:158
       try_to_freeze_tasks+0x190/0x600 kernel/power/process.c:54
       freeze_processes+0xc5/0x1e0 kernel/power/process.c:137
       suspend_freeze_processes kernel/power/power.h:257 [inline]
       suspend_prepare kernel/power/suspend.c:372 [inline]
       enter_state kernel/power/suspend.c:589 [inline]
       pm_suspend+0x289/0x9a0 kernel/power/suspend.c:626
       state_store+0x202/0x290 kernel/power/main.c:639
       kernfs_fop_write_iter+0x3a0/0x520 fs/kernfs/file.c:352
       call_write_iter include/linux/fs.h:2271 [inline]
       new_sync_write fs/read_write.c:491 [inline]
       vfs_write+0x482/0x9a0 fs/read_write.c:584
       ksys_write+0x14d/0x260 fs/read_write.c:637
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Chain exists of:
  console_owner --> &tty->write_wait --> &p->pi_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&p->pi_lock);
                               lock(&tty->write_wait);
                               lock(&p->pi_lock);
  lock(console_owner);

 *** DEADLOCK ***

9 locks held by syz.3.784/7838:
 #0: ffff88805ccc59e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038
 #1: ffff88802e9ae460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580
 #2: ffff888056f0ac88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1d8/0x520 fs/kernfs/file.c:343
 #3: ffff888017687830 (kn->active#74){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #3: ffff888017687830 (kn->active#74){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x520 fs/kernfs/file.c:344
 #4: ffffffff8c9e2aa8 (system_transition_mutex){+.+.}-{3:3}, at: enter_state kernel/power/suspend.c:575 [inline]
 #4: ffffffff8c9e2aa8 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x11c/0x9a0 kernel/power/suspend.c:626
 #5: ffffffff8c80a058 (tasklist_lock){.+.+}-{2:2}, at: try_to_freeze_tasks+0xe5/0x600 kernel/power/process.c:52
 #6: ffffffff8cb40398 (freezer_lock){....}-{2:2}, at: freeze_task+0x7c/0x3a0 kernel/freezer.c:157
 #7: ffff888018bac618 (&p->pi_lock){-.-.}-{2:2}, at: task_call_func+0x3f/0x260 kernel/sched/core.c:4293
 #8: ffffffff8cb21b60 (console_lock){+.+.}-{0:0}, at: _printk+0xda/0x130 kernel/printk/printk.c:2328

stack backtrace:
CPU: 0 PID: 7838 Comm: syz.3.784 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 check_noncircular+0x2f8/0x400 kernel/locking/lockdep.c:2215
 check_prev_add kernel/locking/lockdep.c:3162 [inline]
 check_prevs_add kernel/locking/lockdep.c:3281 [inline]
 validate_chain kernel/locking/lockdep.c:3897 [inline]
 __lock_acquire+0x3a03/0x7ea0 kernel/locking/lockdep.c:5171
 lock_acquire+0x1bc/0x4a0 kernel/locking/lockdep.c:5790
 console_lock_spinning_enable kernel/printk/printk.c:1818 [inline]
 console_emit_next_record+0x6b0/0xb50 kernel/printk/printk.c:2774
 console_flush_all kernel/printk/printk.c:-1 [inline]
 console_unlock+0x223/0x630 kernel/printk/printk.c:2906
 vprintk_emit+0x4b3/0x6a0 kernel/printk/printk.c:2303
 _printk+0xda/0x130 kernel/printk/printk.c:2328
 __report_bug lib/bug.c:195 [inline]
 report_bug+0x34a/0x4f0 lib/bug.c:219
 handle_bug+0x3a/0x70 arch/x86/kernel/traps.c:324
 exc_invalid_op+0x16/0x40 arch/x86/kernel/traps.c:345
 asm_exc_invalid_op+0x16/0x20 arch/x86/include/asm/idtentry.h:606
RIP: 0010:__set_task_frozen+0x1e9/0x290 kernel/freezer.c:129
Code: 68 c7 03 00 80 00 00 bd 00 80 00 00 89 e8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 33 88 11 00 0f 0b e9 2c ff ff ff e8 27 88 11 00 <0f> 0b eb bf 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 38 fe ff ff 48 89
RSP: 0018:ffffc90004b77a50 EFLAGS: 00010046
RAX: ffffffff8170be59 RBX: ffff888018babc18 RCX: 0000000000080000
RDX: ffffc900229ea000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: 0000000000000003 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200096ef2c R12: 0000000000000000
R13: 1ffff11003175783 R14: ffff888018bac6d8 R15: dffffc0000000000
 task_call_func+0x19e/0x260 kernel/sched/core.c:4308
 __freeze_task kernel/freezer.c:139 [inline]
 freeze_task+0x213/0x3a0 kernel/freezer.c:158
 try_to_freeze_tasks+0x190/0x600 kernel/power/process.c:54
 freeze_processes+0xc5/0x1e0 kernel/power/process.c:137
 suspend_freeze_processes kernel/power/power.h:257 [inline]
 suspend_prepare kernel/power/suspend.c:372 [inline]
 enter_state kernel/power/suspend.c:589 [inline]
 pm_suspend+0x289/0x9a0 kernel/power/suspend.c:626
 state_store+0x202/0x290 kernel/power/main.c:639
 kernfs_fop_write_iter+0x3a0/0x520 fs/kernfs/file.c:352
 call_write_iter include/linux/fs.h:2271 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x482/0x9a0 fs/read_write.c:584
 ksys_write+0x14d/0x260 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f124e79e199
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f124f728028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f124ea25fa0 RCX: 00007f124e79e199
RDX: 0000000000000007 RSI: 00002000000001c0 RDI: 0000000000000003
RBP: 00007f124e8350b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f124ea26038 R14: 00007f124ea25fa0 R15: 00007ffe68a249e8
 </TASK>
WARNING: CPU: 0 PID: 7838 at kernel/freezer.c:129 __set_task_frozen+0x1e9/0x290 kernel/freezer.c:129
Modules linked in:
CPU: 0 PID: 7838 Comm: syz.3.784 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:__set_task_frozen+0x1e9/0x290 kernel/freezer.c:129
Code: 68 c7 03 00 80 00 00 bd 00 80 00 00 89 e8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 33 88 11 00 0f 0b e9 2c ff ff ff e8 27 88 11 00 <0f> 0b eb bf 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 38 fe ff ff 48 89
RSP: 0018:ffffc90004b77a50 EFLAGS: 00010046
RAX: ffffffff8170be59 RBX: ffff888018babc18 RCX: 0000000000080000
RDX: ffffc900229ea000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: 0000000000000003 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200096ef2c R12: 0000000000000000
R13: 1ffff11003175783 R14: ffff888018bac6d8 R15: dffffc0000000000
FS:  00007f124f7286c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ce33f720a0 CR3: 00000000419e7000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 3a810b1eb6134bdc DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 task_call_func+0x19e/0x260 kernel/sched/core.c:4308
 __freeze_task kernel/freezer.c:139 [inline]
 freeze_task+0x213/0x3a0 kernel/freezer.c:158
 try_to_freeze_tasks+0x190/0x600 kernel/power/process.c:54
 freeze_processes+0xc5/0x1e0 kernel/power/process.c:137
 suspend_freeze_processes kernel/power/power.h:257 [inline]
 suspend_prepare kernel/power/suspend.c:372 [inline]
 enter_state kernel/power/suspend.c:589 [inline]
 pm_suspend+0x289/0x9a0 kernel/power/suspend.c:626
 state_store+0x202/0x290 kernel/power/main.c:639
 kernfs_fop_write_iter+0x3a0/0x520 fs/kernfs/file.c:352
 call_write_iter include/linux/fs.h:2271 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x482/0x9a0 fs/read_write.c:584
 ksys_write+0x14d/0x260 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f124e79e199
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f124f728028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f124ea25fa0 RCX: 00007f124e79e199
RDX: 0000000000000007 RSI: 00002000000001c0 RDI: 0000000000000003
RBP: 00007f124e8350b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f124ea26038 R14: 00007f124ea25fa0 R15: 00007ffe68a249e8
 </TASK>