------------[ cut here ]------------
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz-executor/5824 is trying to acquire lock:
ffffffff8e6f53c0 (console_owner){-...}-{0:0}, at: console_lock_spinning_enable+0x61/0x80 kernel/printk/printk.c:1902

but task is already holding lock:
ffff8880b843b2e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:655 [inline]
ffff8880b843b2e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:639

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&rq->__lock){-.-.}-{2:2}:
       _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
       raw_spin_rq_lock_nested+0x2c/0x140 kernel/sched/core.c:647
       raw_spin_rq_lock kernel/sched/sched.h:1615 [inline]
       _task_rq_lock+0xcf/0x490 kernel/sched/core.c:747
       cgroup_move_task+0x81/0x2b0 kernel/sched/psi.c:1170
       css_set_move_task+0x285/0x600 kernel/cgroup/cgroup.c:948
       cgroup_post_fork+0x202/0x9b0 kernel/cgroup/cgroup.c:6910
       copy_process+0x5f26/0x7a10 kernel/fork.c:2467
       kernel_clone+0xfc/0x9a0 kernel/fork.c:2654
       user_mode_thread+0xcc/0x110 kernel/fork.c:2730
       rest_init+0x21/0x260 init/main.c:725
       start_kernel+0x47f/0x480 init/main.c:1210
       x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
       x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
       common_startup_64+0x13e/0x148

-> #3 (&p->pi_lock){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
       _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
       class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:570 [inline]
       try_to_wake_up+0xb2/0x1a80 kernel/sched/core.c:4130
       __wake_up_common+0x135/0x1f0 kernel/sched/wait.c:108
       __wake_up_common_lock kernel/sched/wait.c:125 [inline]
       __wake_up+0x31/0x60 kernel/sched/wait.c:146
       tty_port_default_wakeup+0x47/0x60 drivers/tty/tty_port.c:67
       serial8250_tx_chars+0x68f/0x860 drivers/tty/serial/8250/8250_port.c:1719
       serial8250_handle_irq+0x73e/0xcb0 drivers/tty/serial/8250/8250_port.c:1827
       serial8250_default_handle_irq+0x9e/0x270 drivers/tty/serial/8250/8250_port.c:1846
       serial8250_interrupt+0xf8/0x1d0 drivers/tty/serial/8250/8250_core.c:86
       __handle_irq_event_percpu+0x232/0x8e0 kernel/irq/handle.c:209
       handle_irq_event_percpu kernel/irq/handle.c:246 [inline]
       handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:263
       handle_edge_irq+0x375/0x970 kernel/irq/chip.c:855
       generic_handle_irq_desc include/linux/irqdesc.h:186 [inline]
       handle_irq arch/x86/kernel/irq.c:262 [inline]
       call_irq_handler arch/x86/kernel/irq.c:318 [inline]
       __common_interrupt+0xd8/0x2f0 arch/x86/kernel/irq.c:333
       common_interrupt+0xb9/0xe0 arch/x86/kernel/irq.c:326
       asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
       __sanitizer_cov_trace_switch+0x3b/0x90 kernel/kcov.c:350
       ma_pivots lib/maple_tree.c:602 [inline]
       mas_descend+0x88/0x4e0 lib/maple_tree.c:961
       mt_validate_nulls+0x2d6/0x9c0 lib/maple_tree.c:7120
       mt_validate+0x1f26/0x30b0 lib/maple_tree.c:7179
       validate_mm+0xa8/0x4e0 mm/vma.c:649
       __split_vma+0xa71/0xd90 mm/vma.c:567
       vms_gather_munmap_vmas+0x39f/0x1500 mm/vma.c:1429
       __mmap_setup mm/vma.c:2411 [inline]
       __mmap_region+0x492/0x29e0 mm/vma.c:2741
       mmap_region+0x180/0x3e0 mm/vma.c:2837
       do_mmap+0xc63/0x12f0 mm/mmap.c:559
       vm_mmap_pgoff+0x29e/0x470 mm/util.c:581
       ksys_mmap_pgoff+0x3c8/0x650 mm/mmap.c:605
       __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
       __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
       __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (&tty->write_wait){-.-.}-{3:3}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
       _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
       __wake_up_common_lock kernel/sched/wait.c:124 [inline]
       __wake_up+0x1c/0x60 kernel/sched/wait.c:146
       tty_port_default_wakeup+0x47/0x60 drivers/tty/tty_port.c:67
       serial8250_tx_chars+0x68f/0x860 drivers/tty/serial/8250/8250_port.c:1719
       serial8250_handle_irq+0x73e/0xcb0 drivers/tty/serial/8250/8250_port.c:1827
       serial8250_default_handle_irq+0x9e/0x270 drivers/tty/serial/8250/8250_port.c:1846
       serial8250_interrupt+0xf8/0x1d0 drivers/tty/serial/8250/8250_core.c:86
       __handle_irq_event_percpu+0x232/0x8e0 kernel/irq/handle.c:209
       handle_irq_event_percpu kernel/irq/handle.c:246 [inline]
       handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:263
       handle_edge_irq+0x375/0x970 kernel/irq/chip.c:855
       generic_handle_irq_desc include/linux/irqdesc.h:186 [inline]
       handle_irq arch/x86/kernel/irq.c:262 [inline]
       call_irq_handler arch/x86/kernel/irq.c:318 [inline]
       __common_interrupt+0xd8/0x2f0 arch/x86/kernel/irq.c:333
       common_interrupt+0xb9/0xe0 arch/x86/kernel/irq.c:326
       asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline]
       _raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
       spin_unlock_irqrestore include/linux/spinlock.h:407 [inline]
       uart_port_unlock_irqrestore include/linux/serial_core.h:788 [inline]
       uart_port_unlock_deref drivers/tty/serial/serial_core.c:91 [inline]
       uart_port_unlock_deref drivers/tty/serial/serial_core.c:88 [inline]
       uart_write+0x29d/0xb20 drivers/tty/serial/serial_core.c:634
       process_output_block drivers/tty/n_tty.c:557 [inline]
       n_tty_write+0x44f/0x12d0 drivers/tty/n_tty.c:2366
       iterate_tty_write drivers/tty/tty_io.c:1006 [inline]
       file_tty_write.isra.0+0x4d2/0x890 drivers/tty/tty_io.c:1081
       tty_write drivers/tty/tty_io.c:1102 [inline]
       redirected_tty_write drivers/tty/tty_io.c:1125 [inline]
       redirected_tty_write+0xd4/0x120 drivers/tty/tty_io.c:1105
       new_sync_write fs/read_write.c:595 [inline]
       vfs_write+0x6ac/0x1070 fs/read_write.c:688
       ksys_write+0x12a/0x250 fs/read_write.c:740
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&port_lock_key){-.-.}-{3:3}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
       _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
       uart_port_lock_irqsave include/linux/serial_core.h:717 [inline]
       serial8250_console_write+0x17e/0x1900 drivers/tty/serial/8250/8250_port.c:3301
       console_emit_next_record kernel/printk/printk.c:3183 [inline]
       console_flush_one_record+0x790/0xe50 kernel/printk/printk.c:3269
       console_flush_all kernel/printk/printk.c:3343 [inline]
       __console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
       console_unlock+0x103/0x260 kernel/printk/printk.c:3413
       vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479
       _printk+0xcf/0x110 kernel/printk/printk.c:2504
       register_console.cold+0xc0/0x248 kernel/printk/printk.c:4208
       univ8250_console_init+0x6f/0x80 drivers/tty/serial/8250/8250_core.c:515
       console_init+0x423/0x620 kernel/printk/printk.c:4407
       start_kernel+0x305/0x480 init/main.c:1147
       x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
       x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
       common_startup_64+0x13e/0x148

-> #0 (console_owner){-...}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3165 [inline]
       check_prevs_add kernel/locking/lockdep.c:3284 [inline]
       validate_chain kernel/locking/lockdep.c:3908 [inline]
       __lock_acquire+0x14b8/0x2630 kernel/locking/lockdep.c:5237
       lock_acquire kernel/locking/lockdep.c:5868 [inline]
       lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825
       console_lock_spinning_enable+0x72/0x80 kernel/printk/printk.c:1902
       console_emit_next_record kernel/printk/printk.c:3177 [inline]
       console_flush_one_record+0x739/0xe50 kernel/printk/printk.c:3269
       console_flush_all kernel/printk/printk.c:3343 [inline]
       __console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
       console_unlock+0x103/0x260 kernel/printk/printk.c:3413
       vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479
       _printk+0xcf/0x110 kernel/printk/printk.c:2504
       __report_bug.cold+0x15/0x137 lib/bug.c:243
       report_bug+0xb2/0x220 lib/bug.c:281
       handle_bug+0x16a/0x2a0 arch/x86/kernel/traps.c:435
       exc_invalid_op+0x17/0x50 arch/x86/kernel/traps.c:489
       asm_exc_invalid_op+0x1a/0x20 arch/x86/include/asm/idtentry.h:616
       lockdep_assert_rq_held kernel/sched/sched.h:1600 [inline]
       lockdep_assert_rq_held kernel/sched/sched.h:1597 [inline]
       update_rq_clock+0x40a/0xd20 kernel/sched/core.c:850
       pick_next_task kernel/sched/core.c:6129 [inline]
       __schedule+0x1b7d/0x6120 kernel/sched/core.c:6849
       __schedule_loop kernel/sched/core.c:6990 [inline]
       schedule+0xdd/0x390 kernel/sched/core.c:7005
       do_nanosleep+0x206/0x560 kernel/time/hrtimer.c:2124
       hrtimer_nanosleep+0x156/0x360 kernel/time/hrtimer.c:2171
       common_nsleep+0xa1/0xd0 kernel/time/posix-timers.c:1345
       __do_sys_clock_nanosleep kernel/time/posix-timers.c:1391 [inline]
       __se_sys_clock_nanosleep kernel/time/posix-timers.c:1368 [inline]
       __x64_sys_clock_nanosleep+0x336/0x480 kernel/time/posix-timers.c:1368
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  console_owner --> &p->pi_lock --> &rq->__lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&rq->__lock);
                               lock(&p->pi_lock);
                               lock(&rq->__lock);
  lock(console_owner);

 *** DEADLOCK ***

3 locks held by syz-executor/5824:
 #0: ffff8880b843b2e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:655 [inline]
 #0: ffff8880b843b2e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:639
 #1: ffffffff8e7d5800 (console_lock){+.+.}-{0:0}, at: _printk+0xcf/0x110 kernel/printk/printk.c:2504
 #2: ffffffff8e7d5878 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:317 [inline]
 #2: ffffffff8e7d5878 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:428 [inline]
 #2: ffffffff8e7d5878 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:291 [inline]
 #2: ffffffff8e7d5878 (console_srcu){....}-{0:0}, at: console_flush_one_record+0xfd/0xe50 kernel/printk/printk.c:3246

stack backtrace:
CPU: 0 UID: 0 PID: 5824 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_circular_bug.cold+0x178/0x1c7 kernel/locking/lockdep.c:2043
 check_noncircular+0x146/0x160 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3165 [inline]
 check_prevs_add kernel/locking/lockdep.c:3284 [inline]
 validate_chain kernel/locking/lockdep.c:3908 [inline]
 __lock_acquire+0x14b8/0x2630 kernel/locking/lockdep.c:5237
 lock_acquire kernel/locking/lockdep.c:5868 [inline]
 lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825
 console_lock_spinning_enable+0x72/0x80 kernel/printk/printk.c:1902
 console_emit_next_record kernel/printk/printk.c:3177 [inline]
 console_flush_one_record+0x739/0xe50 kernel/printk/printk.c:3269
 console_flush_all kernel/printk/printk.c:3343 [inline]
 __console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
 console_unlock+0x103/0x260 kernel/printk/printk.c:3413
 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479
 _printk+0xcf/0x110 kernel/printk/printk.c:2504
 __report_bug.cold+0x15/0x137 lib/bug.c:243
 report_bug+0xb2/0x220 lib/bug.c:281
 handle_bug+0x16a/0x2a0 arch/x86/kernel/traps.c:435
 exc_invalid_op+0x17/0x50 arch/x86/kernel/traps.c:489
 asm_exc_invalid_op+0x1a/0x20 arch/x86/include/asm/idtentry.h:616
RIP: 0010:lockdep_assert_rq_held kernel/sched/sched.h:1600 [inline]
RIP: 0010:lockdep_assert_rq_held kernel/sched/sched.h:1597 [inline]
RIP: 0010:update_rq_clock+0x40a/0xd20 kernel/sched/core.c:850
Code: ab 48 0b 00 00 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f e9 18 9f ba 09 a8 04 0f 84 df fc ff ff 90 0f 0b 90 e9 d6 fc ff ff 90 <0f> 0b 90 e9 92 fc ff ff 4c 8d 83 40 0b 00 00 48 b8 00 00 00 00 00
RSP: 0018:ffffc90003af7a78 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff8880b853b280 RCX: 0000000000000001
RDX: 0000000000000046 RSI: ffffffff8de55850 RDI: ffffffff8c1af520
RBP: ffffc90003af7c20 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90d9b017 R11: 0000000000000129 R12: ffffffff90d9e3e4
R13: ffff8880b853c0c0 R14: ffff888037923d00 R15: ffff8880b853b280
 pick_next_task kernel/sched/core.c:6129 [inline]
 __schedule+0x1b7d/0x6120 kernel/sched/core.c:6849
 __schedule_loop kernel/sched/core.c:6990 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7005
 do_nanosleep+0x206/0x560 kernel/time/hrtimer.c:2124
 hrtimer_nanosleep+0x156/0x360 kernel/time/hrtimer.c:2171
 common_nsleep+0xa1/0xd0 kernel/time/posix-timers.c:1345
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1391 [inline]
 __se_sys_clock_nanosleep kernel/time/posix-timers.c:1368 [inline]
 __x64_sys_clock_nanosleep+0x336/0x480 kernel/time/posix-timers.c:1368
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe82f35cfce
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007ffeb20327b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 000055556a8e9500 RCX: 00007fe82f35cfce
RDX: 00007ffeb2032810 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffeb203287c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000001388
R13: 00000000000927c0 R14: 0000000000022e03 R15: 00007ffeb20328d0
 </TASK>
debug_locks && !(lock_is_held(&(__rq_lockp(rq))->dep_map) != 0)
WARNING: kernel/sched/sched.h:1600 at lockdep_assert_rq_held kernel/sched/sched.h:1600 [inline], CPU#0: syz-executor/5824
WARNING: kernel/sched/sched.h:1600 at lockdep_assert_rq_held kernel/sched/sched.h:1597 [inline], CPU#0: syz-executor/5824
WARNING: kernel/sched/sched.h:1600 at update_rq_clock+0x40a/0xd20 kernel/sched/core.c:850, CPU#0: syz-executor/5824
Modules linked in:
CPU: 0 UID: 0 PID: 5824 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:lockdep_assert_rq_held kernel/sched/sched.h:1600 [inline]
RIP: 0010:lockdep_assert_rq_held kernel/sched/sched.h:1597 [inline]
RIP: 0010:update_rq_clock+0x40a/0xd20 kernel/sched/core.c:850
Code: ab 48 0b 00 00 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f e9 18 9f ba 09 a8 04 0f 84 df fc ff ff 90 0f 0b 90 e9 d6 fc ff ff 90 <0f> 0b 90 e9 92 fc ff ff 4c 8d 83 40 0b 00 00 48 b8 00 00 00 00 00
RSP: 0018:ffffc90003af7a78 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff8880b853b280 RCX: 0000000000000001
RDX: 0000000000000046 RSI: ffffffff8de55850 RDI: ffffffff8c1af520
RBP: ffffc90003af7c20 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90d9b017 R11: 0000000000000129 R12: ffffffff90d9e3e4
R13: ffff8880b853c0c0 R14: ffff888037923d00 R15: ffff8880b853b280
FS:  000055556a8e9500(0000) GS:ffff88812434c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30c10ff8 CR3: 000000007511c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 pick_next_task kernel/sched/core.c:6129 [inline]
 __schedule+0x1b7d/0x6120 kernel/sched/core.c:6849
 __schedule_loop kernel/sched/core.c:6990 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7005
 do_nanosleep+0x206/0x560 kernel/time/hrtimer.c:2124
 hrtimer_nanosleep+0x156/0x360 kernel/time/hrtimer.c:2171
 common_nsleep+0xa1/0xd0 kernel/time/posix-timers.c:1345
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1391 [inline]
 __se_sys_clock_nanosleep kernel/time/posix-timers.c:1368 [inline]
 __x64_sys_clock_nanosleep+0x336/0x480 kernel/time/posix-timers.c:1368
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe82f35cfce
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007ffeb20327b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 000055556a8e9500 RCX: 00007fe82f35cfce
RDX: 00007ffeb2032810 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffeb203287c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000001388
R13: 00000000000927c0 R14: 0000000000022e03 R15: 00007ffeb20328d0
 </TASK>