======================================================
WARNING: possible circular locking dependency detected
5.11.0-rc6-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor823/12284 is trying to acquire lock:
ffffffff8bc82ce0 (console_owner){....}-{0:0}, at: console_unlock+0x2fb/0xbb0 kernel/printk/printk.c:2545
but task is already holding lock:
ffffffff906b3358 (&port->lock){-.-.}-{2:2}, at: tty_port_close_start.part.0+0x28/0x550 drivers/tty/tty_port.c:567
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&port->lock){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:159
tty_port_tty_get+0x1f/0x100 drivers/tty/tty_port.c:288
tty_port_default_wakeup+0x11/0x40 drivers/tty/tty_port.c:47
serial8250_tx_chars+0x487/0xa80 drivers/tty/serial/8250/8250_port.c:1832
serial8250_handle_irq.part.0+0x328/0x3d0 drivers/tty/serial/8250/8250_port.c:1919
serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1892 [inline]
serial8250_default_handle_irq+0xb2/0x220 drivers/tty/serial/8250/8250_port.c:1935
serial8250_interrupt+0xfd/0x200 drivers/tty/serial/8250/8250_core.c:126
__handle_irq_event_percpu+0x303/0x8f0 kernel/irq/handle.c:156
handle_irq_event_percpu kernel/irq/handle.c:196 [inline]
handle_irq_event+0x102/0x290 kernel/irq/handle.c:213
handle_edge_irq+0x25f/0xd00 kernel/irq/chip.c:819
asm_call_irq_on_stack+0xf/0x20
__run_irq_on_irqstack arch/x86/include/asm/irq_stack.h:48 [inline]
run_irq_on_irqstack_cond arch/x86/include/asm/irq_stack.h:101 [inline]
handle_irq arch/x86/kernel/irq.c:230 [inline]
__common_interrupt arch/x86/kernel/irq.c:249 [inline]
common_interrupt+0x120/0x200 arch/x86/kernel/irq.c:239
asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:620
native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline]
arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline]
default_idle+0xe/0x10 arch/x86/kernel/process.c:688
default_idle_call+0x87/0xd0 kernel/sched/idle.c:112
cpuidle_idle_call kernel/sched/idle.c:194 [inline]
do_idle+0x3fa/0x590 kernel/sched/idle.c:299
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:396
start_secondary+0x274/0x350 arch/x86/kernel/smpboot.c:272
secondary_startup_64_no_verify+0xb0/0xbb
-> #1 (&port_lock_key){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:159
serial8250_console_write+0x880/0xa90 drivers/tty/serial/8250/8250_port.c:3292
call_console_drivers kernel/printk/printk.c:1856 [inline]
console_unlock+0x841/0xbb0 kernel/printk/printk.c:2570
vprintk_emit+0x189/0x490 kernel/printk/printk.c:2092
vprintk_func+0x8d/0x1e0 kernel/printk/printk_safe.c:393
printk+0xba/0xed kernel/printk/printk.c:2140
register_console kernel/printk/printk.c:2921 [inline]
register_console+0x5d1/0x800 kernel/printk/printk.c:2801
univ8250_console_init+0x3a/0x46 drivers/tty/serial/8250/8250_core.c:690
console_init+0x3c7/0x596 kernel/printk/printk.c:3021
start_kernel+0x2fc/0x48c init/main.c:989
secondary_startup_64_no_verify+0xb0/0xbb
-> #0 (console_owner){....}-{0:0}:
check_prev_add kernel/locking/lockdep.c:2868 [inline]
check_prevs_add kernel/locking/lockdep.c:2993 [inline]
validate_chain kernel/locking/lockdep.c:3608 [inline]
__lock_acquire+0x2b26/0x54f0 kernel/locking/lockdep.c:4832
lock_acquire kernel/locking/lockdep.c:5442 [inline]
lock_acquire+0x1a8/0x720 kernel/locking/lockdep.c:5407
console_lock_spinning_enable kernel/printk/printk.c:1708 [inline]
console_unlock+0x37a/0xbb0 kernel/printk/printk.c:2567
vprintk_emit+0x189/0x490 kernel/printk/printk.c:2092
vprintk_func+0x8d/0x1e0 kernel/printk/printk_safe.c:393
printk+0xba/0xed kernel/printk/printk.c:2140
tty_port_close_start.part.0+0x503/0x550 drivers/tty/tty_port.c:569
tty_port_close_start drivers/tty/tty_port.c:641 [inline]
tty_port_close+0x46/0x170 drivers/tty/tty_port.c:634
tty_release+0x45e/0x1210 drivers/tty/tty_io.c:1694
__fput+0x283/0x920 fs/file_table.c:280
task_work_run+0xdd/0x190 kernel/task_work.c:140
exit_task_work include/linux/task_work.h:30 [inline]
do_exit+0xc5c/0x2ae0 kernel/exit.c:825
do_group_exit+0x125/0x310 kernel/exit.c:922
get_signal+0x427/0x20f0 kernel/signal.c:2773
arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811
handle_signal_work kernel/entry/common.c:147 [inline]
exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:201
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
entry_SYSCALL_64_after_hwframe+0x44/0xa9
other info that might help us debug this:
Chain exists of:
console_owner --> &port_lock_key --> &port->lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&port->lock);
lock(&port_lock_key);
lock(&port->lock);
lock(console_owner);
*** DEADLOCK ***
3 locks held by syz-executor823/12284:
#0: ffff8880162e41c0 (&tty->legacy_mutex){+.+.}-{3:3}, at: tty_lock+0xbd/0x120 drivers/tty/tty_mutex.c:19
#1: ffffffff906b3358 (&port->lock){-.-.}-{2:2}, at: tty_port_close_start.part.0+0x28/0x550 drivers/tty/tty_port.c:567
#2: ffffffff8bd63060 (console_lock){+.+.}-{0:0}, at: vprintk_func+0x8d/0x1e0 kernel/printk/printk_safe.c:393
stack backtrace:
CPU: 3 PID: 12284 Comm: syz-executor823 Not tainted 5.11.0-rc6-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x107/0x163 lib/dump_stack.c:120
check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2117
check_prev_add kernel/locking/lockdep.c:2868 [inline]
check_prevs_add kernel/locking/lockdep.c:2993 [inline]
validate_chain kernel/locking/lockdep.c:3608 [inline]
__lock_acquire+0x2b26/0x54f0 kernel/locking/lockdep.c:4832
lock_acquire kernel/locking/lockdep.c:5442 [inline]
lock_acquire+0x1a8/0x720 kernel/locking/lockdep.c:5407
console_lock_spinning_enable kernel/printk/printk.c:1708 [inline]
console_unlock+0x37a/0xbb0 kernel/printk/printk.c:2567
vprintk_emit+0x189/0x490 kernel/printk/printk.c:2092
vprintk_func+0x8d/0x1e0 kernel/printk/printk_safe.c:393
printk+0xba/0xed kernel/printk/printk.c:2140
tty_port_close_start.part.0+0x503/0x550 drivers/tty/tty_port.c:569
tty_port_close_start drivers/tty/tty_port.c:641 [inline]
tty_port_close+0x46/0x170 drivers/tty/tty_port.c:634
tty_release+0x45e/0x1210 drivers/tty/tty_io.c:1694
__fput+0x283/0x920 fs/file_table.c:280
task_work_run+0xdd/0x190 kernel/task_work.c:140
exit_task_work include/linux/task_work.h:30 [inline]
do_exit+0xc5c/0x2ae0 kernel/exit.c:825
do_group_exit+0x125/0x310 kernel/exit.c:922
get_signal+0x427/0x20f0 kernel/signal.c:2773
arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811
handle_signal_work kernel/entry/common.c:147 [inline]
exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:201
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x44d2e9
Code: Unable to access opcode bytes at RIP 0x44d2bf.
RSP: 002b:00007f5c895d1318 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00000000004ca3f8 RCX: 000000000044d2e9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000004ca3f8
RBP: 00000000004ca3f0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 7974742f7665642f
R13: 00007fff228b4faf R14: 00007f5c895d1400 R15: 0000000000022000