======================================================
WARNING: possible circular locking dependency detected
5.7.0-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor095/20133 is trying to acquire lock:
ffffffff899b2d40 (console_owner){-.-.}-{0:0}, at: console_trylock_spinning kernel/printk/printk.c:1763 [inline]
ffffffff899b2d40 (console_owner){-.-.}-{0:0}, at: vprintk_emit+0x425/0x730 kernel/printk/printk.c:2031
but task is already holding lock:
ffffffff8d1db4b8 (&port->lock#2){-.-.}-{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){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x8c/0xbf 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+0x48f/0xa60 drivers/tty/serial/8250/8250_port.c:1828
serial8250_handle_irq.part.0+0x328/0x3d0 drivers/tty/serial/8250/8250_port.c:1915
serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1888 [inline]
serial8250_default_handle_irq+0xb5/0x140 drivers/tty/serial/8250/8250_port.c:1931
serial8250_interrupt+0xe6/0x190 drivers/tty/serial/8250/8250_core.c:126
__handle_irq_event_percpu+0x22e/0xa50 kernel/irq/handle.c:156
handle_irq_event_percpu+0x76/0x160 kernel/irq/handle.c:196
handle_irq_event+0xa2/0x12d kernel/irq/handle.c:213
handle_edge_irq+0x24b/0x8c0 kernel/irq/chip.c:830
generic_handle_irq_desc include/linux/irqdesc.h:156 [inline]
do_IRQ+0xd5/0x270 arch/x86/kernel/irq.c:250
ret_from_intr+0x0/0x2b
native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60
arch_safe_halt arch/x86/include/asm/paravirt.h:144 [inline]
default_idle+0x49/0x350 arch/x86/kernel/process.c:697
cpuidle_idle_call kernel/sched/idle.c:154 [inline]
do_idle+0x393/0x690 kernel/sched/idle.c:269
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:365
start_kernel+0x9be/0x9fb init/main.c:1041
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242
-> #1 (&port->lock){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x8c/0xbf kernel/locking/spinlock.c:159
serial8250_console_write+0x20d/0xb00 drivers/tty/serial/8250/8250_port.c:3240
call_console_drivers kernel/printk/printk.c:1827 [inline]
console_unlock+0xac7/0xf00 kernel/printk/printk.c:2515
vprintk_emit+0x2c4/0x730 kernel/printk/printk.c:2032
vprintk_func+0x8f/0x1a6 kernel/printk/printk_safe.c:386
printk+0xba/0xed kernel/printk/printk.c:2092
register_console kernel/printk/printk.c:2868 [inline]
register_console+0x55f/0x7e0 kernel/printk/printk.c:2747
univ8250_console_init+0x3a/0x46 drivers/tty/serial/8250/8250_core.c:690
console_init+0x43f/0x646 kernel/printk/printk.c:2968
start_kernel+0x76e/0x9fb init/main.c:969
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242
-> #0 (console_owner){-.-.}-{0:0}:
check_prev_add kernel/locking/lockdep.c:2496 [inline]
check_prevs_add kernel/locking/lockdep.c:2601 [inline]
validate_chain kernel/locking/lockdep.c:3218 [inline]
__lock_acquire+0x2a9a/0x48a0 kernel/locking/lockdep.c:4380
lock_acquire+0x1f2/0x8f0 kernel/locking/lockdep.c:4959
console_trylock_spinning kernel/printk/printk.c:1784 [inline]
vprintk_emit+0x462/0x730 kernel/printk/printk.c:2031
vprintk_func+0x8f/0x1a6 kernel/printk/printk_safe.c:386
printk+0xba/0xed kernel/printk/printk.c:2092
tty_port_close_start.part.0+0x4f7/0x550 drivers/tty/tty_port.c:569
tty_port_close_start drivers/tty/tty_port.c:641 [inline]
tty_port_close+0x46/0xf0 drivers/tty/tty_port.c:634
tty_release+0x3b9/0xe90 drivers/tty/tty_io.c:1679
__fput+0x33e/0x880 fs/file_table.c:281
task_work_run+0xf4/0x1b0 kernel/task_work.c:123
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0xb3f/0x2de0 kernel/exit.c:806
do_group_exit+0x125/0x340 kernel/exit.c:904
__do_sys_exit_group kernel/exit.c:915 [inline]
__se_sys_exit_group kernel/exit.c:913 [inline]
__x64_sys_exit_group+0x3a/0x50 kernel/exit.c:913
do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
entry_SYSCALL_64_after_hwframe+0x49/0xb3
other info that might help us debug this:
Chain exists of:
console_owner --> &port->lock --> &port->lock#2
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&port->lock#2);
lock(&port->lock);
lock(&port->lock#2);
lock(console_owner);
*** DEADLOCK ***
2 locks held by syz-executor095/20133:
#0: ffff888027d651c0 (&tty->legacy_mutex){+.+.}-{3:3}, at: tty_lock+0xbd/0x120 drivers/tty/tty_mutex.c:19
#1: ffffffff8d1db4b8 (&port->lock#2){-.-.}-{2:2}, at: tty_port_close_start.part.0+0x28/0x550 drivers/tty/tty_port.c:567
stack backtrace:
CPU: 3 PID: 20133 Comm: syz-executor095 Not tainted 5.7.0-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x188/0x20d lib/dump_stack.c:118
check_noncircular+0x32e/0x3e0 kernel/locking/lockdep.c:1827
check_prev_add kernel/locking/lockdep.c:2496 [inline]
check_prevs_add kernel/locking/lockdep.c:2601 [inline]
validate_chain kernel/locking/lockdep.c:3218 [inline]
__lock_acquire+0x2a9a/0x48a0 kernel/locking/lockdep.c:4380
lock_acquire+0x1f2/0x8f0 kernel/locking/lockdep.c:4959
console_trylock_spinning kernel/printk/printk.c:1784 [inline]
vprintk_emit+0x462/0x730 kernel/printk/printk.c:2031
vprintk_func+0x8f/0x1a6 kernel/printk/printk_safe.c:386
printk+0xba/0xed kernel/printk/printk.c:2092
tty_port_close_start.part.0+0x4f7/0x550 drivers/tty/tty_port.c:569
tty_port_close_start drivers/tty/tty_port.c:641 [inline]
tty_port_close+0x46/0xf0 drivers/tty/tty_port.c:634
tty_release+0x3b9/0xe90 drivers/tty/tty_io.c:1679
__fput+0x33e/0x880 fs/file_table.c:281
task_work_run+0xf4/0x1b0 kernel/task_work.c:123
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0xb3f/0x2de0 kernel/exit.c:806
do_group_exit+0x125/0x340 kernel/exit.c:904
__do_sys_exit_group kernel/exit.c:915 [inline]
__se_sys_exit_group kernel/exit.c:913 [inline]
__x64_sys_exit_group+0x3a/0x50 kernel/exit.c:913
do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x438738
Code: Bad RIP value.
RSP: 002b:00007ffc5e72aec8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000438738
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004b3cd0 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 00007ffc5e72af40 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006c7320 R14: 00007ffc5e72af38 R15: 20c49ba5e353f7cf