============================================
WARNING: possible recursive locking detected
5.15.0-syzkaller #0 Not tainted
--------------------------------------------
vivid-005-sdr-c/20619 is trying to acquire lock:
ffffffff90557310 (&port_lock_key){-.-.}-{2:2}, at: uart_write+0x12c/0x570 drivers/tty/serial/serial_core.c:577
but task is already holding lock:
ffffffff90557310 (&port_lock_key){-.-.}-{2:2}, at: serial8250_handle_irq.part.0+0x21/0x3d0 drivers/tty/serial/8250/8250_port.c:1908
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&port_lock_key);
lock(&port_lock_key);
*** DEADLOCK ***
May be due to missing lock nesting notation
3 locks held by vivid-005-sdr-c/20619:
#0: ffff88823bca2fd0 (&i->lock){-.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline]
#0: ffff88823bca2fd0 (&i->lock){-.-.}-{2:2}, at: serial8250_interrupt+0x3a/0x200 drivers/tty/serial/8250/8250_core.c:116
#1: ffffffff90557310 (&port_lock_key){-.-.}-{2:2}, at: serial8250_handle_irq.part.0+0x21/0x3d0 drivers/tty/serial/8250/8250_port.c:1908
#2: ffff888082c4a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1d/0x80 drivers/tty/tty_ldisc.c:273
stack backtrace:
CPU: 0 PID: 20619 Comm: vivid-005-sdr-c Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_deadlock_bug kernel/locking/lockdep.c:2944 [inline]
check_deadlock kernel/locking/lockdep.c:2987 [inline]
validate_chain kernel/locking/lockdep.c:3776 [inline]
__lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5015
lock_acquire kernel/locking/lockdep.c:5625 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162
uart_write+0x12c/0x570 drivers/tty/serial/serial_core.c:577
n_hdlc_send_frames+0x24b/0x490 drivers/tty/n_hdlc.c:290
tty_wakeup+0xe1/0x120 drivers/tty/tty_io.c:534
tty_port_default_wakeup+0x26/0x40 drivers/tty/tty_port.c:51
serial8250_tx_chars+0x4f3/0xad0 drivers/tty/serial/8250/8250_port.c:1845
serial8250_handle_irq.part.0+0x328/0x3d0 drivers/tty/serial/8250/8250_port.c:1932
serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1905 [inline]
serial8250_default_handle_irq+0xb2/0x220 drivers/tty/serial/8250/8250_port.c:1949
serial8250_interrupt+0xfd/0x200 drivers/tty/serial/8250/8250_core.c:126
__handle_irq_event_percpu+0x303/0x8f0 kernel/irq/handle.c:158
handle_irq_event_percpu kernel/irq/handle.c:198 [inline]
handle_irq_event+0x102/0x280 kernel/irq/handle.c:215
handle_edge_irq+0x25f/0xd00 kernel/irq/chip.c:822
generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
handle_irq arch/x86/kernel/irq.c:231 [inline]
__common_interrupt+0x9d/0x210 arch/x86/kernel/irq.c:250
common_interrupt+0xa4/0xc0 arch/x86/kernel/irq.c:240
asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629
RIP: 0010:lock_is_held_type+0xff/0x140 kernel/locking/lockdep.c:5673
Code: 00 00 b8 ff ff ff ff 65 0f c1 05 dc 94 c9 76 83 f8 01 75 29 9c 58 f6 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 <44> 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 45 31 ed eb b9 0f 0b 48
RSP: 0018:ffffc900055f7cf8 EFLAGS: 00000282
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffffff8b9838a0 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff862a3f11 R11: 0000000000000000 R12: ffff88801c940000
R13: 0000000000000000 R14: 00000000ffffffff R15: ffff888148880000
lock_is_held include/linux/lockdep.h:283 [inline]
schedule_debug kernel/sched/core.c:5542 [inline]
__schedule+0x1d0/0x4940 kernel/sched/core.c:6141
schedule+0xd2/0x260 kernel/sched/core.c:6323
vivid_thread_sdr_cap+0x934/0xdc0 drivers/media/test-drivers/vivid/vivid-sdr-cap.c:206
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
----------------
Code disassembly (best guess):
0: 00 00 add %al,(%rax)
2: b8 ff ff ff ff mov $0xffffffff,%eax
7: 65 0f c1 05 dc 94 c9 xadd %eax,%gs:0x76c994dc(%rip) # 0x76c994eb
e: 76
f: 83 f8 01 cmp $0x1,%eax
12: 75 29 jne 0x3d
14: 9c pushfq
15: 58 pop %rax
16: f6 c4 02 test $0x2,%ah
19: 75 3d jne 0x58
1b: 48 f7 04 24 00 02 00 testq $0x200,(%rsp)
22: 00
23: 74 01 je 0x26
25: fb sti
26: 48 83 c4 08 add $0x8,%rsp
* 2a: 44 89 e8 mov %r13d,%eax <-- trapping instruction
2d: 5b pop %rbx
2e: 5d pop %rbp
2f: 41 5c pop %r12
31: 41 5d pop %r13
33: 41 5e pop %r14
35: 41 5f pop %r15
37: c3 retq
38: 45 31 ed xor %r13d,%r13d
3b: eb b9 jmp 0xfffffff6
3d: 0f 0b ud2
3f: 48 rex.W