FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
======================================================
WARNING: possible circular locking dependency detected
5.16.0-rc4-next-20211208 #1 Not tainted
------------------------------------------------------
syz-executor.2/10440 is trying to acquire lock:
ffffffff85114920 (console_owner){-.-.}-{0:0}, at: console_unlock+0x2f4/0xae0 kernel/printk/printk.c:2710

but task is already holding lock:
ffff888048721958 (&port->lock){-.-.}-{2:2}, at: pty_write+0xea/0x1e0 drivers/tty/pty.c:120

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:162
       tty_port_tty_get+0x1f/0x100 drivers/tty/tty_port.c:305
       tty_port_default_wakeup+0x11/0x40 drivers/tty/tty_port.c:48
       serial8250_tx_chars+0x50b/0xb00 drivers/tty/serial/8250/8250_port.c:1845
       serial8250_handle_irq.part.0+0x3f1/0x4c0 drivers/tty/serial/8250/8250_port.c:1932
       serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1905 [inline]
       serial8250_default_handle_irq+0xb8/0x230 drivers/tty/serial/8250/8250_port.c:1949
       serial8250_interrupt+0xf4/0x1a0 drivers/tty/serial/8250/8250_core.c:126
       __handle_irq_event_percpu+0x20f/0x820 kernel/irq/handle.c:158
       handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
       handle_irq_event+0xa7/0x1e0 kernel/irq/handle.c:210
       handle_edge_irq+0x262/0xd10 kernel/irq/chip.c:820
       generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
       handle_irq arch/x86/kernel/irq.c:231 [inline]
       __common_interrupt+0x92/0x1d0 arch/x86/kernel/irq.c:250
       common_interrupt+0x9f/0xc0 arch/x86/kernel/irq.c:240
       asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629
       native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
       arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
       default_idle+0xb/0x10 arch/x86/kernel/process.c:733
       default_idle_call+0x87/0xd0 kernel/sched/idle.c:112
       cpuidle_idle_call kernel/sched/idle.c:194 [inline]
       do_idle+0x3b9/0x530 kernel/sched/idle.c:306
       cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
       secondary_startup_64_no_verify+0xd5/0xdb

-> #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:162
       serial8250_console_write+0x90e/0xb20 drivers/tty/serial/8250/8250_port.c:3351
       call_console_drivers kernel/printk/printk.c:1932 [inline]
       console_unlock+0x756/0xae0 kernel/printk/printk.c:2714
       register_console kernel/printk/printk.c:3057 [inline]
       register_console+0x378/0x7d0 kernel/printk/printk.c:2948
       univ8250_console_init+0x3a/0x46 drivers/tty/serial/8250/8250_core.c:680
       console_init+0x3c9/0x599 kernel/printk/printk.c:3167
       start_kernel+0x301/0x4a5 init/main.c:1070
       secondary_startup_64_no_verify+0xd5/0xdb

-> #0 (console_owner){-.-.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3063 [inline]
       check_prevs_add kernel/locking/lockdep.c:3186 [inline]
       validate_chain kernel/locking/lockdep.c:3801 [inline]
       __lock_acquire+0x2a14/0x5b70 kernel/locking/lockdep.c:5027
       lock_acquire kernel/locking/lockdep.c:5639 [inline]
       lock_acquire+0x1a2/0x4d0 kernel/locking/lockdep.c:5604
       console_lock_spinning_enable kernel/printk/printk.c:1784 [inline]
       console_unlock+0x347/0xae0 kernel/printk/printk.c:2711
       vprintk_emit+0x198/0x450 kernel/printk/printk.c:2248
       vprintk+0x80/0x90 kernel/printk/printk_safe.c:50
       _printk+0xba/0xed kernel/printk/printk.c:2269
       fail_dump lib/fault-inject.c:45 [inline]
       should_fail+0x472/0x5a0 lib/fault-inject.c:146
       should_failslab+0x5/0x10 mm/slab_common.c:1304
       slab_pre_alloc_hook mm/slab.h:741 [inline]
       slab_alloc_node mm/slub.c:3145 [inline]
       slab_alloc mm/slub.c:3239 [inline]
       __kmalloc+0x72/0x330 mm/slub.c:4419
       kmalloc include/linux/slab.h:586 [inline]
       tty_buffer_alloc+0x23f/0x2a0 drivers/tty/tty_buffer.c:178
       __tty_buffer_request_room+0x156/0x2a0 drivers/tty/tty_buffer.c:274
       tty_insert_flip_string_fixed_flag+0x91/0x250 drivers/tty/tty_buffer.c:321
       tty_insert_flip_string include/linux/tty_flip.h:41 [inline]
       pty_write+0x11c/0x1e0 drivers/tty/pty.c:122
       n_tty_write+0xa86/0xfe0 drivers/tty/n_tty.c:2273
       do_tty_write drivers/tty/tty_io.c:1027 [inline]
       file_tty_write.constprop.0+0x529/0x910 drivers/tty/tty_io.c:1098
       call_write_iter include/linux/fs.h:2079 [inline]
       do_iter_readv_writev+0x479/0x750 fs/read_write.c:725
       do_iter_write+0x18d/0x700 fs/read_write.c:851
       vfs_writev+0x1aa/0x630 fs/read_write.c:924
       do_writev+0x139/0x300 fs/read_write.c:967
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

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 ***

6 locks held by syz-executor.2/10440:
 #0: ffff8880184ef098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffff8880184ef130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock drivers/tty/tty_io.c:950 [inline]
 #1: ffff8880184ef130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: do_tty_write drivers/tty/tty_io.c:973 [inline]
 #1: ffff8880184ef130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: file_tty_write.constprop.0+0x29f/0x910 drivers/tty/tty_io.c:1098
 #2: ffff8880184ef2e8 (&tty->termios_rwsem){++++}-{3:3}, at: n_tty_write+0x1bf/0xfe0 drivers/tty/n_tty.c:2233
 #3: ffffc9000846b378 (&ldata->output_lock){+.+.}-{3:3}, at: n_tty_write+0xa4d/0xfe0 drivers/tty/n_tty.c:2272
 #4: ffff888048721958 (&port->lock){-.-.}-{2:2}, at: pty_write+0xea/0x1e0 drivers/tty/pty.c:120
 #5: ffffffff851f4d60 (console_lock){+.+.}-{0:0}, at: vprintk+0x80/0x90 kernel/printk/printk_safe.c:50

stack backtrace:
CPU: 1 PID: 10440 Comm: syz-executor.2 Not tainted 5.16.0-rc4-next-20211208 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x8b/0xb3 lib/dump_stack.c:106
 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2143
 check_prev_add kernel/locking/lockdep.c:3063 [inline]
 check_prevs_add kernel/locking/lockdep.c:3186 [inline]
 validate_chain kernel/locking/lockdep.c:3801 [inline]
 __lock_acquire+0x2a14/0x5b70 kernel/locking/lockdep.c:5027
 lock_acquire kernel/locking/lockdep.c:5639 [inline]
 lock_acquire+0x1a2/0x4d0 kernel/locking/lockdep.c:5604
 console_lock_spinning_enable kernel/printk/printk.c:1784 [inline]
 console_unlock+0x347/0xae0 kernel/printk/printk.c:2711
 vprintk_emit+0x198/0x450 kernel/printk/printk.c:2248
 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50
 _printk+0xba/0xed kernel/printk/printk.c:2269
 fail_dump lib/fault-inject.c:45 [inline]
 should_fail+0x472/0x5a0 lib/fault-inject.c:146
 should_failslab+0x5/0x10 mm/slab_common.c:1304
 slab_pre_alloc_hook mm/slab.h:741 [inline]
 slab_alloc_node mm/slub.c:3145 [inline]
 slab_alloc mm/slub.c:3239 [inline]
 __kmalloc+0x72/0x330 mm/slub.c:4419
 kmalloc include/linux/slab.h:586 [inline]
 tty_buffer_alloc+0x23f/0x2a0 drivers/tty/tty_buffer.c:178
 __tty_buffer_request_room+0x156/0x2a0 drivers/tty/tty_buffer.c:274
 tty_insert_flip_string_fixed_flag+0x91/0x250 drivers/tty/tty_buffer.c:321
 tty_insert_flip_string include/linux/tty_flip.h:41 [inline]
 pty_write+0x11c/0x1e0 drivers/tty/pty.c:122
 n_tty_write+0xa86/0xfe0 drivers/tty/n_tty.c:2273
 do_tty_write drivers/tty/tty_io.c:1027 [inline]
 file_tty_write.constprop.0+0x529/0x910 drivers/tty/tty_io.c:1098
 call_write_iter include/linux/fs.h:2079 [inline]
 do_iter_readv_writev+0x479/0x750 fs/read_write.c:725
 do_iter_write+0x18d/0x700 fs/read_write.c:851
 vfs_writev+0x1aa/0x630 fs/read_write.c:924
 do_writev+0x139/0x300 fs/read_write.c:967
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f3d2d9e8b19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3d2af5e188 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f3d2dafbf60 RCX: 00007f3d2d9e8b19
RDX: 0000000000000001 RSI: 0000000020001400 RDI: 0000000000000003
RBP: 00007f3d2af5e1d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffc4a10355f R14: 00007f3d2af5e300 R15: 0000000000022000
 </TASK>
loop6: detected capacity change from 0 to 4
CPU: 1 PID: 10440 Comm: syz-executor.2 Not tainted 5.16.0-rc4-next-20211208 #1
EXT4-fs (loop6): Unrecognized mount option "n" or missing value
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x8b/0xb3 lib/dump_stack.c:106
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail.cold+0x5/0xa lib/fault-inject.c:146
 should_failslab+0x5/0x10 mm/slab_common.c:1304
 slab_pre_alloc_hook mm/slab.h:741 [inline]
 slab_alloc_node mm/slub.c:3145 [inline]
 slab_alloc mm/slub.c:3239 [inline]
 __kmalloc+0x72/0x330 mm/slub.c:4419
 kmalloc include/linux/slab.h:586 [inline]
 tty_buffer_alloc+0x23f/0x2a0 drivers/tty/tty_buffer.c:178
 __tty_buffer_request_room+0x156/0x2a0 drivers/tty/tty_buffer.c:274
 tty_insert_flip_string_fixed_flag+0x91/0x250 drivers/tty/tty_buffer.c:321
 tty_insert_flip_string include/linux/tty_flip.h:41 [inline]
 pty_write+0x11c/0x1e0 drivers/tty/pty.c:122
 n_tty_write+0xa86/0xfe0 drivers/tty/n_tty.c:2273
 do_tty_write drivers/tty/tty_io.c:1027 [inline]
 file_tty_write.constprop.0+0x529/0x910 drivers/tty/tty_io.c:1098
 call_write_iter include/linux/fs.h:2079 [inline]
 do_iter_readv_writev+0x479/0x750 fs/read_write.c:725
 do_iter_write+0x18d/0x700 fs/read_write.c:851
 vfs_writev+0x1aa/0x630 fs/read_write.c:924
 do_writev+0x139/0x300 fs/read_write.c:967
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f3d2d9e8b19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3d2af5e188 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f3d2dafbf60 RCX: 00007f3d2d9e8b19
RDX: 0000000000000001 RSI: 0000000020001400 RDI: 0000000000000003
RBP: 00007f3d2af5e1d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffc4a10355f R14: 00007f3d2af5e300 R15: 0000000000022000
 </TASK>
loop6: detected capacity change from 0 to 4
EXT4-fs (loop6): Unrecognized mount option "n" or missing value
loop3: detected capacity change from 0 to 512
EXT4-fs (loop3): Unrecognized mount option "Ð-òè" or missing value
loop3: detected capacity change from 0 to 512
EXT4-fs (loop3): Unrecognized mount option "Ð-òè" or missing value
loop4: detected capacity change from 0 to 184
isofs_fill_super: get root inode failed
Bluetooth: hci3: command 0x0405 tx timeout