====================================================== WARNING: possible circular locking dependency detected 5.18.0-rc3-syzkaller-00080-gd569e86915b7 #0 Not tainted ------------------------------------------------------ syz-executor.0/17341 is trying to acquire lock: ffffffff8bc90400 (console_owner){-...}-{0:0}, at: console_trylock_spinning kernel/printk/printk.c:1874 [inline] ffffffff8bc90400 (console_owner){-...}-{0:0}, at: vprintk_emit+0x316/0x5f0 kernel/printk/printk.c:2271 but task is already holding lock: ffff88807ec49158 (&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:306 tty_port_default_wakeup+0x11/0x40 drivers/tty/tty_port.c:48 serial8250_tx_chars+0x4f3/0xa50 drivers/tty/serial/8250/8250_port.c:1866 serial8250_handle_irq.part.0+0x328/0x3d0 drivers/tty/serial/8250/8250_port.c:1953 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1926 [inline] serial8250_default_handle_irq+0xb2/0x220 drivers/tty/serial/8250/8250_port.c:1970 serial8250_interrupt+0xfd/0x200 drivers/tty/serial/8250/8250_core.c:126 __handle_irq_event_percpu+0x22b/0x880 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+0x25f/0xd00 kernel/irq/chip.c:817 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:636 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] acpi_safe_halt drivers/acpi/processor_idle.c:115 [inline] acpi_idle_do_entry+0x1c6/0x250 drivers/acpi/processor_idle.c:556 acpi_idle_enter+0x361/0x500 drivers/acpi/processor_idle.c:691 cpuidle_enter_state+0x1b1/0xc80 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:351 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x3e8/0x590 kernel/sched/idle.c:303 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:400 start_kernel+0x47f/0x4a0 init/main.c:1140 secondary_startup_64_no_verify+0xc3/0xcb -> #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+0x91a/0xb70 drivers/tty/serial/8250/8250_port.c:3358 call_console_drivers kernel/printk/printk.c:1952 [inline] console_unlock+0x9bc/0xdd0 kernel/printk/printk.c:2774 vprintk_emit+0x1b4/0x5f0 kernel/printk/printk.c:2272 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50 _printk+0xba/0xed kernel/printk/printk.c:2293 register_console kernel/printk/printk.c:3131 [inline] register_console+0x410/0x7c0 kernel/printk/printk.c:3012 univ8250_console_init+0x3a/0x46 drivers/tty/serial/8250/8250_core.c:679 console_init+0x3c1/0x58d kernel/printk/printk.c:3231 start_kernel+0x30b/0x4a0 init/main.c:1068 secondary_startup_64_no_verify+0xc3/0xcb -> #0 (console_owner){-...}-{0:0}: check_prev_add kernel/locking/lockdep.c:3065 [inline] check_prevs_add kernel/locking/lockdep.c:3188 [inline] validate_chain kernel/locking/lockdep.c:3803 [inline] __lock_acquire+0x2ac6/0x56c0 kernel/locking/lockdep.c:5029 lock_acquire kernel/locking/lockdep.c:5641 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606 console_trylock_spinning kernel/printk/printk.c:1895 [inline] vprintk_emit+0x353/0x5f0 kernel/printk/printk.c:2271 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50 _printk+0xba/0xed kernel/printk/printk.c:2293 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:1313 slab_pre_alloc_hook mm/slab.h:724 [inline] slab_alloc_node mm/slub.c:3131 [inline] slab_alloc mm/slub.c:3225 [inline] __kmalloc+0x7e/0x350 mm/slub.c:4410 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+0x8c/0x240 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 tty_send_xchar+0x251/0x370 drivers/tty/tty_io.c:1168 n_tty_ioctl_helper+0x179/0x2d0 drivers/tty/tty_ioctl.c:890 n_tty_ioctl+0x4b/0x360 drivers/tty/n_tty.c:2381 tty_ioctl+0xc57/0x15e0 drivers/tty/tty_io.c:2787 tty_compat_ioctl+0x2c4/0x3f0 drivers/tty/tty_io.c:2944 __do_compat_sys_ioctl+0x1c7/0x290 fs/ioctl.c:968 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c 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 *** 4 locks held by syz-executor.0/17341: #0: ffff888053fed098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffff888053fed130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock drivers/tty/tty_io.c:950 [inline] #1: ffff888053fed130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_send_xchar+0x1a1/0x370 drivers/tty/tty_io.c:1162 #2: ffff888053fed2e8 (&tty->termios_rwsem){++++}-{3:3}, at: tty_send_xchar+0x1ea/0x370 drivers/tty/tty_io.c:1165 #3: ffff88807ec49158 (&port->lock){-.-.}-{2:2}, at: pty_write+0xea/0x1e0 drivers/tty/pty.c:120 stack backtrace: CPU: 1 PID: 17341 Comm: syz-executor.0 Not tainted 5.18.0-rc3-syzkaller-00080-gd569e86915b7 #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 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2145 check_prev_add kernel/locking/lockdep.c:3065 [inline] check_prevs_add kernel/locking/lockdep.c:3188 [inline] validate_chain kernel/locking/lockdep.c:3803 [inline] __lock_acquire+0x2ac6/0x56c0 kernel/locking/lockdep.c:5029 lock_acquire kernel/locking/lockdep.c:5641 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606 console_trylock_spinning kernel/printk/printk.c:1895 [inline] vprintk_emit+0x353/0x5f0 kernel/printk/printk.c:2271 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50 _printk+0xba/0xed kernel/printk/printk.c:2293 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:1313 slab_pre_alloc_hook mm/slab.h:724 [inline] slab_alloc_node mm/slub.c:3131 [inline] slab_alloc mm/slub.c:3225 [inline] __kmalloc+0x7e/0x350 mm/slub.c:4410 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+0x8c/0x240 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 tty_send_xchar+0x251/0x370 drivers/tty/tty_io.c:1168 n_tty_ioctl_helper+0x179/0x2d0 drivers/tty/tty_ioctl.c:890 n_tty_ioctl+0x4b/0x360 drivers/tty/n_tty.c:2381 tty_ioctl+0xc57/0x15e0 drivers/tty/tty_io.c:2787 tty_compat_ioctl+0x2c4/0x3f0 drivers/tty/tty_io.c:2944 __do_compat_sys_ioctl+0x1c7/0x290 fs/ioctl.c:968 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f64549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7f5f5cc EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000000540a RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 CPU: 1 PID: 17341 Comm: syz-executor.0 Not tainted 5.18.0-rc3-syzkaller-00080-gd569e86915b7 #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 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:1313 slab_pre_alloc_hook mm/slab.h:724 [inline] slab_alloc_node mm/slub.c:3131 [inline] slab_alloc mm/slub.c:3225 [inline] __kmalloc+0x7e/0x350 mm/slub.c:4410 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+0x8c/0x240 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 tty_send_xchar+0x251/0x370 drivers/tty/tty_io.c:1168 n_tty_ioctl_helper+0x179/0x2d0 drivers/tty/tty_ioctl.c:890 n_tty_ioctl+0x4b/0x360 drivers/tty/n_tty.c:2381 tty_ioctl+0xc57/0x15e0 drivers/tty/tty_io.c:2787 tty_compat_ioctl+0x2c4/0x3f0 drivers/tty/tty_io.c:2944 __do_compat_sys_ioctl+0x1c7/0x290 fs/ioctl.c:968 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f64549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7f5f5cc EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000000540a RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: 03 74 c0 01 add 0x1(%rax,%rax,8),%esi 4: 10 05 03 74 b8 01 adc %al,0x1b87403(%rip) # 0x1b8740d a: 10 06 adc %al,(%rsi) c: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 10: 10 07 adc %al,(%rdi) 12: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi 16: 10 08 adc %cl,(%rax) 18: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1c: 00 00 add %al,(%rax) 1e: 00 00 add %al,(%rax) 20: 00 51 52 add %dl,0x52(%rcx) 23: 55 push %rbp 24: 89 e5 mov %esp,%ebp 26: 0f 34 sysenter 28: cd 80 int $0x80 * 2a: 5d pop %rbp <-- trapping instruction 2b: 5a pop %rdx 2c: 59 pop %rcx 2d: c3 retq 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 39: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi