FAULT_INJECTION: forcing a failure. name fail_usercopy, interval 1, probability 0, space 0, times 0 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.8.7117/25997 is trying to acquire lock: ffffffff8cb1f460 (console_owner){-...}-{0:0}, at: console_lock_spinning_enable kernel/printk/printk.c:1818 [inline] ffffffff8cb1f460 (console_owner){-...}-{0:0}, at: console_emit_next_record+0x683/0xba0 kernel/printk/printk.c:2774 but task is already holding lock: ffff8880b8e3ab18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:538 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x2e/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:538 raw_spin_rq_lock kernel/sched/sched.h:1362 [inline] rq_lock kernel/sched/sched.h:1652 [inline] task_fork_fair+0x5c/0x350 kernel/sched/fair.c:11928 sched_cgroup_fork+0x32c/0x3c0 kernel/sched/core.c:4686 copy_process+0x24de/0x4030 kernel/fork.c:2464 kernel_clone+0x24b/0x900 kernel/fork.c:2762 user_mode_thread+0x10d/0x180 kernel/fork.c:2838 rest_init+0x23/0x300 init/main.c:710 start_kernel+0x0/0x53c init/main.c:905 start_kernel+0x493/0x53c init/main.c:1152 secondary_startup_64_no_verify+0xcf/0xdb -> #3 (&p->pi_lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162 try_to_wake_up+0x5c/0x1080 kernel/sched/core.c:4112 __wake_up_common+0x2a4/0x4e0 kernel/sched/wait.c:107 __wake_up_common_lock kernel/sched/wait.c:138 [inline] __wake_up+0x121/0x1a0 kernel/sched/wait.c:160 tty_port_default_wakeup+0x9e/0xf0 drivers/tty/tty_port.c:71 serial8250_tx_chars+0x629/0x830 drivers/tty/serial/8250/8250_port.c:1854 serial8250_handle_irq+0x516/0x6d0 drivers/tty/serial/8250/8250_port.c:1961 serial8250_default_handle_irq+0xb4/0x1a0 drivers/tty/serial/8250/8250_port.c:1981 serial8250_interrupt+0x9b/0x1c0 drivers/tty/serial/8250/8250_core.c:126 __handle_irq_event_percpu+0x293/0xa50 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0x87/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x243/0xb20 kernel/irq/chip.c:819 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq arch/x86/kernel/irq.c:233 [inline] __common_interrupt+0xd7/0x1e0 arch/x86/kernel/irq.c:252 common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:242 asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:682 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:741 default_idle_call+0x84/0xc0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x20d/0x5a0 kernel/sched/idle.c:303 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401 rest_init+0x2dc/0x300 init/main.c:745 start_kernel+0x0/0x53c init/main.c:905 start_kernel+0x493/0x53c init/main.c:1152 secondary_startup_64_no_verify+0xcf/0xdb -> #2 (&tty->write_wait){-...}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162 __wake_up_common_lock kernel/sched/wait.c:137 [inline] __wake_up+0x107/0x1a0 kernel/sched/wait.c:160 tty_port_default_wakeup+0x9e/0xf0 drivers/tty/tty_port.c:71 serial8250_tx_chars+0x629/0x830 drivers/tty/serial/8250/8250_port.c:1854 serial8250_handle_irq+0x516/0x6d0 drivers/tty/serial/8250/8250_port.c:1961 serial8250_default_handle_irq+0xb4/0x1a0 drivers/tty/serial/8250/8250_port.c:1981 serial8250_interrupt+0x9b/0x1c0 drivers/tty/serial/8250/8250_core.c:126 __handle_irq_event_percpu+0x293/0xa50 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0x87/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x243/0xb20 kernel/irq/chip.c:819 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq arch/x86/kernel/irq.c:233 [inline] __common_interrupt+0xd7/0x1e0 arch/x86/kernel/irq.c:252 common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:242 asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:682 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:741 default_idle_call+0x84/0xc0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x20d/0x5a0 kernel/sched/idle.c:303 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401 rest_init+0x2dc/0x300 init/main.c:745 start_kernel+0x0/0x53c init/main.c:905 start_kernel+0x493/0x53c init/main.c:1152 secondary_startup_64_no_verify+0xcf/0xdb -> #1 (&port_lock_key){-...}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162 serial8250_console_write+0x171/0x17f0 drivers/tty/serial/8250/8250_port.c:3432 call_console_driver kernel/printk/printk.c:1977 [inline] console_emit_next_record+0x79e/0xba0 kernel/printk/printk.c:2777 console_flush_all kernel/printk/printk.c:-1 [inline] console_unlock+0x223/0x630 kernel/printk/printk.c:2906 vprintk_emit+0x4b3/0x6a0 kernel/printk/printk.c:2303 _printk+0xda/0x130 kernel/printk/printk.c:2328 register_console+0x6cf/0x9c0 kernel/printk/printk.c:3269 univ8250_console_init+0x41/0x43 drivers/tty/serial/8250/8250_core.c:687 console_init+0x1bc/0x78e kernel/printk/printk.c:3359 start_kernel+0x306/0x53c init/main.c:1088 secondary_startup_64_no_verify+0xcf/0xdb -> #0 (console_owner){-...}-{0:0}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 console_lock_spinning_enable kernel/printk/printk.c:1818 [inline] console_emit_next_record+0x6a4/0xba0 kernel/printk/printk.c:2774 console_flush_all kernel/printk/printk.c:-1 [inline] console_unlock+0x223/0x630 kernel/printk/printk.c:2906 vprintk_emit+0x4b3/0x6a0 kernel/printk/printk.c:2303 _printk+0xda/0x130 kernel/printk/printk.c:2328 fail_dump lib/fault-inject.c:45 [inline] should_fail_ex+0x37a/0x4d0 lib/fault-inject.c:147 strncpy_from_user+0x32/0x350 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x6d/0x140 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:213 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:210 bpf_prog_7acee76fef7300d9+0x5b/0x5f bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x1d5/0x3e0 kernel/trace/bpf_trace.c:2324 trace_tlb_flush+0x143/0x190 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x779/0xb40 arch/x86/mm/tlb.c:-1 context_switch kernel/sched/core.c:5230 [inline] __schedule+0xf3c/0x40e0 kernel/sched/core.c:6562 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6731 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6755 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 on_each_cpu_cond_mask+0x71/0x80 kernel/smp.c:1166 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1574 [inline] text_poke_bp_batch+0x2b7/0x850 arch/x86/kernel/alternative.c:1774 text_poke_flush arch/x86/kernel/alternative.c:1965 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x11f/0x240 kernel/jump_label.c:207 static_key_enable+0x16/0x20 kernel/jump_label.c:220 tracepoint_add_func+0x907/0x990 kernel/tracepoint.c:361 tracepoint_probe_register_prio_may_exist+0x5c/0x90 kernel/tracepoint.c:482 bpf_raw_tp_link_attach+0x3e9/0x570 kernel/bpf/syscall.c:3397 bpf_raw_tracepoint_open+0x194/0x200 kernel/bpf/syscall.c:3424 __sys_bpf+0x581/0x780 kernel/bpf/syscall.c:5072 __do_sys_bpf kernel/bpf/syscall.c:5134 [inline] __se_sys_bpf kernel/bpf/syscall.c:5132 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5132 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 other info that might help us debug this: Chain exists of: console_owner --> &p->pi_lock --> &rq->__lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&rq->__lock); lock(&p->pi_lock); lock(&rq->__lock); lock(console_owner); *** DEADLOCK *** 7 locks held by syz.8.7117/25997: #0: ffffffff8cb724c8 (tracepoints_mutex){+.+.}-{3:3}, at: tracepoint_probe_register_prio_may_exist+0x40/0x90 kernel/tracepoint.c:478 #1: ffffffff8c9c7b70 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_enable+0xe/0x20 kernel/jump_label.c:219 #2: ffffffff8cbc7348 (jump_label_mutex){+.+.}-{3:3}, at: jump_label_lock kernel/jump_label.c:27 [inline] #2: ffffffff8cbc7348 (jump_label_mutex){+.+.}-{3:3}, at: static_key_enable_cpuslocked+0xc2/0x240 kernel/jump_label.c:204 #3: ffffffff8c9dcf08 (text_mutex){+.+.}-{3:3}, at: arch_jump_label_transform_apply+0xe/0x20 arch/x86/kernel/jump_label.c:145 #4: ffff8880b8e3ab18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:538 #5: ffffffff8cb2b2a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #5: ffffffff8cb2b2a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #5: ffffffff8cb2b2a0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline] #5: ffffffff8cb2b2a0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xe2/0x3e0 kernel/trace/bpf_trace.c:2324 #6: ffffffff8cb1f540 (console_lock){+.+.}-{0:0}, at: _printk+0xda/0x130 kernel/printk/printk.c:2328 stack backtrace: CPU: 0 PID: 25997 Comm: syz.8.7117 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 console_lock_spinning_enable kernel/printk/printk.c:1818 [inline] console_emit_next_record+0x6a4/0xba0 kernel/printk/printk.c:2774 console_flush_all kernel/printk/printk.c:-1 [inline] console_unlock+0x223/0x630 kernel/printk/printk.c:2906 vprintk_emit+0x4b3/0x6a0 kernel/printk/printk.c:2303 _printk+0xda/0x130 kernel/printk/printk.c:2328 fail_dump lib/fault-inject.c:45 [inline] should_fail_ex+0x37a/0x4d0 lib/fault-inject.c:147 strncpy_from_user+0x32/0x350 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x6d/0x140 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:213 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:210 bpf_prog_7acee76fef7300d9+0x5b/0x5f bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x1d5/0x3e0 kernel/trace/bpf_trace.c:2324 trace_tlb_flush+0x143/0x190 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x779/0xb40 arch/x86/mm/tlb.c:-1 context_switch kernel/sched/core.c:5230 [inline] __schedule+0xf3c/0x40e0 kernel/sched/core.c:6562 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6731 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6755 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 on_each_cpu_cond_mask+0x71/0x80 kernel/smp.c:1166 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1574 [inline] text_poke_bp_batch+0x2b7/0x850 arch/x86/kernel/alternative.c:1774 text_poke_flush arch/x86/kernel/alternative.c:1965 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x11f/0x240 kernel/jump_label.c:207 static_key_enable+0x16/0x20 kernel/jump_label.c:220 tracepoint_add_func+0x907/0x990 kernel/tracepoint.c:361 tracepoint_probe_register_prio_may_exist+0x5c/0x90 kernel/tracepoint.c:482 bpf_raw_tp_link_attach+0x3e9/0x570 kernel/bpf/syscall.c:3397 bpf_raw_tracepoint_open+0x194/0x200 kernel/bpf/syscall.c:3424 __sys_bpf+0x581/0x780 kernel/bpf/syscall.c:5072 __do_sys_bpf kernel/bpf/syscall.c:5134 [inline] __se_sys_bpf kernel/bpf/syscall.c:5132 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5132 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f154c19acb9 Code: Unable to access opcode bytes at 0x7f154c19ac8f. RSP: 002b:00007f154d005028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f154c415fa0 RCX: 00007f154c19acb9 RDX: 0000000000000010 RSI: 0000200000000040 RDI: 0000000000000011 RBP: 00007f154d005090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f154c416038 R14: 00007f154c415fa0 R15: 00007ffc65fbb058 CPU: 0 PID: 25997 Comm: syz.8.7117 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 fail_dump lib/fault-inject.c:52 [inline] should_fail_ex+0x399/0x4d0 lib/fault-inject.c:147 strncpy_from_user+0x32/0x350 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x6d/0x140 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:213 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:210 bpf_prog_7acee76fef7300d9+0x5b/0x5f bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x1d5/0x3e0 kernel/trace/bpf_trace.c:2324 trace_tlb_flush+0x143/0x190 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x779/0xb40 arch/x86/mm/tlb.c:-1 context_switch kernel/sched/core.c:5230 [inline] __schedule+0xf3c/0x40e0 kernel/sched/core.c:6562 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6731 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6755 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 on_each_cpu_cond_mask+0x71/0x80 kernel/smp.c:1166 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1574 [inline] text_poke_bp_batch+0x2b7/0x850 arch/x86/kernel/alternative.c:1774 text_poke_flush arch/x86/kernel/alternative.c:1965 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x11f/0x240 kernel/jump_label.c:207 static_key_enable+0x16/0x20 kernel/jump_label.c:220 tracepoint_add_func+0x907/0x990 kernel/tracepoint.c:361 tracepoint_probe_register_prio_may_exist+0x5c/0x90 kernel/tracepoint.c:482 bpf_raw_tp_link_attach+0x3e9/0x570 kernel/bpf/syscall.c:3397 bpf_raw_tracepoint_open+0x194/0x200 kernel/bpf/syscall.c:3424 __sys_bpf+0x581/0x780 kernel/bpf/syscall.c:5072 __do_sys_bpf kernel/bpf/syscall.c:5134 [inline] __se_sys_bpf kernel/bpf/syscall.c:5132 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5132 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f154c19acb9 Code: Unable to access opcode bytes at 0x7f154c19ac8f. RSP: 002b:00007f154d005028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f154c415fa0 RCX: 00007f154c19acb9 RDX: 0000000000000010 RSI: 0000200000000040 RDI: 0000000000000011 RBP: 00007f154d005090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f154c416038 R14: 00007f154c415fa0 R15: 00007ffc65fbb058