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.3.4174/18164 is trying to acquire lock: ffffffff8cd23e80 (console_owner){-...}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:339 [inline] ffffffff8cd23e80 (console_owner){-...}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:232 [inline] ffffffff8cd23e80 (console_owner){-...}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:292 [inline] ffffffff8cd23e80 (console_owner){-...}-{0:0}, at: console_flush_all+0x10f/0xd00 kernel/printk/printk.c:2992 but task is already holding lock: ffff8880b8f3c458 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x32/0x50 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 raw_spin_rq_lock kernel/sched/sched.h:1372 [inline] rq_lock kernel/sched/sched.h:1681 [inline] task_fork_fair+0x62/0x1f0 kernel/sched/fair.c:12675 sched_cgroup_fork+0x333/0x3c0 kernel/sched/core.c:4816 copy_process+0x21e4/0x3d70 kernel/fork.c:2614 kernel_clone+0x21b/0x840 kernel/fork.c:2914 user_mode_thread+0xde/0x130 kernel/fork.c:2992 rest_init+0x27/0x300 init/main.c:697 arch_call_rest_init+0xe/0x10 init/main.c:829 start_kernel+0x459/0x4e0 init/main.c:1074 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555 copy_bootdata+0x0/0xe0 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x179/0x17b -> #4 (&p->pi_lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa8/0xf0 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:522 [inline] try_to_wake_up+0x60/0x1140 kernel/sched/core.c:4232 kick_pool+0x320/0x420 kernel/workqueue.c:1146 create_worker+0x5c0/0x7b0 kernel/workqueue.c:2218 workqueue_init+0x306/0x670 kernel/workqueue.c:6736 kernel_init_freeable+0x3a0/0x570 init/main.c:1538 kernel_init+0x1d/0x1c0 init/main.c:1443 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 -> #3 (&pool->lock){-.-.}-{2:2}: __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 __queue_work+0x69f/0x1020 kernel/workqueue.c:1764 queue_work_on+0x121/0x1e0 kernel/workqueue.c:1835 queue_work include/linux/workqueue.h:562 [inline] rpm_suspend+0x10bc/0x1a90 drivers/base/power/runtime.c:660 __pm_runtime_idle+0x12f/0x1a0 drivers/base/power/runtime.c:1102 pm_runtime_put include/linux/pm_runtime.h:450 [inline] __device_attach+0x33f/0x400 drivers/base/dd.c:1048 bus_probe_device+0x180/0x260 drivers/base/bus.c:534 device_add+0x85b/0xc20 drivers/base/core.c:3683 serial_base_port_add+0x2f2/0x420 drivers/tty/serial/serial_base_bus.c:178 serial_core_port_device_add drivers/tty/serial/serial_core.c:3382 [inline] serial_core_register_port+0x36d/0x2320 drivers/tty/serial/serial_core.c:3423 serial8250_register_8250_port+0x15ec/0x1f10 drivers/tty/serial/8250/8250_core.c:1142 serial_pnp_probe+0x549/0x730 drivers/tty/serial/8250/8250_pnp.c:478 pnp_device_probe+0x305/0x4b0 drivers/pnp/driver.c:111 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x25b/0xb40 drivers/base/dd.c:658 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __driver_attach+0x44e/0x6f0 drivers/base/dd.c:1216 bus_for_each_dev+0x22d/0x2a0 drivers/base/bus.c:370 bus_add_driver+0x340/0x640 drivers/base/bus.c:675 driver_register+0x23a/0x310 drivers/base/driver.c:246 serial8250_init+0x9a/0x170 drivers/tty/serial/8250/8250_core.c:1243 do_one_initcall+0x1fd/0x750 init/main.c:1238 do_initcall_level+0x137/0x1f0 init/main.c:1300 do_initcalls+0x69/0xd0 init/main.c:1316 kernel_init_freeable+0x3d2/0x570 init/main.c:1553 kernel_init+0x1d/0x1c0 init/main.c:1443 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 -> #2 (&dev->power.lock){-...}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa8/0xf0 kernel/locking/spinlock.c:162 __pm_runtime_resume+0x10f/0x170 drivers/base/power/runtime.c:1169 pm_runtime_get include/linux/pm_runtime.h:398 [inline] __uart_start+0x171/0x3e0 drivers/tty/serial/serial_core.c:148 uart_write+0x449/0x5d0 drivers/tty/serial/serial_core.c:633 process_output_block drivers/tty/n_tty.c:580 [inline] n_tty_write+0xd27/0x11d0 drivers/tty/n_tty.c:2395 iterate_tty_write drivers/tty/tty_io.c:1017 [inline] file_tty_write+0x54b/0x980 drivers/tty/tty_io.c:1088 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x43b/0x940 fs/read_write.c:584 ksys_write+0x147/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #1 (&port_lock_key){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa8/0xf0 kernel/locking/spinlock.c:162 serial8250_console_write+0x16d/0x17a0 drivers/tty/serial/8250/8250_port.c:3433 console_emit_next_record kernel/printk/printk.c:2944 [inline] console_flush_all+0x6cd/0xd00 kernel/printk/printk.c:3000 console_unlock+0xae/0x340 kernel/printk/printk.c:3069 vprintk_emit+0x477/0x600 kernel/printk/printk.c:2341 _printk+0xd0/0x110 kernel/printk/printk.c:2366 register_console+0x91b/0xe60 kernel/printk/printk.c:3583 univ8250_console_init+0x45/0x50 drivers/tty/serial/8250/8250_core.c:717 console_init+0x17b/0x5e0 kernel/printk/printk.c:3726 start_kernel+0x2c0/0x4e0 init/main.c:1010 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555 copy_bootdata+0x0/0xe0 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x179/0x17b -> #0 (console_owner){-...}-{0:0}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 console_lock_spinning_enable kernel/printk/printk.c:1871 [inline] console_emit_next_record kernel/printk/printk.c:2938 [inline] console_flush_all+0x693/0xd00 kernel/printk/printk.c:3000 console_unlock+0xae/0x340 kernel/printk/printk.c:3069 vprintk_emit+0x477/0x600 kernel/printk/printk.c:2341 _printk+0xd0/0x110 kernel/printk/printk.c:2366 fail_dump lib/fault-inject.c:45 [inline] should_fail_ex+0x37e/0x4d0 lib/fault-inject.c:153 strncpy_from_user+0x36/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x71/0x140 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:212 [inline] ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:307 [inline] bpf_probe_read_compat_str+0xe1/0x170 kernel/trace/bpf_trace.c:303 bpf_prog_c1796171ffc7efef+0x3d/0x3f bpf_dispatcher_nop_func include/linux/bpf.h:1223 [inline] __bpf_prog_run include/linux/filter.h:612 [inline] bpf_prog_run include/linux/filter.h:619 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2322 [inline] bpf_trace_run4+0x1f9/0x420 kernel/trace/bpf_trace.c:2363 __bpf_trace_sched_switch+0x17b/0x1e0 include/trace/events/sched.h:222 __traceiter_sched_switch+0x93/0xc0 include/trace/events/sched.h:222 trace_sched_switch include/trace/events/sched.h:222 [inline] __schedule+0x2197/0x44d0 kernel/sched/core.c:6696 schedule+0xbd/0x170 kernel/sched/core.c:6773 exp_funnel_lock kernel/rcu/tree_exp.h:315 [inline] synchronize_rcu_expedited+0x720/0x830 kernel/rcu/tree_exp.h:1004 synchronize_rcu+0x136/0x380 kernel/rcu/tree.c:3627 tp_rcu_cond_sync kernel/tracepoint.c:63 [inline] tracepoint_add_func+0x5e0/0x9a0 kernel/tracepoint.c:356 tracepoint_probe_register_prio kernel/tracepoint.c:511 [inline] tracepoint_probe_register+0x5e/0x90 kernel/tracepoint.c:531 perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline] perf_trace_event_init+0x4d2/0x9b0 kernel/trace/trace_event_perf.c:202 perf_trace_init+0x238/0x2d0 kernel/trace/trace_event_perf.c:226 perf_tp_event_init+0x8d/0x110 kernel/events/core.c:10203 perf_try_init_event+0x12b/0x3c0 kernel/events/core.c:11817 perf_init_event kernel/events/core.c:11887 [inline] perf_event_alloc+0xfa4/0x21b0 kernel/events/core.c:12168 __do_sys_perf_event_open kernel/events/core.c:12675 [inline] __se_sys_perf_event_open+0x70e/0x1c20 kernel/events/core.c:12566 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 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.3.4174/18164: #0: ffffffff96efbbf0 (&pmus_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:116 [inline] #0: ffffffff96efbbf0 (&pmus_srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:215 [inline] #0: ffffffff96efbbf0 (&pmus_srcu){.+.+}-{0:0}, at: perf_init_event kernel/events/core.c:11847 [inline] #0: ffffffff96efbbf0 (&pmus_srcu){.+.+}-{0:0}, at: perf_event_alloc+0xc06/0x21b0 kernel/events/core.c:12168 #1: ffffffff8cd85fa8 (event_mutex){+.+.}-{3:3}, at: perf_trace_init+0x50/0x2d0 kernel/trace/trace_event_perf.c:221 #2: ffffffff8cd78748 (tracepoints_mutex){+.+.}-{3:3}, at: tracepoint_probe_register_prio kernel/tracepoint.c:507 [inline] #2: ffffffff8cd78748 (tracepoints_mutex){+.+.}-{3:3}, at: tracepoint_probe_register+0x40/0x90 kernel/tracepoint.c:531 #3: ffff8880b8f3c458 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 #4: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #4: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #4: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2321 [inline] #4: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0xfd/0x420 kernel/trace/bpf_trace.c:2363 #5: ffffffff8cd23f60 (console_lock){+.+.}-{0:0}, at: _printk+0xd0/0x110 kernel/printk/printk.c:2366 #6: ffffffff8cc0b770 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:339 [inline] #6: ffffffff8cc0b770 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:232 [inline] #6: ffffffff8cc0b770 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:292 [inline] #6: ffffffff8cc0b770 (console_srcu){....}-{0:0}, at: console_flush_all+0x10f/0xd00 kernel/printk/printk.c:2992 stack backtrace: CPU: 1 PID: 18164 Comm: syz.3.4174 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 check_noncircular+0x2bd/0x3c0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 console_lock_spinning_enable kernel/printk/printk.c:1871 [inline] console_emit_next_record kernel/printk/printk.c:2938 [inline] console_flush_all+0x693/0xd00 kernel/printk/printk.c:3000 console_unlock+0xae/0x340 kernel/printk/printk.c:3069 vprintk_emit+0x477/0x600 kernel/printk/printk.c:2341 _printk+0xd0/0x110 kernel/printk/printk.c:2366 fail_dump lib/fault-inject.c:45 [inline] should_fail_ex+0x37e/0x4d0 lib/fault-inject.c:153 strncpy_from_user+0x36/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x71/0x140 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:212 [inline] ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:307 [inline] bpf_probe_read_compat_str+0xe1/0x170 kernel/trace/bpf_trace.c:303 bpf_prog_c1796171ffc7efef+0x3d/0x3f bpf_dispatcher_nop_func include/linux/bpf.h:1223 [inline] __bpf_prog_run include/linux/filter.h:612 [inline] bpf_prog_run include/linux/filter.h:619 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2322 [inline] bpf_trace_run4+0x1f9/0x420 kernel/trace/bpf_trace.c:2363 __bpf_trace_sched_switch+0x17b/0x1e0 include/trace/events/sched.h:222 __traceiter_sched_switch+0x93/0xc0 include/trace/events/sched.h:222 trace_sched_switch include/trace/events/sched.h:222 [inline] __schedule+0x2197/0x44d0 kernel/sched/core.c:6696 schedule+0xbd/0x170 kernel/sched/core.c:6773 exp_funnel_lock kernel/rcu/tree_exp.h:315 [inline] synchronize_rcu_expedited+0x720/0x830 kernel/rcu/tree_exp.h:1004 synchronize_rcu+0x136/0x380 kernel/rcu/tree.c:3627 tp_rcu_cond_sync kernel/tracepoint.c:63 [inline] tracepoint_add_func+0x5e0/0x9a0 kernel/tracepoint.c:356 tracepoint_probe_register_prio kernel/tracepoint.c:511 [inline] tracepoint_probe_register+0x5e/0x90 kernel/tracepoint.c:531 perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline] perf_trace_event_init+0x4d2/0x9b0 kernel/trace/trace_event_perf.c:202 perf_trace_init+0x238/0x2d0 kernel/trace/trace_event_perf.c:226 perf_tp_event_init+0x8d/0x110 kernel/events/core.c:10203 perf_try_init_event+0x12b/0x3c0 kernel/events/core.c:11817 perf_init_event kernel/events/core.c:11887 [inline] perf_event_alloc+0xfa4/0x21b0 kernel/events/core.c:12168 __do_sys_perf_event_open kernel/events/core.c:12675 [inline] __se_sys_perf_event_open+0x70e/0x1c20 kernel/events/core.c:12566 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fa11758eba9 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa1184c5038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007fa1177d5fa0 RCX: 00007fa11758eba9 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000200000000040 RBP: 00007fa1184c5090 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000001 R13: 00007fa1177d6038 R14: 00007fa1177d5fa0 R15: 00007ffde6f96208 CPU: 1 PID: 18164 Comm: syz.3.4174 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 fail_dump lib/fault-inject.c:52 [inline] should_fail_ex+0x39d/0x4d0 lib/fault-inject.c:153 strncpy_from_user+0x36/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x71/0x140 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:212 [inline] ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:307 [inline] bpf_probe_read_compat_str+0xe1/0x170 kernel/trace/bpf_trace.c:303 bpf_prog_c1796171ffc7efef+0x3d/0x3f bpf_dispatcher_nop_func include/linux/bpf.h:1223 [inline] __bpf_prog_run include/linux/filter.h:612 [inline] bpf_prog_run include/linux/filter.h:619 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2322 [inline] bpf_trace_run4+0x1f9/0x420 kernel/trace/bpf_trace.c:2363 __bpf_trace_sched_switch+0x17b/0x1e0 include/trace/events/sched.h:222 __traceiter_sched_switch+0x93/0xc0 include/trace/events/sched.h:222 trace_sched_switch include/trace/events/sched.h:222 [inline] __schedule+0x2197/0x44d0 kernel/sched/core.c:6696 schedule+0xbd/0x170 kernel/sched/core.c:6773 exp_funnel_lock kernel/rcu/tree_exp.h:315 [inline] synchronize_rcu_expedited+0x720/0x830 kernel/rcu/tree_exp.h:1004 synchronize_rcu+0x136/0x380 kernel/rcu/tree.c:3627 tp_rcu_cond_sync kernel/tracepoint.c:63 [inline] tracepoint_add_func+0x5e0/0x9a0 kernel/tracepoint.c:356 tracepoint_probe_register_prio kernel/tracepoint.c:511 [inline] tracepoint_probe_register+0x5e/0x90 kernel/tracepoint.c:531 perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline] perf_trace_event_init+0x4d2/0x9b0 kernel/trace/trace_event_perf.c:202 perf_trace_init+0x238/0x2d0 kernel/trace/trace_event_perf.c:226 perf_tp_event_init+0x8d/0x110 kernel/events/core.c:10203 perf_try_init_event+0x12b/0x3c0 kernel/events/core.c:11817 perf_init_event kernel/events/core.c:11887 [inline] perf_event_alloc+0xfa4/0x21b0 kernel/events/core.c:12168 __do_sys_perf_event_open kernel/events/core.c:12675 [inline] __se_sys_perf_event_open+0x70e/0x1c20 kernel/events/core.c:12566 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fa11758eba9 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa1184c5038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007fa1177d5fa0 RCX: 00007fa11758eba9 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000200000000040 RBP: 00007fa1184c5090 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000001 R13: 00007fa1177d6038 R14: 00007fa1177d5fa0 R15: 00007ffde6f96208