FAULT_INJECTION: forcing a failure. name fail_usercopy, interval 1, probability 0, space 0, times 0 ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc3-syzkaller #0 Not tainted ------------------------------------------------------ syz.0.116/6336 is trying to acquire lock: ffffffff8e4d1ee0 (console_owner){-...}-{0:0}, at: console_lock_spinning_enable+0x9f/0xd0 kernel/printk/printk.c:1924 but task is already holding lock: ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline] ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599 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+0x31/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:606 raw_spin_rq_lock kernel/sched/sched.h:1532 [inline] task_rq_lock+0xcf/0x490 kernel/sched/core.c:708 cgroup_move_task+0x81/0x2a0 kernel/sched/psi.c:1161 css_set_move_task+0x288/0x5f0 kernel/cgroup/cgroup.c:918 cgroup_post_fork+0x201/0x9e0 kernel/cgroup/cgroup.c:6754 copy_process+0x5cfc/0x76a0 kernel/fork.c:2413 kernel_clone+0xfc/0x960 kernel/fork.c:2599 user_mode_thread+0xc7/0x110 kernel/fork.c:2677 rest_init+0x23/0x2b0 init/main.c:710 start_kernel+0x3ee/0x4d0 init/main.c:1102 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x148 -> #4 (&p->pi_lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline] try_to_wake_up+0xb2/0x1680 kernel/sched/core.c:4226 create_worker+0x339/0x7e0 kernel/workqueue.c:2834 workqueue_init+0x4e5/0xbd0 kernel/workqueue.c:7944 kernel_init_freeable+0x32f/0x900 init/main.c:1569 kernel_init+0x1c/0x2b0 init/main.c:1474 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #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+0x26b/0x10f0 kernel/workqueue.c:2301 queue_work_on+0x15f/0x1f0 kernel/workqueue.c:2392 queue_work include/linux/workqueue.h:662 [inline] rpm_suspend+0xeba/0x11d0 drivers/base/power/runtime.c:673 rpm_idle+0x5b4/0x730 drivers/base/power/runtime.c:547 __pm_runtime_idle+0xba/0x1a0 drivers/base/power/runtime.c:1112 pm_runtime_put include/linux/pm_runtime.h:470 [inline] __device_attach+0x37e/0x4b0 drivers/base/dd.c:1047 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1a70 drivers/base/core.c:3692 serial_base_port_add+0x357/0x4b0 drivers/tty/serial/serial_base_bus.c:179 serial_core_port_device_add drivers/tty/serial/serial_core.c:3341 [inline] serial_core_register_port+0x13c/0x2570 drivers/tty/serial/serial_core.c:3380 serial8250_register_8250_port+0x159b/0x23c0 drivers/tty/serial/8250/8250_core.c:822 serial_pnp_probe+0x431/0x910 drivers/tty/serial/8250/8250_pnp.c:480 pnp_device_probe+0x2a8/0x4d0 drivers/pnp/driver.c:111 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x241/0xa90 drivers/base/dd.c:657 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829 __driver_attach+0x283/0x580 drivers/base/dd.c:1215 bus_for_each_dev+0x13b/0x1d0 drivers/base/bus.c:370 bus_add_driver+0x2e9/0x690 drivers/base/bus.c:678 driver_register+0x15c/0x4b0 drivers/base/driver.c:249 serial8250_init+0xc9/0x1e0 drivers/tty/serial/8250/8250_platform.c:315 do_one_initcall+0x120/0x6e0 init/main.c:1274 do_initcall_level init/main.c:1336 [inline] do_initcalls init/main.c:1352 [inline] do_basic_setup init/main.c:1371 [inline] kernel_init_freeable+0x5c2/0x900 init/main.c:1584 kernel_init+0x1c/0x2b0 init/main.c:1474 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #2 (&dev->power.lock){-.-.}-{3:3}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 __pm_runtime_resume+0xa9/0x170 drivers/base/power/runtime.c:1179 pm_runtime_get include/linux/pm_runtime.h:418 [inline] __uart_start+0x1b0/0x4c0 drivers/tty/serial/serial_core.c:149 uart_write+0x218/0xb30 drivers/tty/serial/serial_core.c:636 process_output_block drivers/tty/n_tty.c:561 [inline] n_tty_write+0x40f/0x1160 drivers/tty/n_tty.c:2377 iterate_tty_write drivers/tty/tty_io.c:1006 [inline] file_tty_write.constprop.0+0x504/0x9b0 drivers/tty/tty_io.c:1081 tty_write drivers/tty/tty_io.c:1102 [inline] redirected_tty_write drivers/tty/tty_io.c:1125 [inline] redirected_tty_write+0xd4/0x150 drivers/tty/tty_io.c:1105 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x6c4/0x1150 fs/read_write.c:686 ksys_write+0x12a/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&port_lock_key){-.-.}-{3:3}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:717 [inline] serial8250_console_write+0x181/0x1890 drivers/tty/serial/8250/8250_port.c:3415 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x801/0xc60 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 _printk+0xc7/0x100 kernel/printk/printk.c:2475 register_console+0xc2d/0x11b0 kernel/printk/printk.c:4125 univ8250_console_init+0x5f/0x90 drivers/tty/serial/8250/8250_core.c:513 console_init+0x14f/0x680 kernel/printk/printk.c:4323 start_kernel+0x29f/0x4d0 init/main.c:1036 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x148 -> #0 (console_owner){-...}-{0:0}: check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain kernel/locking/lockdep.c:3911 [inline] __lock_acquire+0x126f/0x1c90 kernel/locking/lockdep.c:5240 lock_acquire kernel/locking/lockdep.c:5871 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828 console_lock_spinning_enable+0xb0/0xd0 kernel/printk/printk.c:1924 console_emit_next_record kernel/printk/printk.c:3132 [inline] console_flush_all+0x7aa/0xc60 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 _printk+0xc7/0x100 kernel/printk/printk.c:2475 fail_dump lib/fault-inject.c:66 [inline] should_fail_ex+0x4e7/0x640 lib/fault-inject.c:174 strncpy_from_user+0x3b/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:193 bpf_trace_copy_string kernel/bpf/helpers.c:760 [inline] bpf_bprintf_prepare+0xe6e/0x14a0 kernel/bpf/helpers.c:974 ____bpf_trace_printk kernel/trace/bpf_trace.c:373 [inline] bpf_trace_printk+0xda/0x190 kernel/trace/bpf_trace.c:363 bpf_prog_7c77c7e0f6645ad8+0x3e/0x44 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2258 [inline] bpf_trace_run2+0x230/0x590 kernel/trace/bpf_trace.c:2299 __bpf_trace_contention_begin+0xc9/0x110 include/trace/events/lock.h:95 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline] class_preempt_notrace_destructor include/linux/preempt.h:482 [inline] __do_trace_contention_begin include/trace/events/lock.h:95 [inline] trace_contention_begin.constprop.0+0xde/0x160 include/trace/events/lock.h:95 __pv_queued_spin_lock_slowpath+0x109/0xcf0 kernel/locking/qspinlock.c:219 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:557 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x20e/0x2b0 kernel/locking/spinlock_debug.c:116 raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline] raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599 raw_spin_rq_lock kernel/sched/sched.h:1532 [inline] rq_lock kernel/sched/sched.h:1856 [inline] __schedule+0x301/0x5de0 kernel/sched/core.c:6709 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6878 exit_to_user_mode_loop+0x67/0x110 kernel/entry/common.c:102 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f 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 *** 4 locks held by syz.0.116/6336: #0: ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline] #0: ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599 #1: ffffffff8e5c4940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #1: ffffffff8e5c4940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #1: ffffffff8e5c4940 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline] #1: ffffffff8e5c4940 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run2+0x1b6/0x590 kernel/trace/bpf_trace.c:2299 #2: ffffffff8e5b2320 (console_lock){+.+.}-{0:0}, at: _printk+0xc7/0x100 kernel/printk/printk.c:2475 #3: ffffffff8e5b2390 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:336 [inline] #3: ffffffff8e5b2390 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:346 [inline] #3: ffffffff8e5b2390 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:288 [inline] #3: ffffffff8e5b2390 (console_srcu){....}-{0:0}, at: console_flush_all+0x158/0xc60 kernel/printk/printk.c:3203 stack backtrace: CPU: 1 UID: 0 PID: 6336 Comm: syz.0.116 Not tainted 6.16.0-rc3-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x275/0x350 kernel/locking/lockdep.c:2046 check_noncircular+0x14c/0x170 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain kernel/locking/lockdep.c:3911 [inline] __lock_acquire+0x126f/0x1c90 kernel/locking/lockdep.c:5240 lock_acquire kernel/locking/lockdep.c:5871 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828 console_lock_spinning_enable+0xb0/0xd0 kernel/printk/printk.c:1924 console_emit_next_record kernel/printk/printk.c:3132 [inline] console_flush_all+0x7aa/0xc60 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 _printk+0xc7/0x100 kernel/printk/printk.c:2475 fail_dump lib/fault-inject.c:66 [inline] should_fail_ex+0x4e7/0x640 lib/fault-inject.c:174 strncpy_from_user+0x3b/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:193 bpf_trace_copy_string kernel/bpf/helpers.c:760 [inline] bpf_bprintf_prepare+0xe6e/0x14a0 kernel/bpf/helpers.c:974 ____bpf_trace_printk kernel/trace/bpf_trace.c:373 [inline] bpf_trace_printk+0xda/0x190 kernel/trace/bpf_trace.c:363 bpf_prog_7c77c7e0f6645ad8+0x3e/0x44 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2258 [inline] bpf_trace_run2+0x230/0x590 kernel/trace/bpf_trace.c:2299 __bpf_trace_contention_begin+0xc9/0x110 include/trace/events/lock.h:95 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline] class_preempt_notrace_destructor include/linux/preempt.h:482 [inline] __do_trace_contention_begin include/trace/events/lock.h:95 [inline] trace_contention_begin.constprop.0+0xde/0x160 include/trace/events/lock.h:95 __pv_queued_spin_lock_slowpath+0x109/0xcf0 kernel/locking/qspinlock.c:219 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:557 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x20e/0x2b0 kernel/locking/spinlock_debug.c:116 raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline] raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599 raw_spin_rq_lock kernel/sched/sched.h:1532 [inline] rq_lock kernel/sched/sched.h:1856 [inline] __schedule+0x301/0x5de0 kernel/sched/core.c:6709 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6878 exit_to_user_mode_loop+0x67/0x110 kernel/entry/common.c:102 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f803b98d3df Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007f803c8d8030 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: 0000000000000001 RBX: 0000000000000006 RCX: 00007f803b98d3df RDX: 0000000000000001 RSI: 00007f803c8d8090 RDI: 0000000000000006 RBP: 00007f803c8d8090 R08: 0000000000000000 R09: 00007f803c8d7df7 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f803bbb5fa0 R15: 00007ffd4144d8e8 CPU: 1 UID: 0 PID: 6336 Comm: syz.0.116 Not tainted 6.16.0-rc3-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 fail_dump lib/fault-inject.c:73 [inline] should_fail_ex+0x512/0x640 lib/fault-inject.c:174 strncpy_from_user+0x3b/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:193 bpf_trace_copy_string kernel/bpf/helpers.c:760 [inline] bpf_bprintf_prepare+0xe6e/0x14a0 kernel/bpf/helpers.c:974 ____bpf_trace_printk kernel/trace/bpf_trace.c:373 [inline] bpf_trace_printk+0xda/0x190 kernel/trace/bpf_trace.c:363 bpf_prog_7c77c7e0f6645ad8+0x3e/0x44 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2258 [inline] bpf_trace_run2+0x230/0x590 kernel/trace/bpf_trace.c:2299 __bpf_trace_contention_begin+0xc9/0x110 include/trace/events/lock.h:95 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline] class_preempt_notrace_destructor include/linux/preempt.h:482 [inline] __do_trace_contention_begin include/trace/events/lock.h:95 [inline] trace_contention_begin.constprop.0+0xde/0x160 include/trace/events/lock.h:95 __pv_queued_spin_lock_slowpath+0x109/0xcf0 kernel/locking/qspinlock.c:219 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:557 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x20e/0x2b0 kernel/locking/spinlock_debug.c:116 raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline] raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599 raw_spin_rq_lock kernel/sched/sched.h:1532 [inline] rq_lock kernel/sched/sched.h:1856 [inline] __schedule+0x301/0x5de0 kernel/sched/core.c:6709 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6878 exit_to_user_mode_loop+0x67/0x110 kernel/entry/common.c:102 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f803b98d3df Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007f803c8d8030 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: 0000000000000001 RBX: 0000000000000006 RCX: 00007f803b98d3df RDX: 0000000000000001 RSI: 00007f803c8d8090 RDI: 0000000000000006 RBP: 00007f803c8d8090 R08: 0000000000000000 R09: 00007f803c8d7df7 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f803bbb5fa0 R15: 00007ffd4144d8e8