ODEBUG: object ffffc90003e37b48 is on stack ffffc90003e34000, but NOT annotated. ====================================================== WARNING: possible circular locking dependency detected 6.15.0-rc4-syzkaller #0 Not tainted ------------------------------------------------------ bch-copygc/loop/4998 is trying to acquire lock: ffffffff83d83370 (console_owner){....}-{0:0}, at: console_trylock_spinning kernel/printk/printk.c:2048 [inline] ffffffff83d83370 (console_owner){....}-{0:0}, at: vprintk_emit+0x1b2/0x420 kernel/printk/printk.c:2449 but task is already holding lock: ffffffff8beedb60 (&obj_hash[i].lock){-.-.}-{2:2}, at: __debug_object_init+0x5e/0x2b0 lib/debugobjects.c:741 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&obj_hash[i].lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x5f/0x90 kernel/locking/spinlock.c:162 debug_object_activate+0x6f/0x340 lib/debugobjects.c:818 debug_work_activate kernel/workqueue.c:664 [inline] insert_work+0x24/0xc0 kernel/workqueue.c:2180 __queue_work+0x47a/0x5d0 kernel/workqueue.c:2341 queue_work_on+0xc0/0x110 kernel/workqueue.c:2392 queue_work include/linux/workqueue.h:662 [inline] start_poll_synchronize_rcu_expedited+0x99/0xd0 kernel/rcu/tree_exp.h:1075 rcu_init+0xea/0x120 kernel/rcu/tree.c:4846 start_kernel+0x1ac/0x380 init/main.c:990 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:513 x86_64_start_kernel+0x61/0x70 arch/x86/kernel/head64.c:494 common_startup_64+0x13e/0x147 -> #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+0x2b6/0x5d0 kernel/workqueue.c:-1 queue_work_on+0xc0/0x110 kernel/workqueue.c:2392 queue_work include/linux/workqueue.h:662 [inline] rpm_suspend+0x4ea/0x720 drivers/base/power/runtime.c:673 __pm_runtime_idle+0x68/0xa0 drivers/base/power/runtime.c:1112 pm_runtime_put include/linux/pm_runtime.h:466 [inline] __device_attach+0x11c/0x1a0 drivers/base/dd.c:1047 bus_probe_device+0x9e/0x120 drivers/base/bus.c:537 device_add+0x253/0x440 drivers/base/core.c:3692 serial_base_port_add+0xde/0x150 drivers/tty/serial/serial_base_bus.c:179 serial_core_port_device_add drivers/tty/serial/serial_core.c:3342 [inline] serial_core_register_port+0xfd/0x980 drivers/tty/serial/serial_core.c:3381 serial8250_register_8250_port+0x59f/0x6f0 drivers/tty/serial/8250/8250_core.c:822 serial_pnp_probe+0x1cf/0x310 drivers/tty/serial/8250/8250_pnp.c:480 pnp_device_probe+0xcd/0x120 drivers/pnp/driver.c:111 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0xfb/0x3e0 drivers/base/dd.c:657 __driver_probe_device+0x72/0xf0 drivers/base/dd.c:799 driver_probe_device+0x1d/0x1b0 drivers/base/dd.c:829 __driver_attach+0x11b/0x270 drivers/base/dd.c:1215 bus_for_each_dev+0x104/0x150 drivers/base/bus.c:370 bus_add_driver+0x167/0x2b0 drivers/base/bus.c:678 driver_register+0x64/0x110 drivers/base/driver.c:249 serial8250_init+0x6f/0x110 drivers/tty/serial/8250/8250_platform.c:315 do_one_initcall+0x144/0x440 init/main.c:1257 do_initcall_level+0x7d/0xa0 init/main.c:1319 do_initcalls+0x54/0x90 init/main.c:1335 kernel_init_freeable+0x185/0x200 init/main.c:1567 kernel_init+0x15/0x120 init/main.c:1457 ret_from_fork+0x32/0x40 arch/x86/kernel/process.c:153 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+0x5f/0x90 kernel/locking/spinlock.c:162 __pm_runtime_resume+0x4a/0x80 drivers/base/power/runtime.c:1179 pm_runtime_get include/linux/pm_runtime.h:414 [inline] __uart_start+0x53/0xe0 drivers/tty/serial/serial_core.c:148 uart_write+0xca/0x2a0 drivers/tty/serial/serial_core.c:635 process_output_block drivers/tty/n_tty.c:561 [inline] n_tty_write+0x33f/0x4b0 drivers/tty/n_tty.c:2377 iterate_tty_write drivers/tty/tty_io.c:1015 [inline] file_tty_write+0x1e0/0x350 drivers/tty/tty_io.c:1090 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x2c0/0x3b0 fs/read_write.c:684 ksys_write+0x74/0xf0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 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+0x5f/0x90 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] serial8250_console_write+0x7e/0x850 drivers/tty/serial/8250/8250_port.c:3415 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x340/0x510 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0x65/0x100 kernel/printk/printk.c:3325 vprintk_emit+0x26a/0x420 kernel/printk/printk.c:2450 _printk+0x57/0x80 kernel/printk/printk.c:2475 register_console+0x35d/0x3f0 kernel/printk/printk.c:4125 univ8250_console_init+0x1e/0x40 drivers/tty/serial/8250/8250_core.c:513 console_init+0x9e/0x280 kernel/printk/printk.c:4323 start_kernel+0x25b/0x380 init/main.c:1034 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:513 x86_64_start_kernel+0x61/0x70 arch/x86/kernel/head64.c:494 common_startup_64+0x13e/0x147 -> #0 (console_owner){....}-{0:0}: check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain kernel/locking/lockdep.c:3909 [inline] __lock_acquire+0x14dc/0x2790 kernel/locking/lockdep.c:5235 lock_acquire+0x103/0x340 kernel/locking/lockdep.c:5866 console_trylock_spinning kernel/printk/printk.c:2048 [inline] vprintk_emit+0x1cf/0x420 kernel/printk/printk.c:2449 _printk+0x57/0x80 kernel/printk/printk.c:2475 debug_object_is_on_stack lib/debugobjects.c:-1 [inline] lookup_object_or_alloc lib/debugobjects.c:688 [inline] __debug_object_init+0x215/0x2b0 lib/debugobjects.c:743 rhashtable_init_noprof+0x2e4/0x340 lib/rhashtable.c:1085 bch2_copygc_thread+0x11f/0x5a0 fs/bcachefs/movinggc.c:360 kthread+0x23c/0x270 kernel/kthread.c:464 ret_from_fork+0x32/0x40 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 other info that might help us debug this: Chain exists of: console_owner --> &pool->lock --> &obj_hash[i].lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&obj_hash[i].lock); lock(&pool->lock); lock(&obj_hash[i].lock); lock(console_owner); *** DEADLOCK *** 1 lock held by bch-copygc/loop/4998: #0: ffffffff8beedb60 (&obj_hash[i].lock){-.-.}-{2:2}, at: __debug_object_init+0x5e/0x2b0 lib/debugobjects.c:741 stack backtrace: CPU: 1 UID: 0 PID: 4998 Comm: bch-copygc/loop Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(undef) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0xad/0x110 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2079 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2211 check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain kernel/locking/lockdep.c:3909 [inline] __lock_acquire+0x14dc/0x2790 kernel/locking/lockdep.c:5235 lock_acquire+0x103/0x340 kernel/locking/lockdep.c:5866 console_trylock_spinning kernel/printk/printk.c:2048 [inline] vprintk_emit+0x1cf/0x420 kernel/printk/printk.c:2449 _printk+0x57/0x80 kernel/printk/printk.c:2475 debug_object_is_on_stack lib/debugobjects.c:-1 [inline] lookup_object_or_alloc lib/debugobjects.c:688 [inline] __debug_object_init+0x215/0x2b0 lib/debugobjects.c:743 rhashtable_init_noprof+0x2e4/0x340 lib/rhashtable.c:1085 bch2_copygc_thread+0x11f/0x5a0 fs/bcachefs/movinggc.c:360 kthread+0x23c/0x270 kernel/kthread.c:464 ret_from_fork+0x32/0x40 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 4998 at lib/debugobjects.c:655 debug_object_is_on_stack lib/debugobjects.c:655 [inline] WARNING: CPU: 1 PID: 4998 at lib/debugobjects.c:655 lookup_object_or_alloc lib/debugobjects.c:688 [inline] WARNING: CPU: 1 PID: 4998 at lib/debugobjects.c:655 __debug_object_init+0x219/0x2b0 lib/debugobjects.c:743 Modules linked in: CPU: 1 UID: 0 PID: 4998 Comm: bch-copygc/loop Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(undef) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:debug_object_is_on_stack lib/debugobjects.c:655 [inline] RIP: 0010:lookup_object_or_alloc lib/debugobjects.c:688 [inline] RIP: 0010:__debug_object_init+0x219/0x2b0 lib/debugobjects.c:743 Code: 89 0d 2b 00 0d 0a 48 c7 c1 7e 18 a4 83 48 c7 c7 10 f5 86 83 40 84 f6 48 0f 45 f9 48 89 de 49 89 c6 e8 ab d6 34 ff 4c 89 f0 90 <0f> 0b 90 e9 cf fe ff ff e8 7a 11 00 00 8b 05 fc c4 fe 01 3b 05 fa RSP: 0018:ffffc90003e37a78 EFLAGS: 00010046 RAX: ffff888103322d70 RBX: ffffc90003e37b48 RCX: 3fea801e6bcf9400 RDX: ffff8882b300c000 RSI: ffffffff838c571f RDI: 00000000ffffffff RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 5b5d303938383439 R11: ffffffff82089fe0 R12: 0000000000000286 R13: ffffffff83015b70 R14: ffff888103322d70 R15: ffffffff8beedb48 FS: 0000000000000000(0000) GS:ffff8882b300c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f26cff71da0 CR3: 0000000179e84000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rhashtable_init_noprof+0x2e4/0x340 lib/rhashtable.c:1085 bch2_copygc_thread+0x11f/0x5a0 fs/bcachefs/movinggc.c:360 kthread+0x23c/0x270 kernel/kthread.c:464 ret_from_fork+0x32/0x40 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245