syzbot

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WARNING: possible circular locking dependency detected
6.13.0-rc3-next-20241218-syzkaller #0 Not tainted
------------------------------------------------------
kworker/0:1/9 is trying to acquire lock:
ffffffff8e813680 (console_owner){-...}-{0:0}, at: console_trylock_spinning kernel/printk/printk.c:2048 [inline]
ffffffff8e813680 (console_owner){-...}-{0:0}, at: vprintk_emit+0x530/0xa10 kernel/printk/printk.c:2431

but task is already holding lock:
ffff8880b863e118 (&pool->lock){-.-.}-{2:2}, at: start_flush_work kernel/workqueue.c:4144 [inline]
ffff8880b863e118 (&pool->lock){-.-.}-{2:2}, at: __flush_work+0x1a9/0xc50 kernel/workqueue.c:4195

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&pool->lock){-.-.}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
       __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
       _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
       __queue_work+0x759/0xf50
       queue_work_on+0x1c2/0x380 kernel/workqueue.c:2390
       queue_work include/linux/workqueue.h:662 [inline]
       rpm_suspend+0xe70/0x1730 drivers/base/power/runtime.c:662
       __pm_runtime_idle+0x131/0x1a0 drivers/base/power/runtime.c:1104
       pm_runtime_put include/linux/pm_runtime.h:448 [inline]
       __device_attach+0x3e5/0x520 drivers/base/dd.c:1048
       bus_probe_device+0x189/0x260 drivers/base/bus.c:534
       device_add+0x856/0xbf0 drivers/base/core.c:3665
       serial_base_port_add+0x2b6/0x3f0 drivers/tty/serial/serial_base_bus.c:179
       serial_core_port_device_add drivers/tty/serial/serial_core.c:3344 [inline]
       serial_core_register_port+0x377/0x2870 drivers/tty/serial/serial_core.c:3383
       serial8250_register_8250_port+0x1545/0x1ec0 drivers/tty/serial/8250/8250_core.c:820
       serial_pnp_probe+0x4f9/0x9d0 drivers/tty/serial/8250/8250_pnp.c:490
       pnp_device_probe+0x2ba/0x460 drivers/pnp/driver.c:111
       really_probe+0x2b9/0xad0 drivers/base/dd.c:658
       __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800
       driver_probe_device+0x50/0x430 drivers/base/dd.c:830
       __driver_attach+0x45f/0x710 drivers/base/dd.c:1216
       bus_for_each_dev+0x239/0x2b0 drivers/base/bus.c:370
       bus_add_driver+0x346/0x670 drivers/base/bus.c:675
       driver_register+0x23a/0x320 drivers/base/driver.c:246
       serial8250_init+0xc1/0x1c0 drivers/tty/serial/8250/8250_platform.c:324
       do_one_initcall+0x248/0x870 init/main.c:1267
       do_initcall_level+0x157/0x210 init/main.c:1329
       do_initcalls+0x3f/0x80 init/main.c:1345
       kernel_init_freeable+0x435/0x5d0 init/main.c:1578
       kernel_init+0x1d/0x2b0 init/main.c:1467
       ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

-> #2 (&dev->power.lock){-.-.}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       __pm_runtime_resume+0x112/0x180 drivers/base/power/runtime.c:1171
       pm_runtime_get include/linux/pm_runtime.h:396 [inline]
       __uart_start+0x17c/0x450 drivers/tty/serial/serial_core.c:148
       uart_write+0x280/0xa40 drivers/tty/serial/serial_core.c:635
       process_output_block drivers/tty/n_tty.c:574 [inline]
       n_tty_write+0xd62/0x1230 drivers/tty/n_tty.c:2389
       iterate_tty_write drivers/tty/tty_io.c:1015 [inline]
       file_tty_write+0x546/0x9b0 drivers/tty/tty_io.c:1090
       new_sync_write fs/read_write.c:586 [inline]
       vfs_write+0xacf/0xd10 fs/read_write.c:679
       ksys_write+0x18f/0x2b0 fs/read_write.c:731
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&port_lock_key){-.-.}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       uart_port_lock_irqsave include/linux/serial_core.h:715 [inline]
       serial8250_console_write+0x1a7/0x1ed0 drivers/tty/serial/8250/8250_port.c:3372
       console_emit_next_record kernel/printk/printk.c:3122 [inline]
       console_flush_all+0x86b/0xeb0 kernel/printk/printk.c:3210
       __console_flush_and_unlock kernel/printk/printk.c:3269 [inline]
       console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309
       vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432
       _printk+0xd5/0x120 kernel/printk/printk.c:2457
       register_console+0xbf5/0xfd0 kernel/printk/printk.c:4099
       univ8250_console_init+0x52/0x90 drivers/tty/serial/8250/8250_core.c:513
       console_init+0x1b8/0x6f0 kernel/printk/printk.c:4292
       start_kernel+0x2dd/0x510 init/main.c:1038
       x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:515
       x86_64_start_kernel+0x9f/0xa0 arch/x86/kernel/head64.c:496
       common_startup_64+0x13e/0x147

-> #0 (console_owner){-...}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3161 [inline]
       check_prevs_add kernel/locking/lockdep.c:3280 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
       __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
       console_trylock_spinning kernel/printk/printk.c:2048 [inline]
       vprintk_emit+0x54d/0xa10 kernel/printk/printk.c:2431
       _printk+0xd5/0x120 kernel/printk/printk.c:2457
       __warn_printk+0x237/0x360 kernel/panic.c:794
       check_flush_dependency+0x2ee/0x390 kernel/workqueue.c:3704
       start_flush_work kernel/workqueue.c:4158 [inline]
       __flush_work+0x286/0xc50 kernel/workqueue.c:4195
       flush_work kernel/workqueue.c:4252 [inline]
       flush_delayed_work+0x169/0x1c0 kernel/workqueue.c:4274
       hfs_file_fsync+0xea/0x140 fs/hfs/inode.c:680
       generic_write_sync include/linux/fs.h:2952 [inline]
       dio_complete+0x55c/0x6b0 fs/direct-io.c:313
       process_one_work kernel/workqueue.c:3229 [inline]
       process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
       worker_thread+0x870/0xd30 kernel/workqueue.c:3391
       kthread+0x7a9/0x920 kernel/kthread.c:464
       ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

other info that might help us debug this:

Chain exists of:
  console_owner --> &dev->power.lock --> &pool->lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&pool->lock);
                               lock(&dev->power.lock);
                               lock(&pool->lock);
  lock(console_owner);

 *** DEADLOCK ***

5 locks held by kworker/0:1/9:
 #0: ffff8880274aed48 ((wq_completion)dio/loop4){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff8880274aed48 ((wq_completion)dio/loop4){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310
 #1: ffffc900000e7c60 ((work_completion)(&dio->complete_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
 #1: ffffc900000e7c60 ((work_completion)(&dio->complete_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310
 #2: ffff88802a329620 (&sb->s_type->i_mutex_key#27){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:863 [inline]
 #2: ffff88802a329620 (&sb->s_type->i_mutex_key#27){+.+.}-{4:4}, at: hfs_file_fsync+0x95/0x140 fs/hfs/inode.c:673
 #3: ffffffff8e937d20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #3: ffffffff8e937d20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #3: ffffffff8e937d20 (rcu_read_lock){....}-{1:3}, at: start_flush_work kernel/workqueue.c:4137 [inline]
 #3: ffffffff8e937d20 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xe7/0xc50 kernel/workqueue.c:4195
 #4: ffff8880b863e118 (&pool->lock){-.-.}-{2:2}, at: start_flush_work kernel/workqueue.c:4144 [inline]
 #4: ffff8880b863e118 (&pool->lock){-.-.}-{2:2}, at: __flush_work+0x1a9/0xc50 kernel/workqueue.c:4195

stack backtrace:
CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Not tainted 6.13.0-rc3-next-20241218-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
Workqueue: dio/loop4 dio_aio_complete_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
 check_prev_add kernel/locking/lockdep.c:3161 [inline]
 check_prevs_add kernel/locking/lockdep.c:3280 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
 console_trylock_spinning kernel/printk/printk.c:2048 [inline]
 vprintk_emit+0x54d/0xa10 kernel/printk/printk.c:2431
 _printk+0xd5/0x120 kernel/printk/printk.c:2457
 __warn_printk+0x237/0x360 kernel/panic.c:794
 check_flush_dependency+0x2ee/0x390 kernel/workqueue.c:3704
 start_flush_work kernel/workqueue.c:4158 [inline]
 __flush_work+0x286/0xc50 kernel/workqueue.c:4195
 flush_work kernel/workqueue.c:4252 [inline]
 flush_delayed_work+0x169/0x1c0 kernel/workqueue.c:4274
 hfs_file_fsync+0xea/0x140 fs/hfs/inode.c:680
 generic_write_sync include/linux/fs.h:2952 [inline]
 dio_complete+0x55c/0x6b0 fs/direct-io.c:313
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
workqueue: WQ_MEM_RECLAIM dio/loop4:dio_aio_complete_work is flushing !WQ_MEM_RECLAIM events_long:flush_mdb
WARNING: CPU: 0 PID: 9 at kernel/workqueue.c:3708 check_flush_dependency+0x2ef/0x390 kernel/workqueue.c:3704
Modules linked in:
CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Not tainted 6.13.0-rc3-next-20241218-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
Workqueue: dio/loop4 dio_aio_complete_work
RIP: 0010:check_flush_dependency+0x2ef/0x390 kernel/workqueue.c:3704
Code: e7 e8 45 ed 9d 00 49 8b 14 24 48 8b 4c 24 08 48 81 c1 78 01 00 00 48 c7 c7 60 d2 09 8c 4c 89 ee 4c 8b 04 24 e8 72 3f f8 ff 90 <0f> 0b 90 90 e9 63 ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 66
RSP: 0018:ffffc900000e77b8 EFLAGS: 00010046
RAX: 9a34564af5aef900 RBX: ffff888028aeac08 RCX: ffff88801ce80000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000008 R08: ffffffff817ffa32 R09: 1ffff110170c519a
R10: dffffc0000000000 R11: ffffed10170c519b R12: ffff88801cad7818
R13: ffff8880274aed78 R14: dffffc0000000000 R15: ffff88801cad7820
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3050bff8 CR3: 0000000032b66000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 start_flush_work kernel/workqueue.c:4158 [inline]
 __flush_work+0x286/0xc50 kernel/workqueue.c:4195
 flush_work kernel/workqueue.c:4252 [inline]
 flush_delayed_work+0x169/0x1c0 kernel/workqueue.c:4274
 hfs_file_fsync+0xea/0x140 fs/hfs/inode.c:680
 generic_write_sync include/linux/fs.h:2952 [inline]
 dio_complete+0x55c/0x6b0 fs/direct-io.c:313
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>