BUG: workqueue leaked atomic, lock or RCU: kworker/1:4[5339]
     preempt=0x00000000 lock=0->1 RCU=0->0 workfn=smc_ib_port_event_work
1 lock held by kworker/1:4/5339:
 #0: ffffffff8fcd1d48 (rtnl_mutex){+.+.}-{3:3}, at: ib_get_eth_speed+0x13c/0x800 drivers/infiniband/core/verbs.c:1991
CPU: 1 UID: 0 PID: 5339 Comm: kworker/1:4 Not tainted 6.12.0-rc2-syzkaller-00003-g89e9ae55dc56-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events smc_ib_port_event_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 process_one_work kernel/workqueue.c:3250 [inline]
 process_scheduled_works+0x1158/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 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>

======================================================
WARNING: possible circular locking dependency detected
6.12.0-rc2-syzkaller-00003-g89e9ae55dc56-dirty #0 Not tainted
------------------------------------------------------
kworker/1:4/5339 is trying to acquire lock:
ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310

but task is already holding lock:
ffffffff8fcd1d48 (rtnl_mutex){+.+.}-{3:3}, at: ib_get_eth_speed+0x13c/0x800 drivers/infiniband/core/verbs.c:1991

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (rtnl_mutex){+.+.}-{3:3}:
       reacquire_held_locks+0x3eb/0x690 kernel/locking/lockdep.c:5350
       __lock_release kernel/locking/lockdep.c:5539 [inline]
       lock_release+0x396/0xa30 kernel/locking/lockdep.c:5846
       process_one_work kernel/workqueue.c:3236 [inline]
       process_scheduled_works+0xb70/0x1850 kernel/workqueue.c:3310
       worker_thread+0x870/0xd30 kernel/workqueue.c:3391
       kthread+0x2f0/0x390 kernel/kthread.c:389
       ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

-> #0 ((wq_completion)events){+.+.}-{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+0x1384/0x2050 kernel/locking/lockdep.c:5202
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
       process_one_work kernel/workqueue.c:3204 [inline]
       process_scheduled_works+0x950/0x1850 kernel/workqueue.c:3310
       worker_thread+0x870/0xd30 kernel/workqueue.c:3391
       kthread+0x2f0/0x390 kernel/kthread.c:389
       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:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(rtnl_mutex);
                               lock((wq_completion)events);
                               lock(rtnl_mutex);
  lock((wq_completion)events);

 *** DEADLOCK ***

1 lock held by kworker/1:4/5339:
 #0: ffffffff8fcd1d48 (rtnl_mutex){+.+.}-{3:3}, at: ib_get_eth_speed+0x13c/0x800 drivers/infiniband/core/verbs.c:1991

stack backtrace:
CPU: 1 UID: 0 PID: 5339 Comm: kworker/1:4 Not tainted 6.12.0-rc2-syzkaller-00003-g89e9ae55dc56-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events wq_barrier_func
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+0x1384/0x2050 kernel/locking/lockdep.c:5202
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
 process_one_work kernel/workqueue.c:3204 [inline]
 process_scheduled_works+0x950/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 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>
BUG: workqueue leaked atomic, lock or RCU: kworker/1:4[5339]
     preempt=0x00000000 lock=1->0 RCU=0->0 workfn=wq_barrier_func
INFO: lockdep is turned off.
CPU: 1 UID: 0 PID: 5339 Comm: kworker/1:4 Not tainted 6.12.0-rc2-syzkaller-00003-g89e9ae55dc56-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events wq_barrier_func
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 process_one_work kernel/workqueue.c:3250 [inline]
 process_scheduled_works+0x1158/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 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>