================================
WARNING: inconsistent lock state
5.10.0-syzkaller #0 Not tainted
--------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
ksoftirqd/1/16 [HC0[0]:SC1[1]:HE1:SE0] takes:
ffff8881431860a8 (&file_data->lock){+.?.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline]
ffff8881431860a8 (&file_data->lock){+.?.}-{2:2}, at: io_file_data_ref_zero+0x75/0x480 fs/io_uring.c:7361
{SOFTIRQ-ON-W} state was registered at:
  lock_acquire kernel/locking/lockdep.c:5437 [inline]
  lock_acquire+0x29d/0x740 kernel/locking/lockdep.c:5402
  __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
  _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151
  spin_lock include/linux/spinlock.h:354 [inline]
  io_sqe_files_register fs/io_uring.c:7496 [inline]
  __io_uring_register fs/io_uring.c:9665 [inline]
  __do_sys_io_uring_register+0x338f/0x4080 fs/io_uring.c:9755
  do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
  entry_SYSCALL_64_after_hwframe+0x44/0xa9
irq event stamp: 43360928
hardirqs last  enabled at (43360928): [<ffffffff88ee1e02>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
hardirqs last  enabled at (43360928): [<ffffffff88ee1e02>] _raw_spin_unlock_irqrestore+0x42/0x50 kernel/locking/spinlock.c:191
hardirqs last disabled at (43360927): [<ffffffff88ee1bce>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]
hardirqs last disabled at (43360927): [<ffffffff88ee1bce>] _raw_spin_lock_irqsave+0x4e/0x50 kernel/locking/spinlock.c:159
softirqs last  enabled at (43360786): [<ffffffff81427a9d>] run_ksoftirqd kernel/softirq.c:653 [inline]
softirqs last  enabled at (43360786): [<ffffffff81427a9d>] run_ksoftirqd+0x2d/0x50 kernel/softirq.c:645
softirqs last disabled at (43360791): [<ffffffff81427a9d>] run_ksoftirqd kernel/softirq.c:653 [inline]
softirqs last disabled at (43360791): [<ffffffff81427a9d>] run_ksoftirqd+0x2d/0x50 kernel/softirq.c:645

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&file_data->lock);
  <Interrupt>
    lock(&file_data->lock);

 *** DEADLOCK ***

2 locks held by ksoftirqd/1/16:
 #0: ffffffff8b339f40 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2479 [inline]
 #0: ffffffff8b339f40 (rcu_callback){....}-{0:0}, at: rcu_core+0x582/0xf00 kernel/rcu/tree.c:2723
 #1: ffffffff8b33a060 (rcu_read_lock){....}-{1:2}, at: percpu_ref_put_many.constprop.0+0x0/0x250 net/netfilter/xt_cgroup.c:62

stack backtrace:
CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.10.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 print_usage_bug kernel/locking/lockdep.c:3740 [inline]
 valid_state kernel/locking/lockdep.c:3751 [inline]
 mark_lock_irq kernel/locking/lockdep.c:3954 [inline]
 mark_lock.cold+0x31/0x73 kernel/locking/lockdep.c:4411
 mark_usage kernel/locking/lockdep.c:4306 [inline]
 __lock_acquire+0x11a5/0x5500 kernel/locking/lockdep.c:4786
 lock_acquire kernel/locking/lockdep.c:5437 [inline]
 lock_acquire+0x29d/0x740 kernel/locking/lockdep.c:5402
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:354 [inline]
 io_file_data_ref_zero+0x75/0x480 fs/io_uring.c:7361
 percpu_ref_put_many.constprop.0+0x217/0x250 include/linux/percpu-refcount.h:322
 rcu_do_batch kernel/rcu/tree.c:2489 [inline]
 rcu_core+0x5eb/0xf00 kernel/rcu/tree.c:2723
 __do_softirq+0x2a0/0x9f6 kernel/softirq.c:298
 run_ksoftirqd kernel/softirq.c:653 [inline]
 run_ksoftirqd+0x2d/0x50 kernel/softirq.c:645
 smpboot_thread_fn+0x655/0x9e0 kernel/smpboot.c:165
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296