============================================
WARNING: possible recursive locking detected
6.1.60-syzkaller #0 Not tainted
--------------------------------------------
syz-executor.2/6339 is trying to acquire lock:
ffff8880b9828358 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x120/0x260 kernel/time/timer.c:999

but task is already holding lock:
ffff8880b9928358 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x120/0x260 kernel/time/timer.c:999

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

       CPU0
       ----
  lock(&base->lock);
  lock(&base->lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

4 locks held by syz-executor.2/6339:
 #0: ffffffff8d12a060 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline]
 #0: ffffffff8d12a060 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline]
 #0: ffffffff8d12a060 (rcu_read_lock){....}-{1:2}, at: bpf_map_update_value+0x207/0x6f0 kernel/bpf/syscall.c:225
 #1: ffff88802f7269f8 (&trie->lock){....}-{2:2}, at: trie_update_elem+0xc5/0xc00 kernel/bpf/lpm_trie.c:321
 #2: ffff8880b9928118 (krc.lock){..-.}-{2:2}, at: krc_this_cpu_lock kernel/rcu/tree.c:2945 [inline]
 #2: ffff8880b9928118 (krc.lock){..-.}-{2:2}, at: add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3265 [inline]
 #2: ffff8880b9928118 (krc.lock){..-.}-{2:2}, at: kvfree_call_rcu+0x1b2/0x8c0 kernel/rcu/tree.c:3356
 #3: ffff8880b9928358 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x120/0x260 kernel/time/timer.c:999

stack backtrace:
CPU: 1 PID: 6339 Comm: syz-executor.2 Not tainted 6.1.60-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2983 [inline]
 check_deadlock kernel/locking/lockdep.c:3026 [inline]
 validate_chain+0x4726/0x58e0 kernel/locking/lockdep.c:3811
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5048
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5661
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 lock_timer_base+0x120/0x260 kernel/time/timer.c:999
 __mod_timer+0x1cb/0xee0 kernel/time/timer.c:1072
 queue_delayed_work_on+0x156/0x250 kernel/workqueue.c:1704
 free_pages_prepare mm/page_alloc.c:1446 [inline]
 free_pcp_prepare mm/page_alloc.c:1490 [inline]
 free_unref_page_prepare+0x319/0x1120 mm/page_alloc.c:3358
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3453
 __stack_depot_save+0x409/0x470 lib/stackdepot.c:506
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x60/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422
 kmem_cache_zalloc include/linux/slab.h:679 [inline]
 fill_pool lib/debugobjects.c:168 [inline]
 debug_objects_fill_pool+0x4c9/0xa10 lib/debugobjects.c:606
 debug_object_activate+0x134/0x890 lib/debugobjects.c:702
 debug_timer_activate kernel/time/timer.c:782 [inline]
 __mod_timer+0x7bf/0xee0 kernel/time/timer.c:1103
 queue_delayed_work_on+0x156/0x250 kernel/workqueue.c:1704
 queue_delayed_work include/linux/workqueue.h:519 [inline]
 schedule_delayed_monitor_work kernel/rcu/tree.c:3126 [inline]
 kvfree_call_rcu+0x520/0x8c0 kernel/rcu/tree.c:3374
 trie_update_elem+0x808/0xc00 kernel/bpf/lpm_trie.c:382
 bpf_map_update_value+0x5cf/0x6f0 kernel/bpf/syscall.c:226
 generic_map_update_batch+0x4e8/0x880 kernel/bpf/syscall.c:1656
 bpf_map_do_batch+0x4d0/0x620
 __sys_bpf+0x658/0x6c0
 __do_sys_bpf kernel/bpf/syscall.c:5072 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5070 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5070
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f18de27cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f18df0450c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f18de39bf80 RCX: 00007f18de27cae9
RDX: 0000000000000038 RSI: 0000000020000640 RDI: 000000000000001a
RBP: 00007f18de2c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f18de39bf80 R15: 00007ffe2b8883e8
 </TASK>