============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
ksoftirqd/1/21 is trying to acquire lock:
ffffc900059190d8 (&rb->spinlock){..-.}-{2:2}, at: __bpf_ringbuf_reserve+0x1c4/0x5a0 kernel/bpf/ringbuf.c:413

but task is already holding lock:
ffffc90005f9e0d8 (&rb->spinlock){..-.}-{2:2}, at: __bpf_ringbuf_reserve+0x1c4/0x5a0 kernel/bpf/ringbuf.c:413

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

       CPU0
       ----
  lock(&rb->spinlock);
  lock(&rb->spinlock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

4 locks held by ksoftirqd/1/21:
 #0: ffffffff8cb2ad00 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8cb2ad00 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2291 [inline]
 #0: ffffffff8cb2ad00 (rcu_callback){....}-{0:0}, at: rcu_core+0x94e/0x16a0 kernel/rcu/tree.c:2557
 #1: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #1: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #1: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline]
 #1: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run3+0xf0/0x400 kernel/trace/bpf_trace.c:2325
 #2: ffffc90005f9e0d8 (&rb->spinlock){..-.}-{2:2}, at: __bpf_ringbuf_reserve+0x1c4/0x5a0 kernel/bpf/ringbuf.c:413
 #3: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #3: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #3: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline]
 #3: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xda/0x3b0 kernel/trace/bpf_trace.c:2324

stack backtrace:
CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
 __lock_acquire+0x122f/0x7c50 kernel/locking/lockdep.c:-1
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
 __bpf_ringbuf_reserve+0x1c4/0x5a0 kernel/bpf/ringbuf.c:413
 ____bpf_ringbuf_output kernel/bpf/ringbuf.c:539 [inline]
 bpf_ringbuf_output+0x65/0x1e0 kernel/bpf/ringbuf.c:529
 bpf_prog_fab844a31c87a330+0x45/0x49
 bpf_dispatcher_nop_func include/linux/bpf.h:1011 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline]
 bpf_trace_run2+0x1cd/0x3b0 kernel/trace/bpf_trace.c:2324
 trace_contention_end+0x13f/0x190 include/trace/events/lock.h:122
 __pv_queued_spin_lock_slowpath+0x7e8/0x9c0 kernel/locking/qspinlock.c:560
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline]
 queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x217/0x280 kernel/locking/spinlock_debug.c:115
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0xb0/0xf0 kernel/locking/spinlock.c:162
 __bpf_ringbuf_reserve+0x1c4/0x5a0 kernel/bpf/ringbuf.c:413
 ____bpf_ringbuf_reserve kernel/bpf/ringbuf.c:464 [inline]
 bpf_ringbuf_reserve+0x58/0x70 kernel/bpf/ringbuf.c:456
 bpf_prog_fe0ed97373b08409+0x25/0x42
 bpf_dispatcher_nop_func include/linux/bpf.h:1011 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline]
 bpf_trace_run3+0x1e3/0x400 kernel/trace/bpf_trace.c:2325
 __bpf_trace_kmem_cache_free+0x99/0xc0 include/trace/events/kmem.h:114
 __traceiter_kmem_cache_free+0x30/0x50 include/trace/events/kmem.h:114
 trace_kmem_cache_free include/trace/events/kmem.h:114 [inline]
 kmem_cache_free+0x1ef/0x290 mm/slub.c:3708
 rcu_do_batch kernel/rcu/tree.c:2297 [inline]
 rcu_core+0x9c0/0x16a0 kernel/rcu/tree.c:2557
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 run_ksoftirqd+0x98/0xf0 kernel/softirq.c:963
 smpboot_thread_fn+0x64a/0xa40 kernel/smpboot.c:164
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>