============================================ WARNING: possible recursive locking detected 6.1.141-syzkaller #0 Not tainted -------------------------------------------- kworker/u4:4/56 is trying to acquire lock: ffff88805a41d218 (&qs->lock){-.-.}-{2:2}, at: __queue_map_get+0x118/0x4a0 kernel/bpf/queue_stack_maps.c:109 but task is already holding lock: ffff888058564218 (&qs->lock){-.-.}-{2:2}, at: __queue_map_get+0x118/0x4a0 kernel/bpf/queue_stack_maps.c:109 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&qs->lock); lock(&qs->lock); *** DEADLOCK *** May be due to missing lock nesting notation 7 locks held by kworker/u4:4/56: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc90001577d00 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffff88805712e2f8 (&devlink->lock_key#4){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x53/0xaf0 drivers/net/netdevsim/dev.c:838 #3: ffff8881437574e0 (&nsim_trap_data->trap_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #3: ffff8881437574e0 (&nsim_trap_data->trap_lock){+.+.}-{2:2}, at: nsim_dev_trap_report drivers/net/netdevsim/dev.c:791 [inline] #3: ffff8881437574e0 (&nsim_trap_data->trap_lock){+.+.}-{2:2}, at: nsim_dev_trap_report_work+0x1a1/0xaf0 drivers/net/netdevsim/dev.c:851 #4: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #4: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #4: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline] #4: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xda/0x3b0 kernel/trace/bpf_trace.c:2324 #5: ffff888058564218 (&qs->lock){-.-.}-{2:2}, at: __queue_map_get+0x118/0x4a0 kernel/bpf/queue_stack_maps.c:109 #6: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #6: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #6: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline] #6: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xda/0x3b0 kernel/trace/bpf_trace.c:2324 stack backtrace: CPU: 1 PID: 56 Comm: kworker/u4:4 Not tainted 6.1.141-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound nsim_dev_trap_report_work Call Trace: 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 __queue_map_get+0x118/0x4a0 kernel/bpf/queue_stack_maps.c:109 bpf_prog_00798911c748094f+0x3a/0x3e bpf_dispatcher_nop_func include/linux/bpf.h:1001 [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 __queue_map_get+0x118/0x4a0 kernel/bpf/queue_stack_maps.c:109 bpf_prog_94b194d4ebfffdd5+0x3d/0x41 bpf_dispatcher_nop_func include/linux/bpf.h:1001 [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 __bpf_trace_kfree+0x6e/0x90 include/trace/events/kmem.h:94 trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0xf6/0x190 mm/slab_common.c:975 skb_free_head net/core/skbuff.c:762 [inline] skb_release_data+0x5db/0x7c0 net/core/skbuff.c:791 skb_release_all net/core/skbuff.c:856 [inline] __kfree_skb net/core/skbuff.c:870 [inline] consume_skb+0xa2/0x100 net/core/skbuff.c:1035 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] nsim_dev_trap_report_work+0x76b/0xaf0 drivers/net/netdevsim/dev.c:851 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295