====================================================== WARNING: possible circular locking dependency detected 5.15.179-syzkaller #0 Not tainted ------------------------------------------------------ syz.1.122/4597 is trying to acquire lock: ffff8880b8e35c68 (lock){-.-.}-{2:2}, at: local_lock_acquire+0x7/0x130 include/linux/local_lock_internal.h:28 but task is already holding lock: ffff888024de79b8 (&trie->lock){....}-{2:2}, at: trie_update_elem+0xcf/0xca0 kernel/bpf/lpm_trie.c:323 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&trie->lock){....}-{2:2}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 trie_delete_elem+0x90/0x690 kernel/bpf/lpm_trie.c:467 0xffffffffa00021da bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline] bpf_trace_run1+0x168/0x2f0 kernel/trace/bpf_trace.c:1914 __bpf_trace_mm_page_free_batched+0x41/0x60 include/trace/events/kmem.h:182 trace_mm_page_free_batched include/trace/events/kmem.h:182 [inline] free_unref_page_list+0x79b/0x8e0 mm/page_alloc.c:3465 release_pages+0x1bb9/0x1f40 mm/swap.c:963 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline] tlb_flush_mmu_free mm/mmu_gather.c:240 [inline] tlb_flush_mmu mm/mmu_gather.c:247 [inline] tlb_finish_mmu+0x177/0x320 mm/mmu_gather.c:338 exit_mmap+0x3cd/0x620 mm/mmap.c:3206 __mmput+0x112/0x3b0 kernel/fork.c:1127 exit_mm+0x688/0x7f0 kernel/exit.c:550 do_exit+0x626/0x2480 kernel/exit.c:861 do_group_exit+0x144/0x310 kernel/exit.c:996 get_signal+0xc66/0x14e0 kernel/signal.c:2900 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #0 (lock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 local_lock_acquire+0x23/0x130 include/linux/local_lock_internal.h:29 rmqueue_pcplist mm/page_alloc.c:3699 [inline] rmqueue mm/page_alloc.c:3742 [inline] get_page_from_freelist+0x3227/0x3d40 mm/page_alloc.c:4189 __alloc_pages+0x272/0x700 mm/page_alloc.c:5466 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xbb/0x4b0 mm/slub.c:1975 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] __kmalloc_node+0x1fa/0x390 mm/slub.c:4451 kmalloc_node include/linux/slab.h:614 [inline] bpf_map_kmalloc_node+0xdb/0x160 kernel/bpf/syscall.c:430 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:290 [inline] trie_update_elem+0x1d7/0xca0 kernel/bpf/lpm_trie.c:332 bpf_map_update_value+0x5d7/0x6c0 kernel/bpf/syscall.c:221 map_update_elem+0x6a0/0x7c0 kernel/bpf/syscall.c:1185 __sys_bpf+0x2fd/0x670 kernel/bpf/syscall.c:4636 __do_sys_bpf kernel/bpf/syscall.c:4752 [inline] __se_sys_bpf kernel/bpf/syscall.c:4750 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4750 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&trie->lock); lock(lock); lock(&trie->lock); lock(lock); *** DEADLOCK *** 2 locks held by syz.1.122/4597: #0: ffffffff8cb1f4e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 #1: ffff888024de79b8 (&trie->lock){....}-{2:2}, at: trie_update_elem+0xcf/0xca0 kernel/bpf/lpm_trie.c:323 stack backtrace: CPU: 0 PID: 4597 Comm: syz.1.122 Not tainted 5.15.179-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 local_lock_acquire+0x23/0x130 include/linux/local_lock_internal.h:29 rmqueue_pcplist mm/page_alloc.c:3699 [inline] rmqueue mm/page_alloc.c:3742 [inline] get_page_from_freelist+0x3227/0x3d40 mm/page_alloc.c:4189 __alloc_pages+0x272/0x700 mm/page_alloc.c:5466 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xbb/0x4b0 mm/slub.c:1975 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] __kmalloc_node+0x1fa/0x390 mm/slub.c:4451 kmalloc_node include/linux/slab.h:614 [inline] bpf_map_kmalloc_node+0xdb/0x160 kernel/bpf/syscall.c:430 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:290 [inline] trie_update_elem+0x1d7/0xca0 kernel/bpf/lpm_trie.c:332 bpf_map_update_value+0x5d7/0x6c0 kernel/bpf/syscall.c:221 map_update_elem+0x6a0/0x7c0 kernel/bpf/syscall.c:1185 __sys_bpf+0x2fd/0x670 kernel/bpf/syscall.c:4636 __do_sys_bpf kernel/bpf/syscall.c:4752 [inline] __se_sys_bpf kernel/bpf/syscall.c:4750 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4750 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f7b9705e169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7b94ec7038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f7b97276fa0 RCX: 00007f7b9705e169 RDX: 0000000000000020 RSI: 00002000000004c0 RDI: 0000000000000002 RBP: 00007f7b970df2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7b97276fa0 R15: 00007ffee7007118