====================================================== WARNING: possible circular locking dependency detected 5.15.180-syzkaller #0 Not tainted ------------------------------------------------------ syz.0.56/5066 is trying to acquire lock: ffff88805e7dfdb8 (&trie->lock){....}-{2:2}, at: trie_delete_elem+0x90/0x690 kernel/bpf/lpm_trie.c:467 but task is already holding lock: ffff8880b8e35c68 (lock){..-.}-{2:2}, at: local_lock_acquire+0x7/0x130 include/linux/local_lock_internal.h:28 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (lock){..-.}-{2:2}: 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:627 [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 generic_map_update_batch+0x54d/0x8b0 kernel/bpf/syscall.c:1421 bpf_map_do_batch+0x4d0/0x620 kernel/bpf/syscall.c:-1 __sys_bpf+0x55c/0x670 kernel/bpf/syscall.c:-1 __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/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #0 (&trie->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 __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 bpf_prog_1c0c44170264bb34+0x3d/0xaf4 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 __pagevec_lru_add+0x1584/0x18d0 mm/swap.c:1056 lru_cache_add+0x556/0x7e0 mm/swap.c:453 do_anonymous_page mm/memory.c:3878 [inline] handle_pte_fault mm/memory.c:4648 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x4ac5/0x5960 mm/memory.c:4883 do_user_addr_fault arch/x86/mm/fault.c:1357 [inline] handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x271/0x700 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(lock); lock(&trie->lock); lock(lock); lock(&trie->lock); *** DEADLOCK *** 5 locks held by syz.0.56/5066: #0: ffff88802b08b228 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88802b08b228 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault arch/x86/mm/fault.c:1298 [inline] #0: ffff88802b08b228 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fault arch/x86/mm/fault.c:1445 [inline] #0: ffff88802b08b228 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault+0x181/0x700 arch/x86/mm/fault.c:1501 #1: ffff888075650318 (ptlock_ptr(page)#2){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:363 [inline] #1: ffff888075650318 (ptlock_ptr(page)#2){+.+.}-{2:2}, at: do_anonymous_page mm/memory.c:3858 [inline] #1: ffff888075650318 (ptlock_ptr(page)#2){+.+.}-{2:2}, at: handle_pte_fault mm/memory.c:4648 [inline] #1: ffff888075650318 (ptlock_ptr(page)#2){+.+.}-{2:2}, at: __handle_mm_fault mm/memory.c:4785 [inline] #1: ffff888075650318 (ptlock_ptr(page)#2){+.+.}-{2:2}, at: handle_mm_fault+0x48bc/0x5960 mm/memory.c:4883 #2: ffff8880b8e354e0 (lock#5){+.+.}-{2:2}, at: local_lock_acquire+0xd/0x170 include/linux/local_lock_internal.h:28 #3: ffff8880b8e35c68 (lock){..-.}-{2:2}, at: local_lock_acquire+0x7/0x130 include/linux/local_lock_internal.h:28 #4: ffffffff8cb1f4e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 stack backtrace: CPU: 0 PID: 5066 Comm: syz.0.56 Not tainted 5.15.180-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 __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 bpf_prog_1c0c44170264bb34+0x3d/0xaf4 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 __pagevec_lru_add+0x1584/0x18d0 mm/swap.c:1056 lru_cache_add+0x556/0x7e0 mm/swap.c:453 do_anonymous_page mm/memory.c:3878 [inline] handle_pte_fault mm/memory.c:4648 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x4ac5/0x5960 mm/memory.c:4883 do_user_addr_fault arch/x86/mm/fault.c:1357 [inline] handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x271/0x700 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0033:0x7fc38238b1bc Code: 7c 10 8a 0e 74 0a 0f b7 74 16 fe 66 89 74 17 fe 88 0f c3 8b 4c 16 fc 8b 36 89 4c 17 fc 89 37 c3 c5 fa 6f 06 c5 fa 6f 4c 16 f0 fa 7f 07 c5 fa 7f 4c 17 f0 c3 66 0f 1f 84 00 00 00 00 00 48 8b RSP: 002b:00007ffe0dec6718 EFLAGS: 00010202 RAX: 0000000020001e80 RBX: 0000000000000004 RCX: ffffffffffffffee RDX: 0000000000000011 RSI: 00007fc381e45301 RDI: 0000000020001e80 RBP: 00007fc38257ca80 R08: 00007fc382245000 R09: 0000000000000022 R10: 0000000000000000 R11: 0000000000000000 R12: 000000000001d125 R13: 00007ffe0dec6820 R14: 0000000000000226 R15: fffffffffffffffe