====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz-executor/7512 is trying to acquire lock: ffff88805c940a38 (&trie->lock){-...}-{2:2}, at: trie_delete_elem+0x94/0x630 kernel/bpf/lpm_trie.c:466 but task is already holding lock: ffff8880b8f37de8 (stock_lock){-.-.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff8880b8f37de8 (stock_lock){-.-.}-{2:2}, at: refill_stock+0xea/0x450 mm/memcontrol.c:2355 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (stock_lock){-.-.}-{2:2}: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] consume_obj_stock mm/memcontrol.c:3267 [inline] obj_cgroup_charge+0x10a/0x630 mm/memcontrol.c:3397 memcg_slab_pre_alloc_hook mm/slab.h:508 [inline] slab_pre_alloc_hook+0x2e2/0x300 mm/slab.h:719 slab_alloc_node mm/slub.c:3477 [inline] __kmem_cache_alloc_node+0x53/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node+0xa6/0x240 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] bpf_map_kmalloc_node+0xbc/0x1b0 kernel/bpf/syscall.c:424 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:291 [inline] trie_update_elem+0x172/0xd60 kernel/bpf/lpm_trie.c:338 bpf_map_update_value+0x64b/0x710 kernel/bpf/syscall.c:203 generic_map_update_batch+0x5de/0x800 kernel/bpf/syscall.c:1800 bpf_map_do_batch+0x3f2/0x600 kernel/bpf/syscall.c:5011 __sys_bpf+0x381/0x890 kernel/bpf/syscall.c:-1 __do_sys_bpf kernel/bpf/syscall.c:5582 [inline] __se_sys_bpf kernel/bpf/syscall.c:5580 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5580 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&trie->lock){-...}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x37ef/0x7d80 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb4/0x100 kernel/locking/spinlock.c:162 trie_delete_elem+0x94/0x630 kernel/bpf/lpm_trie.c:466 bpf_prog_2c29ac5cdc6b1842+0x42/0x46 bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:606 [inline] bpf_prog_run include/linux/filter.h:624 [inline] bpf_prog_run_array include/linux/bpf.h:1994 [inline] trace_call_bpf+0x3ad/0x6c0 kernel/trace/bpf_trace.c:143 perf_trace_run_bpf_submit+0x7a/0x1c0 kernel/events/core.c:10287 perf_trace_lock_acquire+0x342/0x400 include/trace/events/lock.h:24 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x3ef/0x420 kernel/locking/lockdep.c:5725 rcu_lock_acquire include/linux/rcupdate.h:334 [inline] rcu_read_lock include/linux/rcupdate.h:786 [inline] percpu_ref_put_many include/linux/percpu-refcount.h:330 [inline] percpu_ref_put+0x35/0x180 include/linux/percpu-refcount.h:351 css_put include/linux/cgroup_refcnt.h:79 [inline] drain_stock mm/memcontrol.c:2304 [inline] __refill_stock+0x12a/0x3d0 mm/memcontrol.c:2341 refill_stock+0x19e/0x450 mm/memcontrol.c:2356 try_charge_memcg+0x1281/0x17c0 mm/memcontrol.c:2807 try_charge mm/memcontrol.c:2865 [inline] charge_memcg+0x11b/0x3b0 mm/memcontrol.c:7090 __mem_cgroup_charge+0x25/0x80 mm/memcontrol.c:7111 mem_cgroup_charge include/linux/memcontrol.h:686 [inline] wp_page_copy mm/memory.c:3118 [inline] do_wp_page+0x1378/0x34d0 mm/memory.c:3469 handle_pte_fault mm/memory.c:5063 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x1306/0x4a50 mm/memory.c:5353 do_user_addr_fault+0xad2/0x12d0 arch/x86/mm/fault.c:1322 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(stock_lock); lock(&trie->lock); lock(stock_lock); lock(&trie->lock); *** DEADLOCK *** 3 locks held by syz-executor/7512: #0: ffff88805e635730 (&vma->vm_lock->lock){++++}-{3:3}, at: vma_start_read include/linux/mm.h:669 [inline] #0: ffff88805e635730 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x249/0x660 mm/memory.c:5509 #1: ffff8880b8f37de8 (stock_lock){-.-.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] #1: ffff8880b8f37de8 (stock_lock){-.-.}-{2:2}, at: refill_stock+0xea/0x450 mm/memcontrol.c:2355 #2: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #2: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #2: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: trace_call_bpf+0xc3/0x6c0 kernel/trace/bpf_trace.c:142 stack backtrace: CPU: 1 PID: 7512 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 check_noncircular+0x2fc/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x37ef/0x7d80 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb4/0x100 kernel/locking/spinlock.c:162 trie_delete_elem+0x94/0x630 kernel/bpf/lpm_trie.c:466 bpf_prog_2c29ac5cdc6b1842+0x42/0x46 bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:606 [inline] bpf_prog_run include/linux/filter.h:624 [inline] bpf_prog_run_array include/linux/bpf.h:1994 [inline] trace_call_bpf+0x3ad/0x6c0 kernel/trace/bpf_trace.c:143 perf_trace_run_bpf_submit+0x7a/0x1c0 kernel/events/core.c:10287 perf_trace_lock_acquire+0x342/0x400 include/trace/events/lock.h:24 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x3ef/0x420 kernel/locking/lockdep.c:5725 rcu_lock_acquire include/linux/rcupdate.h:334 [inline] rcu_read_lock include/linux/rcupdate.h:786 [inline] percpu_ref_put_many include/linux/percpu-refcount.h:330 [inline] percpu_ref_put+0x35/0x180 include/linux/percpu-refcount.h:351 css_put include/linux/cgroup_refcnt.h:79 [inline] drain_stock mm/memcontrol.c:2304 [inline] __refill_stock+0x12a/0x3d0 mm/memcontrol.c:2341 refill_stock+0x19e/0x450 mm/memcontrol.c:2356 try_charge_memcg+0x1281/0x17c0 mm/memcontrol.c:2807 try_charge mm/memcontrol.c:2865 [inline] charge_memcg+0x11b/0x3b0 mm/memcontrol.c:7090 __mem_cgroup_charge+0x25/0x80 mm/memcontrol.c:7111 mem_cgroup_charge include/linux/memcontrol.h:686 [inline] wp_page_copy mm/memory.c:3118 [inline] do_wp_page+0x1378/0x34d0 mm/memory.c:3469 handle_pte_fault mm/memory.c:5063 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x1306/0x4a50 mm/memory.c:5353 do_user_addr_fault+0xad2/0x12d0 arch/x86/mm/fault.c:1322 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f9c5d963527 Code: 00 00 00 80 3d d1 92 df 00 00 0f 84 b4 00 00 00 48 c7 c0 e0 ff ff ff c7 05 ca 92 df 00 00 00 00 00 64 48 8b 08 48 85 c9 74 0b <48> c7 81 80 08 00 00 01 00 00 00 48 c7 05 a3 92 df 00 00 00 00 00 RSP: 002b:00007ffdb9beae18 EFLAGS: 00010202 RAX: ffffffffffffffe0 RBX: 0000000000000000 RCX: 00007f9c5dbf1e20 RDX: 0000000000000000 RSI: 00007f9c5da556e0 RDI: 00007f9c5e758060 RBP: 00007ffdb9beaf7c R08: 00007f9c5e758060 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000000927c0 R14: 000000000002edd6 R15: 00007ffdb9beafd0