============================================ WARNING: possible recursive locking detected 6.14.0-rc1-syzkaller-g0fc6025c95c8 #0 Not tainted -------------------------------------------- syz.1.83/6130 is trying to acquire lock: ffff888077c571e0 (&qs->lock){..-.}-{2:2}, at: __stack_map_get+0x14b/0x4b0 kernel/bpf/queue_stack_maps.c:140 but task is already holding lock: ffff888147ec51e0 (&qs->lock){..-.}-{2:2}, at: __queue_map_get+0x14b/0x4d0 kernel/bpf/queue_stack_maps.c:105 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 3 locks held by syz.1.83/6130: #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: bpf_test_timer_enter+0x19/0x140 net/bpf/test_run.c:40 #1: ffff888147ec51e0 (&qs->lock){..-.}-{2:2}, at: __queue_map_get+0x14b/0x4d0 kernel/bpf/queue_stack_maps.c:105 #2: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #2: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #2: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2370 [inline] #2: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run2+0x1fc/0x540 kernel/trace/bpf_trace.c:2412 stack backtrace: CPU: 1 UID: 0 PID: 6130 Comm: syz.1.83 Not tainted 6.14.0-rc1-syzkaller-g0fc6025c95c8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3039 check_deadlock kernel/locking/lockdep.c:3091 [inline] validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3893 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 __stack_map_get+0x14b/0x4b0 kernel/bpf/queue_stack_maps.c:140 bpf_prog_00798911c748094f+0x43/0x47 bpf_dispatcher_nop_func include/linux/bpf.h:1291 [inline] __bpf_prog_run include/linux/filter.h:701 [inline] bpf_prog_run include/linux/filter.h:708 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2371 [inline] bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2412 __bpf_trace_contention_end+0x170/0x230 include/trace/events/lock.h:122 __do_trace_contention_end include/trace/events/lock.h:122 [inline] trace_contention_end+0x118/0x140 include/trace/events/lock.h:122 __pv_queued_spin_lock_slowpath+0xb7e/0xdb0 kernel/locking/qspinlock.c:557 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:577 [inline] queued_spin_lock_slowpath+0x42/0x50 arch/x86/include/asm/qspinlock.h:51 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x272/0x370 kernel/locking/spinlock_debug.c:116 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0xe1/0x120 kernel/locking/spinlock.c:162 __queue_map_get+0x14b/0x4d0 kernel/bpf/queue_stack_maps.c:105 bpf_prog_94b194d4ebfffdd5+0x46/0x4a bpf_dispatcher_nop_func include/linux/bpf.h:1291 [inline] __bpf_prog_run include/linux/filter.h:701 [inline] bpf_prog_run include/linux/filter.h:708 [inline] bpf_test_run+0x4f0/0xa90 net/bpf/test_run.c:434 bpf_prog_test_run_skb+0xcaa/0x1830 net/bpf/test_run.c:1096 bpf_prog_test_run+0x2e4/0x360 kernel/bpf/syscall.c:4407 __sys_bpf+0x487/0x820 kernel/bpf/syscall.c:5813 __do_sys_bpf kernel/bpf/syscall.c:5902 [inline] __se_sys_bpf kernel/bpf/syscall.c:5900 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5900 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd0a8f8cde9 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:00007fd0a9e08038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fd0a91a5fa0 RCX: 00007fd0a8f8cde9 RDX: 0000000000000050 RSI: 0000400000000000 RDI: 000000000000000a RBP: 00007fd0a900e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd0a91a5fa0 R15: 00007ffda9fda6f8