============================================ WARNING: possible recursive locking detected syzkaller #0 Not tainted -------------------------------------------- syz.8.195/6991 is trying to acquire lock: ffff888062843218 (&qs->lock){..-.}-{2:2}, at: __queue_map_get+0x11c/0x4b0 kernel/bpf/queue_stack_maps.c:105 but task is already holding lock: ffff88805ead7a18 (&qs->lock){..-.}-{2:2}, at: __queue_map_get+0x11c/0x4b0 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 5 locks held by syz.8.195/6991: #0: ffff88802bb59a20 (&sig->exec_update_lock){++++}-{3:3}, at: __do_sys_perf_event_open kernel/events/core.c:12706 [inline] #0: ffff88802bb59a20 (&sig->exec_update_lock){++++}-{3:3}, at: __se_sys_perf_event_open+0x93a/0x1c20 kernel/events/core.c:12567 #1: ffff8880219734a8 (&ctx->mutex){+.+.}-{3:3}, at: __do_sys_perf_event_open kernel/events/core.c:12730 [inline] #1: ffff8880219734a8 (&ctx->mutex){+.+.}-{3:3}, at: __se_sys_perf_event_open+0xaec/0x1c20 kernel/events/core.c:12567 #2: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #2: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #2: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2321 [inline] #2: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xde/0x3c0 kernel/trace/bpf_trace.c:2361 #3: ffff88805ead7a18 (&qs->lock){..-.}-{2:2}, at: __queue_map_get+0x11c/0x4b0 kernel/bpf/queue_stack_maps.c:105 #4: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #4: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #4: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2321 [inline] #4: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xde/0x3c0 kernel/trace/bpf_trace.c:2361 stack backtrace: CPU: 1 PID: 6991 Comm: syz.8.195 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 check_deadlock kernel/locking/lockdep.c:3062 [inline] validate_chain kernel/locking/lockdep.c:3856 [inline] __lock_acquire+0x5d40/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa8/0xf0 kernel/locking/spinlock.c:162 __queue_map_get+0x11c/0x4b0 kernel/bpf/queue_stack_maps.c:105 bpf_prog_00798911c748094f+0x42/0x46 bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:612 [inline] bpf_prog_run include/linux/filter.h:619 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2322 [inline] bpf_trace_run2+0x1d1/0x3c0 kernel/trace/bpf_trace.c:2361 __bpf_trace_contention_end+0xdd/0x130 include/trace/events/lock.h:122 trace_contention_end+0xe6/0x110 include/trace/events/lock.h:122 __pv_queued_spin_lock_slowpath+0x7ec/0x9d0 kernel/locking/qspinlock.c:560 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:586 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x24e/0x2c0 kernel/locking/spinlock_debug.c:115 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0xb4/0xf0 kernel/locking/spinlock.c:162 __queue_map_get+0x11c/0x4b0 kernel/bpf/queue_stack_maps.c:105 bpf_prog_94b194d4ebfffdd5+0x45/0x49 bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:612 [inline] bpf_prog_run include/linux/filter.h:619 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2322 [inline] bpf_trace_run2+0x1d1/0x3c0 kernel/trace/bpf_trace.c:2361 trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0xf8/0x1a0 mm/slab_common.c:1043 find_get_pmu_context+0x8de/0x9e0 kernel/events/core.c:4956 __do_sys_perf_event_open kernel/events/core.c:12821 [inline] __se_sys_perf_event_open+0xb49/0x1c20 kernel/events/core.c:12567 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5fa918f749 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:00007f5faa00e038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f5fa93e6090 RCX: 00007f5fa918f749 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000500 RBP: 00007f5fa9213f91 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5fa93e6128 R14: 00007f5fa93e6090 R15: 00007fff9e0b5298