============================================ WARNING: possible recursive locking detected 6.8.0-syzkaller-05238-g61df575632d6 #0 Not tainted -------------------------------------------- syz-executor.2/7002 is trying to acquire lock: ffffc9000b7350d8 (&rb->spinlock){-.-.}-{2:2}, at: __bpf_ringbuf_reserve+0x211/0x4f0 kernel/bpf/ringbuf.c:424 but task is already holding lock: ffffc9000b6b10d8 (&rb->spinlock){-.-.}-{2:2}, at: __bpf_ringbuf_reserve+0x211/0x4f0 kernel/bpf/ringbuf.c:424 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&rb->spinlock); lock(&rb->spinlock); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz-executor.2/7002: #0: ffffffff8e17cf88 (tracepoints_mutex){+.+.}-{3:3}, at: tracepoint_probe_unregister+0x32/0x990 kernel/tracepoint.c:548 #1: ffffffff8e17cf40 (tracepoints_mutex.wait_lock){+.+.}-{2:2}, at: __mutex_lock_common kernel/locking/mutex.c:706 [inline] #1: ffffffff8e17cf40 (tracepoints_mutex.wait_lock){+.+.}-{2:2}, at: __mutex_lock+0x7fc/0xd70 kernel/locking/mutex.c:752 #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2389 [inline] #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1fc/0x530 kernel/trace/bpf_trace.c:2431 #3: ffffc9000b6b10d8 (&rb->spinlock){-.-.}-{2:2}, at: __bpf_ringbuf_reserve+0x211/0x4f0 kernel/bpf/ringbuf.c:424 #4: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #4: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #4: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2389 [inline] #4: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1fc/0x530 kernel/trace/bpf_trace.c:2431 stack backtrace: CPU: 0 PID: 7002 Comm: syz-executor.2 Not tainted 6.8.0-syzkaller-05238-g61df575632d6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 check_deadlock kernel/locking/lockdep.c:3062 [inline] validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 __bpf_ringbuf_reserve+0x211/0x4f0 kernel/bpf/ringbuf.c:424 ____bpf_ringbuf_reserve kernel/bpf/ringbuf.c:459 [inline] bpf_ringbuf_reserve+0x5c/0x70 kernel/bpf/ringbuf.c:451 bpf_prog_9efe54833449f08e+0x2d/0x47 bpf_dispatcher_nop_func include/linux/bpf.h:1233 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2390 [inline] bpf_trace_run2+0x2ec/0x530 kernel/trace/bpf_trace.c:2431 __traceiter_contention_end+0x7b/0xb0 include/trace/events/lock.h:122 trace_contention_end+0xf6/0x120 include/trace/events/lock.h:122 __pv_queued_spin_lock_slowpath+0x939/0xc60 kernel/locking/qspinlock.c:560 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [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 __bpf_ringbuf_reserve+0x211/0x4f0 kernel/bpf/ringbuf.c:424 ____bpf_ringbuf_reserve kernel/bpf/ringbuf.c:459 [inline] bpf_ringbuf_reserve+0x5c/0x70 kernel/bpf/ringbuf.c:451 bpf_prog_9efe54833449f08e+0x2d/0x47 bpf_dispatcher_nop_func include/linux/bpf.h:1233 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2390 [inline] bpf_trace_run2+0x2ec/0x530 kernel/trace/bpf_trace.c:2431 __traceiter_contention_end+0x7b/0xb0 include/trace/events/lock.h:122 trace_contention_end+0xd7/0x100 include/trace/events/lock.h:122 __mutex_lock_common kernel/locking/mutex.c:727 [inline] __mutex_lock+0x991/0xd70 kernel/locking/mutex.c:752 tracepoint_probe_unregister+0x32/0x990 kernel/tracepoint.c:548 bpf_raw_tp_link_release+0x45/0x70 kernel/bpf/syscall.c:3477 bpf_link_free kernel/bpf/syscall.c:3033 [inline] bpf_link_put_direct+0x123/0x1b0 kernel/bpf/syscall.c:3064 bpf_link_release+0x3b/0x50 kernel/bpf/syscall.c:3071 __fput+0x429/0x8a0 fs/file_table.c:423 __do_sys_close fs/open.c:1557 [inline] __se_sys_close fs/open.c:1542 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1542 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f188387cc9a Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24 RSP: 002b:00007ffdc7944d00 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00007f188387cc9a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000032 R08: 0000001b2e960000 R09: 00007f18839abf8c R10: 00007ffdc7944e50 R11: 0000000000000293 R12: 00007f1883400a30 R13: ffffffffffffffff R14: 00007f1883400000 R15: 000000000001c1fa