IPVS: lblc: UDP 224.0.0.2:0 - no destination available ============================================ WARNING: possible recursive locking detected 6.12.0-rc5-syzkaller-00308-g3e5e6c9900c3 #0 Not tainted -------------------------------------------- swapper/0/0 is trying to acquire lock: ffffc900272090d8 (&rb->spinlock){-.-.}-{2:2}, at: __bpf_ringbuf_reserve+0x36e/0x4b0 kernel/bpf/ringbuf.c:427 but task is already holding lock: ffffc90025e310d8 (&rb->spinlock){-.-.}-{2:2}, at: __bpf_ringbuf_reserve+0x36e/0x4b0 kernel/bpf/ringbuf.c:427 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 6 locks held by swapper/0/0: #0: ffffc9002e08fba0 (&x->wait#28){-.-.}-{2:2}, at: complete_with_flags kernel/sched/completion.c:20 [inline] #0: ffffc9002e08fba0 (&x->wait#28){-.-.}-{2:2}, at: complete+0x1d/0x200 kernel/sched/completion.c:47 #1: ffff888022435298 (&p->pi_lock){-.-.}-{2:2}, at: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline] #1: ffff888022435298 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xa1/0x14f0 kernel/sched/core.c:4165 #2: ffff88802b63ee98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline] #2: ffff88802b63ee98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591 #3: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #3: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #3: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2315 [inline] #3: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1c2/0x590 kernel/trace/bpf_trace.c:2357 #4: ffffc90025e310d8 (&rb->spinlock){-.-.}-{2:2}, at: __bpf_ringbuf_reserve+0x36e/0x4b0 kernel/bpf/ringbuf.c:427 #5: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #5: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #5: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2315 [inline] #5: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1c2/0x590 kernel/trace/bpf_trace.c:2357 stack backtrace: CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.0-rc5-syzkaller-00308-g3e5e6c9900c3 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_deadlock_bug+0x2e3/0x410 kernel/locking/lockdep.c:3037 check_deadlock kernel/locking/lockdep.c:3089 [inline] validate_chain kernel/locking/lockdep.c:3891 [inline] __lock_acquire+0x2185/0x3ce0 kernel/locking/lockdep.c:5202 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 __bpf_ringbuf_reserve+0x36e/0x4b0 kernel/bpf/ringbuf.c:427 ____bpf_ringbuf_reserve kernel/bpf/ringbuf.c:478 [inline] bpf_ringbuf_reserve+0x57/0x90 kernel/bpf/ringbuf.c:470 bpf_prog_0e153dac479590bf+0x35/0x70 bpf_dispatcher_nop_func include/linux/bpf.h:1265 [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:2316 [inline] bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2357 __traceiter_contention_begin+0x5a/0xa0 include/trace/events/lock.h:95 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:94 [inline] trace_contention_begin.constprop.0+0xed/0x170 include/trace/events/lock.h:95 __pv_queued_spin_lock_slowpath+0x10b/0xc90 kernel/locking/qspinlock.c:402 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [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+0x210/0x2c0 kernel/locking/spinlock_debug.c:116 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0x42/0x60 kernel/locking/spinlock.c:162 __bpf_ringbuf_reserve+0x36e/0x4b0 kernel/bpf/ringbuf.c:427 ____bpf_ringbuf_reserve kernel/bpf/ringbuf.c:478 [inline] bpf_ringbuf_reserve+0x57/0x90 kernel/bpf/ringbuf.c:470 bpf_prog_0e153dac479590bf+0x35/0x70 bpf_dispatcher_nop_func include/linux/bpf.h:1265 [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:2316 [inline] bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2357 __traceiter_contention_begin+0x5a/0xa0 include/trace/events/lock.h:95 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:94 [inline] trace_contention_begin.constprop.0+0xed/0x170 include/trace/events/lock.h:95 __pv_queued_spin_lock_slowpath+0x10b/0xc90 kernel/locking/qspinlock.c:402 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [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+0x210/0x2c0 kernel/locking/spinlock_debug.c:116 raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline] raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591 raw_spin_rq_lock kernel/sched/sched.h:1505 [inline] rq_lock kernel/sched/sched.h:1804 [inline] ttwu_queue kernel/sched/core.c:3951 [inline] try_to_wake_up+0x52e/0x14f0 kernel/sched/core.c:4281 swake_up_locked kernel/sched/swait.c:29 [inline] swake_up_locked kernel/sched/swait.c:21 [inline] complete_with_flags kernel/sched/completion.c:24 [inline] complete+0xb0/0x200 kernel/sched/completion.c:47 csd_do_func kernel/smp.c:134 [inline] __flush_smp_call_function_queue+0x41f/0x8c0 kernel/smp.c:571 __sysvec_call_function_single+0x8c/0x410 arch/x86/kernel/smp.c:271 instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline] sysvec_call_function_single+0x9f/0xc0 arch/x86/kernel/smp.c:266 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline] RIP: 0010:default_idle+0xf/0x20 arch/x86/kernel/process.c:743 Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d d3 14 32 00 fb f4 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 RSP: 0018:ffffffff8da07e20 EFLAGS: 00000206 RAX: 0000000000437947 RBX: 0000000000000000 RCX: ffffffff8b146dc9 RDX: 0000000000000000 RSI: ffffffff8b4cc8e0 RDI: ffffffff8bb135a0 RBP: fffffbfff1b52af8 R08: 0000000000000001 R09: ffffed1005687025 R10: ffff88802b43812b R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff8da957c0 R14: ffffffff901cf388 R15: 0000000000000000 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x32c/0x3f0 kernel/sched/idle.c:326 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:424 rest_init+0x16b/0x2b0 init/main.c:747 start_kernel+0x3e4/0x4d0 init/main.c:1105 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x148 IPVS: lblc: UDP 224.0.0.2:0 - no destination available IPVS: lblc: UDP 224.0.0.2:0 - no destination available IPVS: lblc: UDP 224.0.0.2:0 - no destination available IPVS: lblc: UDP 224.0.0.2:0 - no destination available IPVS: lblc: UDP 224.0.0.2:0 - no destination available IPVS: lblc: UDP 224.0.0.2:0 - no destination available IPVS: lblc: UDP 224.0.0.2:0 - no destination available IPVS: lblc: UDP 224.0.0.2:0 - no destination available IPVS: lblc: UDP 224.0.0.2:0 - no destination available ---------------- Code disassembly (best guess): 0: 4c 01 c7 add %r8,%rdi 3: 4c 29 c2 sub %r8,%rdx 6: e9 72 ff ff ff jmp 0xffffff7d b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: f3 0f 1e fa endbr64 1f: eb 07 jmp 0x28 21: 0f 00 2d d3 14 32 00 verw 0x3214d3(%rip) # 0x3214fb 28: fb sti 29: f4 hlt * 2a: fa cli <-- trapping instruction 2b: c3 ret 2c: cc int3 2d: cc int3 2e: cc int3 2f: cc int3 30: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1) 37: 00 00 00 00 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop