rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7715/3:b..l rcu: (detected by 0, t=10502 jiffies, g=27701, q=555 ncpus=2) task:kworker/u8:8 state:R running task stack:23688 pid:7715 tgid:7715 ppid:2 task_flags:0x4208160 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7090 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:60 [inline] RIP: 0010:stack_access_ok+0x8e/0x200 arch/x86/kernel/unwind_orc.c:393 Code: 00 00 00 fc ff df 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 0b 01 00 00 8b 13 85 d2 74 23 49 39 ef 77 1e 48 39 e9 76 19 <4a> 8d 54 25 00 49 39 d7 0f 92 c0 48 39 d1 0f 93 c2 20 d0 0f 85 ba RSP: 0018:ffffc90003997338 EFLAGS: 00000212 RAX: 0000000000000000 RBX: ffffc900039973e8 RCX: ffffc90003998000 RDX: 0000000000000001 RSI: ffffc90003997758 RDI: ffffc900039973e8 RBP: ffffc90003997758 R08: ffffffff91ab954c R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000084fe7 R12: 0000000000000008 R13: ffffc900039973f8 R14: ffffc900039973f0 R15: ffffc90003990000 deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] unwind_next_frame+0xb7d/0x20a0 arch/x86/kernel/unwind_orc.c:585 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 ref_tracker_alloc+0x1d2/0x5b0 lib/ref_tracker.c:209 __netdev_tracker_alloc include/linux/netdevice.h:4331 [inline] netdev_hold include/linux/netdevice.h:4360 [inline] netdev_hold include/linux/netdevice.h:4355 [inline] ___neigh_create+0x7d8/0x28c0 net/core/neighbour.c:616 ip6_finish_output2+0x1299/0x2020 net/ipv6/ip6_output.c:132 __ip6_finish_output net/ipv6/ip6_output.c:215 [inline] ip6_finish_output+0x3f9/0x1360 net/ipv6/ip6_output.c:226 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip6_output+0x1f9/0x540 net/ipv6/ip6_output.c:247 dst_output include/net/dst.h:459 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] ndisc_send_skb+0xa91/0x1e40 net/ipv6/ndisc.c:513 ndisc_send_rs+0x129/0x670 net/ipv6/ndisc.c:723 addrconf_dad_completed+0x49d/0x10d0 net/ipv6/addrconf.c:4360 addrconf_dad_work+0x84d/0x14e0 net/ipv6/addrconf.c:4268 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread timer wakeup didn't happen for 10526 jiffies! g27701 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=19329 rcu: rcu_preempt kthread starved for 10527 jiffies! g27701 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:I stack:28712 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 1294 Comm: aoe_tx0 Not tainted 6.14.0-syzkaller-13524-gf4d2ef48250a #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:__sanitizer_cov_trace_pc+0x41/0x70 kernel/kcov.c:217 Code: a9 00 01 ff 00 74 1d f6 c4 01 74 43 a9 00 00 0f 00 75 3c a9 00 00 f0 00 75 35 8b 82 3c 16 00 00 85 c0 74 2b 8b 82 18 16 00 00 <83> f8 02 75 20 48 8b 8a 20 16 00 00 8b 92 1c 16 00 00 48 8b 01 48 RSP: 0018:ffffc900043079b8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff88802cbbf170 RCX: ffffffff8942c6f5 RDX: ffff888028e72440 RSI: ffffffff8942c734 RDI: ffff888030196e98 RBP: ffff888030196dc0 R08: 0000000000000004 R09: 0000000000000020 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000020 R13: 0000000000000020 R14: 0000000000000000 R15: ffff888033d00000 FS: 0000000000000000(0000) GS:ffff8881249b3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000032000 CR3: 000000007a686000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_pull+0x114/0x190 net/core/skbuff.c:2625 handle_tx+0x358/0x630 drivers/net/caif/caif_serial.c:235 __netdev_start_xmit include/linux/netdevice.h:5201 [inline] netdev_start_xmit include/linux/netdevice.h:5210 [inline] xmit_one net/core/dev.c:3783 [inline] dev_hard_start_xmit+0x93/0x740 net/core/dev.c:3799 __dev_queue_xmit+0x7eb/0x43e0 net/core/dev.c:4636 dev_queue_xmit include/linux/netdevice.h:3350 [inline] tx+0xcc/0x190 drivers/block/aoe/aoenet.c:62 kthread+0x1e1/0x3e0 drivers/block/aoe/aoecmd.c:1237 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245