rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=b74c/1/0x4000000000000000 softirq=151489/151490 fqs=98 rcu: (t=10500 jiffies g=249453 q=440 ncpus=2) rcu: rcu_preempt kthread starved for 10298 jiffies! g249453 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 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:R running task stack:28320 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0xee1/0x59f0 kernel/sched/core.c:6710 schedule+0xe7/0x1b0 kernel/sched/core.c:6786 schedule_timeout+0x157/0x2c0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x1ec/0xa50 kernel/rcu/tree.c:1609 rcu_gp_kthread+0x249/0x380 kernel/rcu/tree.c:1808 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296 RIP: 0000:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.5.0-rc2-syzkaller-00052-gbfa3037d8280 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 RIP: 0010:kvm_wait+0xa8/0x110 arch/x86/kernel/kvm.c:1064 Code: fa 83 e2 07 38 d0 7f 04 84 c0 75 66 0f b6 07 40 38 c6 74 1b 48 83 c4 10 c3 c3 e8 c3 bc 53 00 66 90 0f 00 2d 9a 2d 30 09 fb f4 <48> 83 c4 10 c3 66 90 0f 00 2d 8a 2d 30 09 f4 48 83 c4 10 c3 89 74 RSP: 0018:ffffc900001dfb78 EFLAGS: 00000246 RAX: 00000000010cbf66 RBX: ffff88802cb5e0f0 RCX: 1ffffffff23133e6 RDX: 0000000000000000 RSI: ffffffff8a6c7700 RDI: ffffffff8ac806e0 RBP: ffff8880b993d240 R08: 0000000000000001 R09: fffffbfff23095e8 R10: ffffffff9184af47 R11: 0000000000000016 R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000000 R15: ffffed100596bc1e FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3efde71d58 CR3: 000000000c776000 CR4: 00000000003526e0 Call Trace: pv_wait arch/x86/include/asm/paravirt.h:598 [inline] pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline] __pv_queued_spin_lock_slowpath+0x959/0xc70 kernel/locking/qspinlock.c:511 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+0x20e/0x2b0 kernel/locking/spinlock_debug.c:115 spin_lock include/linux/spinlock.h:351 [inline] __dev_xmit_skb net/core/dev.c:3796 [inline] __dev_queue_xmit+0x20f0/0x3f20 net/core/dev.c:4169 dev_queue_xmit include/linux/netdevice.h:3088 [inline] br_dev_queue_push_xmit+0x26e/0x7b0 net/bridge/br_forward.c:53 NF_HOOK include/linux/netfilter.h:303 [inline] NF_HOOK include/linux/netfilter.h:297 [inline] br_forward_finish+0x12a/0x480 net/bridge/br_forward.c:66 NF_HOOK include/linux/netfilter.h:303 [inline] NF_HOOK include/linux/netfilter.h:297 [inline] __br_forward+0x38b/0x900 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver+0x354/0x450 net/bridge/br_forward.c:189 br_flood+0x17e/0x640 net/bridge/br_forward.c:235 br_dev_xmit+0xeac/0x1970 net/bridge/br_device.c:100 __netdev_start_xmit include/linux/netdevice.h:4910 [inline] netdev_start_xmit include/linux/netdevice.h:4924 [inline] xmit_one net/core/dev.c:3537 [inline] dev_hard_start_xmit+0x13d/0x6c0 net/core/dev.c:3553 __dev_queue_xmit+0xa55/0x3f20 net/core/dev.c:4203 dev_queue_xmit include/linux/netdevice.h:3088 [inline] neigh_resolve_output net/core/neighbour.c:1552 [inline] neigh_resolve_output+0x58c/0x900 net/core/neighbour.c:1532 neigh_output include/net/neighbour.h:544 [inline] ip6_finish_output2+0x5d0/0x1b20 net/ipv6/ip6_output.c:135 __ip6_finish_output net/ipv6/ip6_output.c:196 [inline] ip6_finish_output+0x485/0x11d0 net/ipv6/ip6_output.c:207 NF_HOOK_COND include/linux/netfilter.h:292 [inline] ip6_output+0x243/0x890 net/ipv6/ip6_output.c:228 dst_output include/net/dst.h:458 [inline] NF_HOOK.constprop.0+0xfd/0x540 include/linux/netfilter.h:303 ndisc_send_skb+0x9e8/0x1430 net/ipv6/ndisc.c:508 ndisc_send_rs+0x133/0x690 net/ipv6/ndisc.c:718 addrconf_rs_timer+0x412/0x840 net/ipv6/addrconf.c:3935 call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x764/0xb10 kernel/time/timer.c:2022 run_timer_softirq+0x58/0xd0 kernel/time/timer.c:2035 __do_softirq+0x218/0x965 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1109 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 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:72 [inline] RIP: 0010:__intel_idle_hlt drivers/idle/intel_idle.c:206 [inline] RIP: 0010:intel_idle_hlt+0x11/0x20 drivers/idle/intel_idle.c:224 Code: 48 89 de 48 c7 c7 20 f6 3f 8d e8 1a 92 1d fa e9 51 ff ff ff 0f 1f 44 00 00 f3 0f 1e fa 89 d0 66 90 0f 00 2d 31 8d 9c 00 fb f4 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 89 d0 fb RSP: 0018:ffffc90000177d90 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffffe8ffffd09a50 RCX: ffffffff8a32076e RDX: 0000000000000002 RSI: ffffffff8d3ff7a0 RDI: ffffe8ffffd09a50 RBP: ffffffff8d3ff7a0 R08: 0000000000000001 R09: ffffed1017326d9d R10: ffff8880b9936ceb R11: 0000000000000000 R12: 0000000000000002 R13: ffffffff8d3ff888 R14: 0000000000000002 R15: 0000000000000000 cpuidle_enter_state+0x82/0x500 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:215 [inline] do_idle+0x315/0x3f0 kernel/sched/idle.c:282 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379 start_secondary+0x200/0x290 arch/x86/kernel/smpboot.c:326 secondary_startup_64_no_verify+0x167/0x16b CPU: 0 PID: 28470 Comm: kworker/0:2 Not tainted 6.5.0-rc2-syzkaller-00052-gbfa3037d8280 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:__sanitizer_cov_trace_pc+0x60/0x70 kernel/kcov.c:225 Code: 82 e0 15 00 00 83 f8 02 75 20 48 8b 8a e8 15 00 00 8b 92 e4 15 00 00 48 8b 01 48 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 f3 0f 1e fa 41 57 RSP: 0018:ffffc900150bf118 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 000000000000003f RCX: 0000000000000000 RDX: ffff888022be0000 RSI: ffffffff885984d1 RDI: 0000000000000006 RBP: ffff88801f5b9800 R08: 0000000000000006 R09: 000000000000003f R10: 0000000000000022 R11: 000000000000004e R12: 20d82bef93ea0041 R13: 0000000000000000 R14: dffffc0000000000 R15: 20d82bef93ea0080 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 0000000036d9e000 CR4: 00000000003526f0 Call Trace: find_entry_to_transmit+0x4d1/0x9f0 net/sched/sch_taprio.c:360 get_packet_txtime net/sched/sch_taprio.c:508 [inline] taprio_enqueue_one+0x881/0x1640 net/sched/sch_taprio.c:577 taprio_enqueue+0x239/0x7e0 net/sched/sch_taprio.c:658 dev_qdisc_enqueue+0x3f/0x230 net/core/dev.c:3732 __dev_xmit_skb net/core/dev.c:3821 [inline] __dev_queue_xmit+0x2202/0x3f20 net/core/dev.c:4169 dev_queue_xmit include/linux/netdevice.h:3088 [inline] neigh_resolve_output net/core/neighbour.c:1552 [inline] neigh_resolve_output+0x58c/0x900 net/core/neighbour.c:1532 neigh_output include/net/neighbour.h:544 [inline] ip6_finish_output2+0x5d0/0x1b20 net/ipv6/ip6_output.c:135 __ip6_finish_output net/ipv6/ip6_output.c:196 [inline] ip6_finish_output+0x485/0x11d0 net/ipv6/ip6_output.c:207 NF_HOOK_COND include/linux/netfilter.h:292 [inline] ip6_output+0x243/0x890 net/ipv6/ip6_output.c:228 dst_output include/net/dst.h:458 [inline] NF_HOOK.constprop.0+0xfd/0x540 include/linux/netfilter.h:303 ndisc_send_skb+0x9e8/0x1430 net/ipv6/ndisc.c:508 ndisc_send_ns+0xc7/0x140 net/ipv6/ndisc.c:666 addrconf_dad_work+0xca3/0x1410 net/ipv6/addrconf.c:4175 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597 worker_thread+0x687/0x1110 kernel/workqueue.c:2748 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296 RIP: 0000:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000