rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 GPs behind) idle=0c44/1/0x4000000000000000 softirq=184327/184329 fqs=1490
rcu: 	(t=10502 jiffies g=208361 q=4133 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 7522 jiffies! g208361 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=74361
rcu: rcu_preempt kthread starved for 7525 jiffies! g208361 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:27608 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: 5c 80 02 e9 13 05 03 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 53 3a 1a 00 fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc90000007468 EFLAGS: 00000246
RAX: ffffffff8176219a RBX: 0000000000000003 RCX: ffffffff8e88ef40
RDX: 0000000000000100 RSI: ffffffff8e22a902 RDI: ffffffff8c4bd380
RBP: 0000000000000003 R08: ffffffff905777f7 R09: 1ffffffff20aeefe
R10: dffffc0000000000 R11: fffffbfff20aeeff R12: 0000000000000200
R13: 0000000000000000 R14: ffff88808500a158 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888124f57000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc0e8a7f52 CR3: 0000000036e70000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
 kvm_wait+0x10f/0x150 arch/x86/kernel/kvm.c:1096
 pv_wait arch/x86/include/asm/paravirt-spinlock.h:83 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:466 [inline]
 __pv_queued_spin_lock_slowpath+0x74a/0xbc0 kernel/locking/qspinlock.c:325
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt-spinlock.h:35 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/paravirt-spinlock.h:66 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x26c/0x2f0 kernel/locking/spinlock_debug.c:116
 spin_lock include/linux/spinlock.h:342 [inline]
 __dev_xmit_skb net/core/dev.c:4252 [inline]
 __dev_queue_xmit+0xd56/0x3820 net/core/dev.c:4836
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip6_output+0x337/0x540 net/ipv6/ip6_output.c:246
 dst_output include/net/dst.h:471 [inline]
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ndisc_send_skb+0xcb2/0x1650 net/ipv6/ndisc.c:512
 addrconf_rs_timer+0x2d2/0x6c0 net/ipv6/addrconf.c:4072
 call_timer_fn+0x192/0x5e0 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2374 [inline]
 __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386
 run_timer_base kernel/time/timer.c:2395 [inline]
 run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405
 handle_softirqs+0x225/0x840 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: 5c 80 02 e9 13 05 03 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 53 3a 1a 00 fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffffff8e807de0 EFLAGS: 00000246
RAX: 000000000025295f RBX: ffffffff819ab33c RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8e22a902 RDI: ffffffff8c4bd380
RBP: ffffffff8e807eb8 R08: ffff8880b86338db R09: 1ffff110170c671b
R10: dffffc0000000000 R11: ffffed10170c671c R12: 0000000000000000
R13: 1ffffffff1d11de8 R14: 1ffffffff1d00fc4 R15: dffffc0000000000
 arch_safe_halt arch/x86/kernel/process.c:767 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:768
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x1cc/0x540 kernel/sched/idle.c:355
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454
 rest_init+0x2de/0x300 init/main.c:717
 start_kernel+0x392/0x3e0 init/main.c:1175
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x137/0x1b0 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x157
 </TASK>
CPU: 1 UID: 0 PID: 8156 Comm: syz.1.9339 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:rcu_rnp_online_cpus kernel/rcu/tree.c:4026 [inline]
RIP: 0010:rcu_rdp_cpu_online kernel/rcu/tree.c:4036 [inline]
RIP: 0010:rcu_lockdep_current_cpu_online+0xbf/0x120 kernel/rcu/tree.c:4077
Code: 20 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 d4 6a 88 00 48 8b 1b 48 83 c3 70 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 b7 6a 88 00 4c 85 3b 75 1a 48 c7 c7 00 01 b6 8e
RSP: 0018:ffffc9000427f4f0 EFLAGS: 00000246
RAX: 1ffffffff1d6bf0e RBX: ffffffff8eb5f870 RCX: 0000000000000202
RDX: ffff8880236f1f00 RSI: ffffffff8c4bd360 RDI: ffff8880b873c1a8
RBP: ffffc9000427f610 R08: ffff8880236f1f00 R09: 0000000000000004
R10: 0000000000000008 R11: 0000000000000002 R12: ffff88808500a000
R13: ffff88808500a290 R14: dffffc0000000000 R15: 0000000000000002
FS:  00007fcae4c4d6c0(0000) GS:ffff888125057000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000f000 CR3: 00000000578e6000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 rcu_read_lock_held_common kernel/rcu/update.c:113 [inline]
 rcu_read_lock_bh_held+0x23/0x50 kernel/rcu/update.c:374
 hfsc_classify net/sched/sch_hfsc.c:1171 [inline]
 hfsc_enqueue+0x557/0xf50 net/sched/sch_hfsc.c:1545
 dev_qdisc_enqueue+0x4e/0x260 net/core/dev.c:4179
 __dev_xmit_skb net/core/dev.c:4294 [inline]
 __dev_queue_xmit+0x1b45/0x3820 net/core/dev.c:4836
 packet_snd net/packet/af_packet.c:3082 [inline]
 packet_sendmsg+0x3d95/0x5040 net/packet/af_packet.c:3114
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcae3d9de99
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcae4c4d028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fcae4025fa0 RCX: 00007fcae3d9de99
RDX: 000000000000fd1e RSI: 00002000000002c0 RDI: 0000000000000004
RBP: 00007fcae3e33eaf R08: 0000200000000140 R09: 0000000000000014
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcae4026038 R14: 00007fcae4025fa0 R15: 00007ffec86d2ac8
 </TASK>
sched: DL replenish lagged too much