syzbot

sched: DL replenish lagged too much
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=30002 jiffies, g=278801, q=94 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 30002 (4295523060-4295493058), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 30002 jiffies! g278801 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:0     pid:17    tgid:17    ppid:2      flags:0x00000008
Call trace:
 __switch_to+0xf4/0x168 arch/arm64/kernel/process.c:606
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x330/0x8f8 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0x34/0x104 kernel/sched/core.c:6782
 schedule_timeout+0x80/0xf4 kernel/time/timer.c:2615
 rcu_gp_fqs_loop+0x138/0x48c kernel/rcu/tree.c:2045
 rcu_gp_kthread+0x130/0x15c kernel/rcu/tree.c:2247
 kthread+0x114/0x118 kernel/kthread.c:389
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Tainted: G    B              6.12.0-rc4-syzkaller-00047-gc2ee9f594da8 #0
Tainted: [B]=BAD_PAGE
Hardware name: linux,dummy-virt (DT)
pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : in_irqentry_text kernel/stacktrace.c:381 [inline]
pc : filter_irq_stacks+0x38/0x74 kernel/stacktrace.c:397
lr : stack_depot_save_flags+0x2c/0x5c4 lib/stackdepot.c:609
sp : ffff800080003250
x29: ffff800080003250 x28: 000000000100007f x27: fbf000000304fa00
x26: 0000000000000001 x25: ffff800082720000 x24: 0000000000000000
x23: fcf000000911b000 x22: 0000000000000001 x21: 0000000000000820
x20: ffff8000800032f0 x19: 0000000000000003 x18: 0000000000000001
x17: f9f0000007234070 x16: ffff800080000000 x15: faf00000290a4840
x14: 0000000000000004 x13: 0000000000000021 x12: 0000000000004788
x11: faf00000290a4b10 x10: faf00000290a4810 x9 : 0000000000000000
x8 : 0000000000000029 x7 : ffff8000800104f0 x6 : ffff8000800104f0
x5 : ffff800080010000 x4 : ffff800080010510 x3 : ffff800081575fe4
x2 : 0000000000000005 x1 : 0000000000000029 x0 : ffff8000800032f0
Call trace:
 in_irqentry_text kernel/stacktrace.c:379 [inline]
 filter_irq_stacks+0x38/0x74 kernel/stacktrace.c:397
 kasan_save_stack+0x50/0x64 mm/kasan/common.c:48
 save_stack_info+0x40/0x158 mm/kasan/tags.c:106
 kasan_save_alloc_info+0x14/0x20 mm/kasan/tags.c:142
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 unpoison_slab_object mm/kasan/common.c:308 [inline]
 __kasan_slab_alloc+0x94/0xcc mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:247 [inline]
 slab_post_alloc_hook mm/slub.c:4085 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 kmem_cache_alloc_noprof+0x10c/0x2c4 mm/slub.c:4141
 skb_clone+0x60/0xc4 net/core/skbuff.c:2084
 netem_enqueue+0x554/0xa90 net/sched/sch_netem.c:485
 dev_qdisc_enqueue net/core/dev.c:3787 [inline]
 __dev_xmit_skb net/core/dev.c:3883 [inline]
 __dev_queue_xmit+0x3dc/0xf24 net/core/dev.c:4394
 dev_queue_xmit include/linux/netdevice.h:3094 [inline]
 neigh_hh_output include/net/neighbour.h:526 [inline]
 neigh_output include/net/neighbour.h:540 [inline]
 ip_finish_output2+0x3c0/0x65c net/ipv4/ip_output.c:236
 __ip_finish_output net/ipv4/ip_output.c:314 [inline]
 __ip_finish_output+0xa4/0x1a0 net/ipv4/ip_output.c:296
 ip_finish_output+0x34/0x10c net/ipv4/ip_output.c:324
 NF_HOOK_COND include/linux/netfilter.h:303 [inline]
 ip_output+0x68/0x100 net/ipv4/ip_output.c:434
 dst_output include/net/dst.h:450 [inline]
 ip_local_out+0x48/0x5c net/ipv4/ip_output.c:130
 synproxy_send_tcp.isra.0+0x108/0x180 net/netfilter/nf_synproxy_core.c:439
 synproxy_send_client_synack+0x1b0/0x200 net/netfilter/nf_synproxy_core.c:484
 nft_synproxy_eval_v4 net/netfilter/nft_synproxy.c:59 [inline]
 nft_synproxy_do_eval+0x268/0x270 net/netfilter/nft_synproxy.c:141
 nft_synproxy_eval+0x14/0x38 net/netfilter/nft_synproxy.c:247
 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
 nft_do_chain+0x108/0x484 net/netfilter/nf_tables_core.c:288
 nft_do_chain_inet+0xa0/0x114 net/netfilter/nft_chain_filter.c:161
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0x48/0x118 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:269 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 ip_local_deliver+0xec/0x120 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:460 [inline]
 ip_rcv_finish+0x90/0xb0 net/ipv4/ip_input.c:449
 NF_HOOK include/linux/netfilter.h:314 [inline]
 NF_HOOK include/linux/netfilter.h:308 [inline]
 ip_rcv+0xec/0xf8 net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core+0x58/0x84 net/core/dev.c:5666
 __netif_receive_skb+0x18/0x60 net/core/dev.c:5779
 process_backlog+0x84/0x13c net/core/dev.c:6111
 __napi_poll+0x38/0x198 net/core/dev.c:6775
 napi_poll net/core/dev.c:6844 [inline]
 net_rx_action+0x344/0x3c8 net/core/dev.c:6966
 handle_softirqs+0x108/0x240 kernel/softirq.c:554
 __do_softirq+0x14/0x20 kernel/softirq.c:588
 ____do_softirq+0x10/0x1c arch/arm64/kernel/irq.c:81
 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:889
 do_softirq_own_stack+0x1c/0x28 arch/arm64/kernel/irq.c:86
 invoke_softirq kernel/softirq.c:435 [inline]
 __irq_exit_rcu kernel/softirq.c:637 [inline]
 irq_exit_rcu+0x8c/0xc4 kernel/softirq.c:649
 __el1_irq arch/arm64/kernel/entry-common.c:537 [inline]
 el1_interrupt+0x38/0x64 arch/arm64/kernel/entry-common.c:551
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:556
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:594
 __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:26 [inline]
 arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline]
 ksoftirqd_run_end kernel/softirq.c:411 [inline]
 run_ksoftirqd kernel/softirq.c:928 [inline]
 run_ksoftirqd+0x40/0x4c kernel/softirq.c:919
 smpboot_thread_fn+0x208/0x22c kernel/smpboot.c:164
 kthread+0x114/0x118 kernel/kthread.c:389
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860