sched: DL replenish lagged too much
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15677/3:b..l P15675/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=54493, q=1252092 ncpus=2)
task:syz.6.2403 state:R running task stack:26536 pid:15675 tgid:15675 ppid:10266 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7234
irqentry_exit+0x17b/0x670 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x5e/0x380 kernel/locking/lockdep.c:5872
Code: 05 fb 70 28 12 83 f8 07 0f 87 f0 00 00 00 48 0f a3 05 c6 9b f4 0e 0f 82 c2 02 00 00 8b 35 de ce f4 0e 85 f6 0f 85 dd 00 00 00 <48> 8b 44 24 30 65 48 2b 05 9d 70 28 12 0f 85 02 03 00 00 48 83 c4
RSP: 0018:ffffc9000215f328 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8de4885a RDI: ffffffff8c1ae9a0
RBP: ffffffff8e7e93e0 R08: 0000000021944811 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
rcu_read_lock include/linux/rcupdate.h:850 [inline]
class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0xd1/0x1ea0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x162/0x1e0 mm/page_owner.c:165
__reset_page_owner+0x84/0x190 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1432 [inline]
__free_frozen_pages+0x7ca/0x10a0 mm/page_alloc.c:2977
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4501 [inline]
slab_alloc_node mm/slub.c:4830 [inline]
kmem_cache_alloc_noprof+0x241/0x6e0 mm/slub.c:4837
vm_area_dup+0x27/0x8e0 mm/vma_init.c:123
__split_vma+0x18c/0xd90 mm/vma.c:513
split_vma mm/vma.c:596 [inline]
vma_modify+0x1121/0x2250 mm/vma.c:1674
vma_modify_flags+0x257/0x3d0 mm/vma.c:1694
mprotect_fixup+0x209/0xb70 mm/mprotect.c:756
do_mprotect_pkey+0x9e1/0xe70 mm/mprotect.c:930
__do_sys_mprotect mm/mprotect.c:951 [inline]
__se_sys_mprotect mm/mprotect.c:948 [inline]
__x64_sys_mprotect+0x78/0xc0 mm/mprotect.c:948
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa9f3d9bd77
RSP: 002b:00007fffb4894198 EFLAGS: 00000206 ORIG_RAX: 000000000000000a
RAX: ffffffffffffffda RBX: 00007fa9f4c506c0 RCX: 00007fa9f3d9bd77
RDX: 0000000000000003 RSI: 0000000000020000 RDI: 00007fa9f4c31000
RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000021000 R11: 0000000000000206 R12: 00007fffb48942f0
R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000
task:syz.6.2403 state:R running task stack:27000 pid:15677 tgid:15675 ppid:10266 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7091
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__local_bh_enable_ip+0xff/0x120 kernel/softirq.c:457
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline]
__dev_queue_xmit+0x7f1/0x4750 net/core/dev.c:4856
dev_queue_xmit include/linux/netdevice.h:3384 [inline]
neigh_hh_output include/net/neighbour.h:540 [inline]
neigh_output include/net/neighbour.h:554 [inline]
ip_finish_output2+0xf4a/0x24d0 net/ipv4/ip_output.c:237
__ip_finish_output.part.0+0x444/0x6f0 net/ipv4/ip_output.c:315
__ip_finish_output net/ipv4/ip_output.c:303 [inline]
ip_finish_output net/ipv4/ip_output.c:325 [inline]
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip_output+0x39b/0xec0 net/ipv4/ip_output.c:438
dst_output include/net/dst.h:470 [inline]
ip_local_out net/ipv4/ip_output.c:131 [inline]
__ip_queue_xmit+0x1b73/0x22b0 net/ipv4/ip_output.c:534
__tcp_transmit_skb+0x3347/0x4b50 net/ipv4/tcp_output.c:1693
tcp_transmit_skb net/ipv4/tcp_output.c:1711 [inline]
tcp_send_syn_data net/ipv4/tcp_output.c:4287 [inline]
tcp_connect+0x2956/0x5630 net/ipv4/tcp_output.c:4376
tcp_v4_connect+0x158b/0x1bf0 net/ipv4/tcp_ipv4.c:347
__inet_stream_connect+0x208/0xfa0 net/ipv4/af_inet.c:679
tcp_sendmsg_fastopen+0x3ed/0x750 net/ipv4/tcp.c:1098
tcp_sendmsg_locked+0x279a/0x45f0 net/ipv4/tcp.c:1194
tcp_sendmsg+0x2e/0x50 net/ipv4/tcp.c:1464
inet_sendmsg+0xb9/0x140 net/ipv4/af_inet.c:859
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x467/0x520 net/socket.c:2206
__do_sys_sendto net/socket.c:2213 [inline]
__se_sys_sendto net/socket.c:2209 [inline]
__x64_sys_sendto+0xe0/0x1c0 net/socket.c:2209
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa9f3d9bf79
RSP: 002b:00007fa9f4c71028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fa9f4015fa0 RCX: 00007fa9f3d9bf79
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fa9f3e327e0 R08: 0000200000e68000 R09: 0000000000000010
R10: 00000000200007fd R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa9f4016038 R14: 00007fa9f4015fa0 R15: 00007fffb48941f8
rcu: rcu_preempt kthread starved for 3887 jiffies! g54493 f0x2 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:28680 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7004
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 15679 Comm: kworker/u8:4 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:__unwind_start+0x3c9/0x7f0 arch/x86/kernel/unwind_orc.c:773
Code: 24 08 85 d2 0f 84 2f ff ff ff 4d 89 fd 48 c1 e8 03 48 bd 00 00 00 00 00 fc ff df 49 c1 ed 03 49 89 c4 49 01 ed 49 01 ec eb 2a <4c> 89 f7 e8 7f dd ff ff 4c 89 f0 48 c1 e8 03 0f b6 04 28 84 c0 74
RSP: 0018:ffffc90000a08198 EFLAGS: 00000202
RAX: 1ffff92000141044 RBX: ffffc90000a08278 RCX: ffffc90000a08280
RDX: ffffc90000a09000 RSI: ffffffff8de6e909 RDI: ffffffff8c1ae9a0
RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000
R10: ffffc90000a081e8 R11: 0000000000000000 R12: fffff5200014103f
R13: fffff5200014103e R14: ffffc90000a081e8 R15: ffffc90000a081f0
FS: 0000000000000000(0000) GS:ffff88812444d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000400000 CR3: 000000002528d000 CR4: 00000000003526f0
Call Trace:
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0x73/0xf0 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
__call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3131
call_rcu_hurry include/linux/rcupdate.h:125 [inline]
dst_release net/core/dst.c:178 [inline]
dst_release+0x259/0x330 net/core/dst.c:166
refdst_drop include/net/dst.h:272 [inline]
skb_dst_drop include/net/dst.h:284 [inline]
skb_release_head_state+0x293/0x400 net/core/skbuff.c:1177
skb_release_all net/core/skbuff.c:1201 [inline]
__kfree_skb net/core/skbuff.c:1217 [inline]
consume_skb net/core/skbuff.c:1450 [inline]
consume_skb+0x8a/0x110 net/core/skbuff.c:1444
nft_synproxy_eval_v4 net/netfilter/nft_synproxy.c:61 [inline]
nft_synproxy_do_eval+0xa7b/0xd50 net/netfilter/nft_synproxy.c:142
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x2e8/0x1930 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0xee/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xbf/0x220 net/netfilter/core.c:623
nf_hook.constprop.0+0x2a6/0x750 include/linux/netfilter.h:273
NF_HOOK include/linux/netfilter.h:316 [inline]
ip_local_deliver+0x163/0x1f0 net/ipv4/ip_input.c:262
dst_input include/net/dst.h:480 [inline]
ip_rcv_finish net/ipv4/ip_input.c:453 [inline]
NF_HOOK include/linux/netfilter.h:318 [inline]
NF_HOOK include/linux/netfilter.h:312 [inline]
ip_rcv+0x2d9/0x5d0 net/ipv4/ip_input.c:573
__netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:6149
__netif_receive_skb+0x1f/0x120 net/core/dev.c:6262
process_backlog+0x37a/0x1580 net/core/dev.c:6614
__napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7678
napi_poll net/core/dev.c:7741 [inline]
net_rx_action+0xa40/0xf20 net/core/dev.c:7893
handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
do_softirq kernel/softirq.c:523 [inline]
do_softirq+0xac/0xe0 kernel/softirq.c:510
__local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:450
local_bh_enable include/linux/bottom_half.h:33 [inline]
__alloc_skb+0x5db/0x710 net/core/skbuff.c:697
alloc_skb include/linux/skbuff.h:1383 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline]
nsim_dev_trap_report_work+0x2af/0xd10 drivers/net/netdevsim/dev.c:922
process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275
process_scheduled_works kernel/workqueue.c:3358 [inline]
worker_thread+0x5da/0xe40 kernel/workqueue.c:3439
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245