rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5828/1:b..l P9175/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=33001, q=1160 ncpus=2)
task:syz.0.592 state:R running task stack:26648 pid:9175 tgid:9174 ppid:5827 task_flags:0x40044c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7193
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:895 [inline]
RIP: 0010:percpu_ref_put_many include/linux/percpu-refcount.h:337 [inline]
RIP: 0010:percpu_ref_put include/linux/percpu-refcount.h:351 [inline]
RIP: 0010:css_put include/linux/cgroup_refcnt.h:79 [inline]
RIP: 0010:mem_cgroup_put+0x171/0x2a0 include/linux/memcontrol.h:809
Code: 00 00 00 e8 01 b0 c0 ff 65 49 ff 0c 24 e8 f7 af 5c 09 89 c5 31 ff 89 c6 e8 2c b4 c0 ff 85 ed 74 10 e8 13 8f a6 ff 84 c0 74 0e da af c0 ff eb 56 e8 d3 af c0 ff eb 4f e8 cc af 5c 09 89 c5 31
RSP: 0018:ffffc9000b83f918 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff82010770 RCX: 98f39fc10c310600
RDX: ffff88802b160000 RSI: ffffffff8be07940 RDI: ffffffff8be07900
RBP: 0000000000000001 R08: ffffffff82010770 R09: ffffffff8e13f2e0
R10: dffffc0000000000 R11: ffffed100385b47d R12: 0000607eda051af0
R13: dffffc0000000000 R14: ffff88801c2d9a80 R15: ffff88801c2d9a90
lru_gen_del_mm+0x4e3/0x550 mm/vmscan.c:2958
__mmput+0x385/0x430 kernel/fork.c:1187
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x850/0x25b0 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4a7518f34b
RSP: 002b:00007f4a760c2f10 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 00007f4a7518f34b
RDX: 00007f4a760c3fe0 RSI: 0000000080085502 RDI: 0000000000000003
RBP: 00007f4a760c3fe0 R08: 0000000000000000 R09: 00302e6364755f79
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502
R13: 0000000800000000 R14: 00002000000001c0 R15: 00007f4a7521f52a
task:syz-executor state:R running task stack:18256 pid:5828 tgid:5828 ppid:5822 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
preempt_schedule_notrace+0xd1/0x110 kernel/sched/core.c:7143
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:752
rcu_read_unlock include/linux/rcupdate.h:895 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x1a6d/0x23d0 arch/x86/kernel/unwind_orc.c:695
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1406 [inline]
__free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2943
discard_slab mm/slub.c:3346 [inline]
__put_partials+0x146/0x170 mm/slub.c:3886
put_cpu_partial+0x1f2/0x2d0 mm/slub.c:3961
__slab_free+0x288/0x2a0 mm/slub.c:5956
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5267 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5274
anon_vma_alloc mm/rmap.c:93 [inline]
anon_vma_fork+0xde/0x500 mm/rmap.c:359
dup_mmap+0x954/0x1b80 mm/mmap.c:1790
dup_mm kernel/fork.c:1533 [inline]
copy_mm+0x14f/0x770 kernel/fork.c:1585
copy_process+0x165d/0x3950 kernel/fork.c:2225
kernel_clone+0x21e/0x820 kernel/fork.c:2655
__do_sys_clone kernel/fork.c:2796 [inline]
__se_sys_clone kernel/fork.c:2780 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2780
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0774785e93
RSP: 002b:00007ffdd95d66c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0774785e93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055559381d7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 0000000000043b6e R15: 00007ffdd95d6860
rcu: rcu_preempt kthread starved for 1805 jiffies! g33001 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:27200 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
__schedule_loop kernel/sched/core.c:6948 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6963
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
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: 9211 Comm: kworker/u8:36 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: bat_events batadv_tt_purge
RIP: 0010:fib_table_lookup+0x165/0x16e0 net/ipv4/fib_trie.c:1448
Code: 02 00 00 45 8b 2c 24 45 31 fd 49 8d 5c 24 04 48 89 d8 48 c1 e8 03 48 89 44 24 18 0f b6 04 28 84 c0 0f 85 17 02 00 00 0f b6 2b 20 00 00 00 89 ee e8 5f 6b dd f7 83 fd 1f 4c 89 74 24 30 0f 87
RSP: 0018:ffffc90000a07cd0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88802fd3cb24 RCX: ffff888035b71e80
RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 000000000000001e R08: ffffc90000a07eaf R09: 0000000000000000
R10: ffffc90000a07e80 R11: fffff52000140fd6 R12: ffff88802fd3cb20
R13: 000000007f000001 R14: ffff88801e724630 R15: 000000007f000001
FS: 0000000000000000(0000) GS:ffff888125d25000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f39a0e94ff8 CR3: 000000007f756000 CR4: 00000000003526f0
Call Trace:
__inet_dev_addr_type+0x2a2/0x4b0 net/ipv4/fib_frontend.c:226
ip_route_me_harder+0x3db/0xf10 net/ipv4/netfilter.c:36
synproxy_send_tcp+0x3a7/0x700 net/netfilter/nf_synproxy_core.c:431
synproxy_send_client_synack+0x8bb/0xe20 net/netfilter/nf_synproxy_core.c:484
nft_synproxy_eval_v4+0x36e/0x560 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x345/0x570 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x40c/0x1920 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:273 [inline]
NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6138 [inline]
__netif_receive_skb+0x143/0x380 net/core/dev.c:6251
process_backlog+0x622/0x1500 net/core/dev.c:6603
__napi_poll+0xae/0x320 net/core/dev.c:7667
napi_poll net/core/dev.c:7730 [inline]
net_rx_action+0x672/0xe50 net/core/dev.c:7882
handle_softirqs+0x27d/0x850 kernel/softirq.c:626
do_softirq+0xec/0x180 kernel/softirq.c:523
__local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:450
spin_unlock_bh include/linux/spinlock.h:396 [inline]
batadv_tt_global_purge net/batman-adv/translation-table.c:2250 [inline]
batadv_tt_purge+0x4d1/0x9e0 net/batman-adv/translation-table.c:3510
process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246