rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5843/1:b..l P5820/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=20365, q=2880 ncpus=2)
task:syz-executor state:R running task stack:25512 pid:5820 tgid:5820 ppid:5815 task_flags:0x40050c flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5401 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6790
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6970
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
zap_pte_range mm/memory.c:1765 [inline]
zap_pmd_range mm/memory.c:1827 [inline]
zap_pud_range mm/memory.c:1856 [inline]
zap_p4d_range mm/memory.c:1877 [inline]
unmap_page_range+0x106b/0x4350 mm/memory.c:1898
unmap_single_vma.constprop.0+0x153/0x240 mm/memory.c:1941
unmap_vmas+0x218/0x470 mm/memory.c:1985
exit_mmap+0x1b9/0xb90 mm/mmap.c:1284
__mmput+0x12a/0x410 kernel/fork.c:1121
mmput+0x62/0x70 kernel/fork.c:1144
exit_mm kernel/exit.c:581 [inline]
do_exit+0x7c4/0x2bd0 kernel/exit.c:952
do_group_exit+0xd3/0x2a0 kernel/exit.c:1105
get_signal+0x2673/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2af0784b53
RSP: 002b:00007ffc587c3c28 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 00000000000016c1 RCX: 00007f2af0784b53
RDX: 0000000040000000 RSI: 00007ffc587c3c3c RDI: 00000000ffffffff
RBP: 00007ffc587c3c3c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
task:udevd state:R running task stack:24664 pid:5843 tgid:5843 ppid:5202 task_flags:0x40014c flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5401 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6790
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7113
irqentry_exit+0x36/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x183/0x2f0 kernel/locking/lockdep.c:5896
Code: 0f c1 05 78 58 38 12 83 f8 01 0f 85 1d 01 00 00 9c 58 f6 c4 02 0f 85 08 01 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 8d 16 38 12 0f 85 58 01 00 00 48 83 c4 18 5b 41 5c 41
RSP: 0018:ffffc90003c0f410 EFLAGS: 00000206
RAX: 185db9d399a7e800 RBX: ffffffff8e5c4e80 RCX: ffffc90003c0f41c
RDX: 0000000000000001 RSI: ffffffff8de0d05d RDI: ffffffff8c158f60
RBP: 00007fad224f16c5 R08: 328b0d0cf36cb5da R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff81a6cb74
R13: 0000000000000206 R14: ffff88801dbf4880 R15: 0000000000000002
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
is_module_text_address+0x149/0x230 kernel/module/main.c:3822
kernel_text_address kernel/extable.c:119 [inline]
kernel_text_address+0x81/0x100 kernel/extable.c:94
__kernel_text_address+0xd/0x40 kernel/extable.c:79
unwind_get_return_address+0x59/0xa0 arch/x86/kernel/unwind_orc.c:369
arch_stack_walk+0xa6/0x100 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1248 [inline]
free_unref_folios+0xa65/0x1800 mm/page_alloc.c:2763
folios_put_refs+0x56f/0x740 mm/swap.c:992
free_pages_and_swap_cache+0x245/0x4a0 mm/swap_state.c:264
__tlb_batch_free_encoded_pages+0xf9/0x290 mm/mmu_gather.c:136
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu mm/mmu_gather.c:404 [inline]
tlb_finish_mmu+0x168/0x7c0 mm/mmu_gather.c:497
exit_mmap+0x403/0xb90 mm/mmap.c:1297
__mmput+0x12a/0x410 kernel/fork.c:1121
mmput+0x62/0x70 kernel/fork.c:1144
exit_mm kernel/exit.c:581 [inline]
do_exit+0x7c4/0x2bd0 kernel/exit.c:952
do_group_exit+0xd3/0x2a0 kernel/exit.c:1105
__do_sys_exit_group kernel/exit.c:1116 [inline]
__se_sys_exit_group kernel/exit.c:1114 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1114
x64_sys_call+0x1530/0x1730 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fad224f16c5
RSP: 002b:00007ffc4be27bd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000557567543240 RCX: 00007fad224f16c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 00005575672f52c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc4be27c20 R14: 0000000000000000 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 5881 jiffies! g20365 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:28872 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5401 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6790
__schedule_loop kernel/sched/core.c:6868 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6883
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:debug_lockdep_rcu_enabled+0x20/0x40 kernel/rcu/update.c:320
Code: 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 8b 05 86 5e 21 05 85 c0 74 20 8b 05 80 8f 21 05 85 c0 74 16 65 48 8b 05 48 7e 48 08 <8b> 80 ec 0a 00 00 85 c0 0f 94 c0 0f b6 c0 e9 7d f1 02 00 66 2e 0f
RSP: 0018:ffffc90000a08048 EFLAGS: 00000202
RAX: ffff88801e2e2440 RBX: 0000000000000002 RCX: 000000007938eb5a
RDX: 0000000000000000 RSI: ffffffff8de0d05d RDI: ffffffff8c158f60
RBP: ffffc90000a08160 R08: 39529a686290c103 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: fffff52000141025
R13: ffffc90000a08118 R14: ffffc90000a08118 R15: ffffc90000a08120
FS: 0000000000000000(0000) GS:ffff888124816000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd0f7215efc CR3: 000000005d5d9000 CR4: 00000000003526f0
Call Trace:
rcu_read_lock include/linux/rcupdate.h:842 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xd6/0x20a0 arch/x86/kernel/unwind_orc.c:479
__unwind_start+0x45f/0x7f0 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0x73/0x100 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2381 [inline]
slab_free mm/slub.c:4643 [inline]
kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4745
skb_kfree_head net/core/skbuff.c:1046 [inline]
skb_kfree_head net/core/skbuff.c:1043 [inline]
skb_free_head+0x1b7/0x210 net/core/skbuff.c:1060
skb_release_data+0x776/0x9c0 net/core/skbuff.c:1087
skb_release_all net/core/skbuff.c:1152 [inline]
__kfree_skb net/core/skbuff.c:1166 [inline]
consume_skb net/core/skbuff.c:1398 [inline]
consume_skb+0xbf/0x100 net/core/skbuff.c:1392
nft_synproxy_eval_v4 net/netfilter/nft_synproxy.c:60 [inline]
nft_synproxy_do_eval+0xa6b/0xd80 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x2e9/0x1920 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x18a/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623
nf_hook.constprop.0+0x422/0x750 include/linux/netfilter.h:272
NF_HOOK include/linux/netfilter.h:315 [inline]
ip_local_deliver+0x169/0x1f0 net/ipv4/ip_input.c:254
dst_input include/net/dst.h:469 [inline]
ip_rcv_finish net/ipv4/ip_input.c:448 [inline]
NF_HOOK include/linux/netfilter.h:317 [inline]
NF_HOOK include/linux/netfilter.h:311 [inline]
ip_rcv+0x2c3/0x5d0 net/ipv4/ip_input.c:568
__netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:5977
__netif_receive_skb+0x1d/0x160 net/core/dev.c:6090
process_backlog+0x442/0x15e0 net/core/dev.c:6442
__napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7414
napi_poll net/core/dev.c:7478 [inline]
net_rx_action+0xa9f/0xfe0 net/core/dev.c:7605
handle_softirqs+0x219/0x8e0 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: fb 6b 02 c3 cc cc cc cc 0f 1f 00 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 03 e9 21 00 fb f4 7c fb 02 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df8 EFLAGS: 000002c2
RAX: 0000000003690205 RBX: 0000000000000001 RCX: ffffffff8b882c79
RDX: 0000000000000000 RSI: ffffffff8de3251e RDI: ffffffff8c158f60
RBP: ffffed1003c5c488 R08: 0000000000000001 R09: ffffed10170a6645
R10: ffff8880b853322b R11: 0000000000000001 R12: 0000000000000001
R13: ffff88801e2e2440 R14: ffffffff90a97f50 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:749
default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117
cpuidle_idle_call kernel/sched/idle.c:185 [inline]
do_idle+0x391/0x510 kernel/sched/idle.c:325
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423
start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x148