rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P43/1:b..l P5571/1:b..l P18191/3:b..l
rcu: (detected by 1, t=10502 jiffies, g=122545, q=638 ncpus=2)
task:syz.4.3704 state:R running task stack:24968 pid:18191 tgid:18185 ppid:15335 task_flags:0x400040 flags:0x10080003
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7113
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7137
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+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
filemap_map_pages+0x179f/0x1e20 mm/filemap.c:3870
do_fault_around mm/memory.c:5674 [inline]
do_read_fault mm/memory.c:5707 [inline]
do_fault mm/memory.c:5850 [inline]
do_pte_missing mm/memory.c:4362 [inline]
handle_pte_fault mm/memory.c:6195 [inline]
__handle_mm_fault+0x347e/0x5400 mm/memory.c:6336
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6505
do_user_addr_fault+0x764/0x1380 arch/x86/mm/fault.c:1387
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0010:rep_movs_alternative+0x30/0x90 arch/x86/lib/copy_user_64.S:60
Code: 83 f9 08 73 25 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 <48> 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 db 83 f9 08
RSP: 0018:ffffc9000e9978d8 EFLAGS: 00050206
RAX: 00007ffffffff001 RBX: 000000000000001c RCX: 000000000000001c
RDX: 0000000000000001 RSI: 00000000800d5000 RDI: ffffc9000e997960
RBP: ffffc9000e9979f0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52001d32f2f R12: ffffc9000e997960
R13: ffffc9000e997ca0 R14: ffffc9000e997960 R15: 00000000800d5000
copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline]
_inline_copy_from_user include/linux/uaccess.h:178 [inline]
_copy_from_user+0x7a/0xb0 lib/usercopy.c:18
copy_from_user include/linux/uaccess.h:212 [inline]
get_compat_msghdr+0xad/0x4a0 net/compat.c:91
recvmsg_copy_msghdr net/socket.c:2814 [inline]
___sys_recvmsg+0x17f/0x510 net/socket.c:2888
do_recvmmsg+0x36a/0x770 net/socket.c:2979
__sys_recvmmsg+0x19d/0x280 net/socket.c:3061
__do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline]
__se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline]
__ia32_compat_sys_recvmmsg_time32+0xbf/0xe0 net/compat.c:414
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306
do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f55539
RSP: 002b:00000000f540455c EFLAGS: 00000206 ORIG_RAX: 0000000000000151
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000800000c0
RDX: 0000000000010106 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
task:crond state:R running task stack:23720 pid:5571 tgid:5571 ppid:1 task_flags:0x400000 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x9/0x3e0 kernel/locking/lockdep.c:5876
Code: 24 e9 08 fa ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 <41> 55 41 54 53 48 83 ec 30 49 89 f5 49 89 fe 65 48 8b 05 80 ed d0
RSP: 0018:ffffc90003aaf718 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff90183d01 RCX: 9268bde91f402c00
RDX: ffffc90003aaf801 RSI: ffffffff81738c45 RDI: ffffffff8df3d6e0
RBP: dffffc0000000000 R08: ffffc90003aafc80 R09: 0000000000000000
R10: ffffc90003aaf858 R11: fffff52000755f0d R12: ffffc90003aafc90
R13: ffffc90003aa8000 R14: ffffc90003aaf808 R15: ffffffff81738c45
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
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:156
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:311
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1394 [inline]
__free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2901
discard_slab mm/slub.c:3330 [inline]
__put_partials+0x146/0x170 mm/slub.c:3876
put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3951
__slab_free+0x2b9/0x390 mm/slub.c:5929
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4978 [inline]
slab_alloc_node mm/slub.c:5288 [inline]
kmem_cache_alloc_noprof+0x367/0x6e0 mm/slub.c:5295
getname_flags+0xb8/0x540 fs/namei.c:146
getname include/linux/fs.h:2924 [inline]
do_sys_openat2+0xbc/0x1c0 fs/open.c:1431
do_sys_open fs/open.c:1452 [inline]
__do_sys_openat fs/open.c:1468 [inline]
__se_sys_openat fs/open.c:1463 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1463
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd1cf968407
RSP: 002b:00007fffb2650c30 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fd1cf818c80 RCX: 00007fd1cf968407
RDX: 0000000000000000 RSI: 00007fd1cfb5b764 RDI: ffffffffffffff9c
RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007fd1cfb67492
R13: 00007fd1cfb67492 R14: 0000000000000001 R15: 000000000000002c
task:kworker/1:1 state:R running task stack:21896 pid:43 tgid:43 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: 0x0 (wg-crypt-wg2)
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_notrace+0xd1/0x110 kernel/sched/core.c:7206
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+0x1965/0x2390 arch/x86/kernel/unwind_orc.c:680
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:156
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:311
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1394 [inline]
__free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2901
discard_slab mm/slub.c:3330 [inline]
__put_partials+0x146/0x170 mm/slub.c:3876
put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3951
__slab_free+0x2b9/0x390 mm/slub.c:5929
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4978 [inline]
slab_alloc_node mm/slub.c:5288 [inline]
__kmalloc_cache_noprof+0x36f/0x6f0 mm/slub.c:5766
kmalloc_noprof include/linux/slab.h:957 [inline]
__kthread_create_on_node+0xef/0x3e0 kernel/kthread.c:510
kthread_create_on_node+0xdd/0x130 kernel/kthread.c:587
create_worker+0x299/0x720 kernel/workqueue.c:2802
maybe_create_worker kernel/workqueue.c:3063 [inline]
manage_workers kernel/workqueue.c:3140 [inline]
worker_thread+0x33e/0xda0 kernel/workqueue.c:3402
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 9235 jiffies! g122545 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:27224 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
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+0x4bc/0x870 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:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:debug_lockdep_rcu_enabled+0x2d/0x40 kernel/rcu/update.c:320
Code: fa 31 c0 83 3d a7 66 36 04 00 74 1e 83 3d aa 95 36 04 00 74 15 65 48 8b 0c 25 08 50 6e 92 31 c0 83 b9 2c 0b 00 00 00 0f 94 c0 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90
RSP: 0018:ffffc90000a07bc8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffff897baf53 RCX: ffff88801ce9dac0
RDX: 0000000000000100 RSI: ffffffff8bbf08c0 RDI: ffffffff8bbf0880
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff897baf53
R10: 0000000000000003 R11: ffffffff897c02c0 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff888029f0a800 R15: 0000000000000031
FS: 0000000000000000(0000) GS:ffff88812623b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000800cd000 CR3: 000000005e49c000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
net_generic include/net/netns/generic.h:46 [inline]
synproxy_pernet+0xec/0x240 include/net/netfilter/nf_synproxy.h:32
ipv6_synproxy_hook+0xa9/0xda0 net/netfilter/nf_synproxy_core.c:1060
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
nf_hook+0x217/0x380 include/linux/netfilter.h:273
NF_HOOK_COND include/linux/netfilter.h:306 [inline]
ip6_output+0x30b/0x550 net/ipv6/ip6_output.c:247
synproxy_send_tcp_ipv6+0x543/0x700 net/netfilter/nf_synproxy_core.c:851
synproxy_send_client_synack_ipv6+0x80e/0xca0 net/netfilter/nf_synproxy_core.c:897
nft_synproxy_eval_v6+0x36e/0x560 net/netfilter/nft_synproxy.c:90
nft_synproxy_do_eval+0x3d7/0x570 net/netfilter/nft_synproxy.c:145
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
ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:500
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6079 [inline]
__netif_receive_skb+0xd3/0x380 net/core/dev.c:6192
process_backlog+0x60e/0x14f0 net/core/dev.c:6544
__napi_poll+0xc7/0x360 net/core/dev.c:7594
napi_poll net/core/dev.c:7657 [inline]
net_rx_action+0x5f7/0xdf0 net/core/dev.c:7784
handle_softirqs+0x286/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc 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 93 b1 21 00 f3 0f 1e fa fb f4 c8 e6 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6
RAX: cb339ef5b57acc00 RBX: ffffffff81967b47 RCX: cb339ef5b57acc00
RDX: 0000000000000001 RSI: ffffffff8d70e43a RDI: ffffffff8bbf08e0
RBP: ffffc90000197f10 R08: ffff8880b8932fdb R09: 1ffff110171265fb
R10: dffffc0000000000 R11: ffffed10171265fc R12: ffffffff8f7cee70
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110039d3b58
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e7/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x147