rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P14465/1:b..l P5211/1:b..l P13448/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=54869, q=835319 ncpus=2)
task:syz-executor state:R running task stack:21768 pid:13448 tgid:13448 ppid:13426 task_flags:0x400140 flags:0x00080000
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:702
RIP: 0010:rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
RIP: 0010:rcu_read_lock include/linux/rcupdate.h:841 [inline]
RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1169 [inline]
RIP: 0010:unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
Code: 00 e8 c2 76 33 00 4c 8d 3d 00 00 00 00 48 c7 c7 60 b1 d3 8d 31 f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 41 57 e8 6e c2 29 00 <48> 83 c4 08 e8 15 77 c2 09 85 c0 74 3a e8 fc bc 32 00 84 c0 75 31
RSP: 0018:ffffc90003c2f7b0 EFLAGS: 00000286
RAX: ffc425970f709100 RBX: ffffffff82243527 RCX: ffc425970f709100
RDX: 0000000000000000 RSI: ffffffff8d6f525f RDI: ffffffff8b9eea60
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff81725d45
R10: ffffc90003c2f8d8 R11: ffffffff81aaf950 R12: 1ffff92000785f11
R13: ffffc90003c2f8c0 R14: ffffc90003c2f888 R15: ffffffff81725d45
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:308
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:2906
discard_slab mm/slub.c:3301 [inline]
__put_partials+0x146/0x170 mm/slub.c:3848
put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3923
__slab_free+0x2b9/0x390 mm/slub.c:5882
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:4946 [inline]
slab_alloc_node mm/slub.c:5245 [inline]
kmem_cache_alloc_lru_noprof+0x35d/0x6d0 mm/slub.c:5264
sock_alloc_inode+0x28/0xc0 net/socket.c:322
alloc_inode+0x67/0x1b0 fs/inode.c:346
new_inode_pseudo include/linux/fs.h:3394 [inline]
sock_alloc net/socket.c:637 [inline]
__sock_create+0x12d/0x9f0 net/socket.c:1569
sock_create net/socket.c:1663 [inline]
__sys_socket_create net/socket.c:1700 [inline]
__sys_socket+0xd7/0x1b0 net/socket.c:1747
__do_sys_socket net/socket.c:1761 [inline]
__se_sys_socket net/socket.c:1759 [inline]
__x64_sys_socket+0x7a/0x90 net/socket.c:1759
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fec4c990de7
RSP: 002b:00007fec4cd0f6f8 EFLAGS: 00000206 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fec4c990de7
RDX: 0000000000000006 RSI: 0000000000000001 RDI: 0000000000000002
RBP: 00007fec4cd0fdec R08: 0000000000000000 R09: 00007fec4cd0faf7
R10: 0000000000000000 R11: 0000000000000206 R12: 000000000000002c
R13: 0000000000000058 R14: 00000000000922d3 R15: 00007fec4cd0fe40
task:udevd state:R running task stack:22824 pid:5211 tgid:5211 ppid:1 task_flags:0x400140 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:702
RIP: 0010:kasan_check_range+0x5/0x2c0 mm/kasan/generic.c:199
Code: eb ec 90 0f 0b 90 b8 ea ff ff ff eb e1 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 <41> 57 41 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 ba 01 00 00 4c 8d
RSP: 0018:ffffc90003076f08 EFLAGS: 00000246
RAX: 1ffff9200060ee08 RBX: 0000000000000010 RCX: ffffffff81726938
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc90003077058
RBP: 0000000000000000 R08: 0000000000000003 R09: ffffffff81725d45
R10: ffffc90003077058 R11: ffffffff81aaf950 R12: ffffc90003077be0
R13: ffffc90003077058 R14: ffffc90003077058 R15: ffffc90003077050
__asan_memset+0x22/0x50 mm/kasan/shadow.c:84
unwind_next_frame+0xc98/0x2390 arch/x86/kernel/unwind_orc.c:592
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:308
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:2906
discard_slab mm/slub.c:3301 [inline]
__put_partials+0x146/0x170 mm/slub.c:3848
put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3923
__slab_free+0x2b9/0x390 mm/slub.c:5882
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:4946 [inline]
slab_alloc_node mm/slub.c:5245 [inline]
__do_kmalloc_node mm/slub.c:5602 [inline]
__kmalloc_noprof+0x3c3/0x7f0 mm/slub.c:5615
kmalloc_noprof include/linux/slab.h:961 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
tomoyo_encode+0x28b/0x550 security/tomoyo/realpath.c:80
tomoyo_realpath_from_path+0x58d/0x5d0 security/tomoyo/realpath.c:283
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_check_open_permission+0x1c1/0x3b0 security/tomoyo/file.c:771
security_file_open+0xb1/0x270 security/security.c:3183
do_dentry_open+0x384/0x13f0 fs/open.c:942
vfs_open+0x3b/0x340 fs/open.c:1097
do_open fs/namei.c:3975 [inline]
path_openat+0x2ee5/0x3830 fs/namei.c:4134
do_filp_open+0x1fa/0x410 fs/namei.c:4161
do_sys_openat2+0x121/0x1c0 fs/open.c:1437
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/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5313115c3a
RSP: 002b:00007ffe6e1d56a8 EFLAGS: 00000206 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000556353f8cf20 RCX: 00007f5313115c3a
RDX: 0000000000090800 RSI: 0000556353f473f0 RDI: 00000000ffffff9c
RBP: 0000556353f473f0 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000206 R12: 0000556353f537b0
R13: 00000000000000ff R14: 0000556340125be0 R15: 00007ffe6e1d5930
task:syz.8.1231 state:R running task stack:25000 pid:14465 tgid:14459 ppid:13444 task_flags:0x400040 flags:0x00080003
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]
wp_page_copy mm/memory.c:3780 [inline]
do_wp_page+0x1d1d/0x5800 mm/memory.c:4140
handle_pte_fault mm/memory.c:6193 [inline]
__handle_mm_fault+0x1033/0x5400 mm/memory.c:6318
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6487
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+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:__put_user_nocheck_4+0x3/0x10 arch/x86/lib/putuser.S:104
Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca e9 87 43 03 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb <89> 01 31 c9 0f 01 ca c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000b2278b8 EFLAGS: 00050202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000200000154030
RDX: ffff888027291e40 RSI: 0000000000000002 RDI: 00000000ffffffff
RBP: ffffc9000b227a30 R08: ffffc9000b227667 R09: 1ffff92001644ecc
R10: dffffc0000000000 R11: fffff52001644ecd R12: 0000000000000002
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000200000154000
____sys_recvmsg+0x2ab/0x460 net/socket.c:2863
___sys_recvmsg+0x1b5/0x510 net/socket.c:2892
do_recvmmsg+0x307/0x770 net/socket.c:2987
__sys_recvmmsg net/socket.c:3061 [inline]
__do_sys_recvmmsg net/socket.c:3084 [inline]
__se_sys_recvmmsg net/socket.c:3077 [inline]
__x64_sys_recvmmsg+0x190/0x240 net/socket.c:3077
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f480678eec9
RSP: 002b:00007f4807624038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f48069e6090 RCX: 00007f480678eec9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f4806811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f48069e6128 R14: 00007f48069e6090 R15: 00007f4806b0fa28
rcu: rcu_preempt kthread starved for 7733 jiffies! g54869 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:27320 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+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x436/0x7d0 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline]
RIP: 0010:lock_acquire+0x124/0x360 kernel/locking/lockdep.c:5870
Code: 02 00 00 41 0f 94 c1 4c 89 ef 89 de 8b 54 24 04 44 89 e1 45 89 f0 6a 00 6a 00 6a 00 55 ff 74 24 30 e8 e0 02 00 00 48 83 c4 28 <48> c7 c7 5f 52 6f 8d e8 10 c7 98 09 b8 ff ff ff ff 65 0f c1 05 63
RSP: 0018:ffffc90000006c98 EFLAGS: 00000082
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 5a73f725adfcd700
RDX: 0000000000000000 RSI: ffffffff8da95d80 RDI: ffffffff8da95200
RBP: ffffffff81725d45 R08: 0000000000000000 R09: ffffffff81725d45
R10: ffffc90000006e58 R11: ffffffff81aaf950 R12: 0000000000000002
R13: ffffffff8dd3b160 R14: 0000000000000000 R15: 0000000000000246
FS: 0000000000000000(0000) GS:ffff88812638a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9e46c00218 CR3: 00000000300b6000 CR4: 00000000003526f0
Call Trace:
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1169 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
__kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587
kasan_save_free_info mm/kasan/kasan.h:406 [inline]
poison_slab_object mm/kasan/common.c:252 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2514 [inline]
slab_free mm/slub.c:6566 [inline]
kmem_cache_free+0x19b/0x690 mm/slub.c:6676
nft_synproxy_eval_v4+0x376/0x560 net/netfilter/nft_synproxy.c:60
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+0x409/0x1920 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:6079 [inline]
__netif_receive_skb+0x143/0x380 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+0x283/0x870 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:702
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 f3 5a 13 00 f3 0f 1e fa fb f4 88 e6 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8da07d80 EFLAGS: 000002c2
RAX: 5a73f725adfcd700 RBX: ffffffff81954a27 RCX: 5a73f725adfcd700
RDX: 0000000000000001 RSI: ffffffff8d512c0f RDI: ffffffff8b9eea60
RBP: ffffffff8da07eb8 R08: ffff8880b8832fdb R09: 1ffff110171065fb
R10: dffffc0000000000 R11: ffffed10171065fc R12: ffffffff8f5bed30
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1b52a40
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
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
rest_init+0x2de/0x300 init/main.c:757
start_kernel+0x3ae/0x410 init/main.c:1111
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147