rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5227/1:b..l P5855/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=26349, q=767599 ncpus=2)
task:syz-executor state:R running task stack:20024 pid:5855 tgid:5855 ppid:5850 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__nr_to_section include/linux/mmzone.h:1937 [inline]
RIP: 0010:__pfn_to_section include/linux/mmzone.h:2079 [inline]
RIP: 0010:lookup_page_ext mm/page_ext.c:251 [inline]
RIP: 0010:page_ext_lookup+0x4d/0x180 mm/page_ext.c:509
Code: e6 49 c1 ee 16 e9 2d 01 00 00 e8 4e 78 91 ff 41 bf 00 00 04 00 49 bd 00 00 00 00 00 fc ff df 4c 89 f7 4c 89 fe e8 93 7a 91 ff <4d> 39 fe 0f 83 ef 00 00 00 48 c7 c0 00 70 b1 99 48 c1 e8 03 42 80
RSP: 0018:ffffc9000421f450 EFLAGS: 00000293
RAX: ffffffff822e337d RBX: 000000000006bf9d RCX: ffff888020f1da00
RDX: 0000000000000000 RSI: 0000000000001000 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff822e3e0a
R10: dffffc0000000000 R11: ffffed1004a4743a R12: 000000000006bf9d
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000001000
page_ext_iter_begin include/linux/page_ext.h:132 [inline]
__page_table_check_zero+0x18f/0x530 mm/page_table_check.c:139
page_table_check_free include/linux/page_table_check.h:43 [inline]
free_pages_prepare mm/page_alloc.c:1396 [inline]
__free_frozen_pages+0xbd7/0xd30 mm/page_alloc.c:2895
discard_slab mm/slub.c:2753 [inline]
__put_partials+0x156/0x1a0 mm/slub.c:3218
put_cpu_partial+0x17c/0x250 mm/slub.c:3293
__slab_free+0x2d5/0x3c0 mm/slub.c:4550
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:340
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4180 [inline]
slab_alloc_node mm/slub.c:4229 [inline]
__kmalloc_cache_node_noprof+0x1c0/0x3d0 mm/slub.c:4404
kmalloc_node_noprof include/linux/slab.h:928 [inline]
__get_vm_area_node+0x13f/0x300 mm/vmalloc.c:3176
__vmalloc_node_range_noprof+0x301/0x12f0 mm/vmalloc.c:3853
__vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:3956
alloc_thread_stack_node kernel/fork.c:311 [inline]
dup_task_struct+0x3e7/0x860 kernel/fork.c:882
copy_process+0x54b/0x3c00 kernel/fork.c:2004
kernel_clone+0x21e/0x840 kernel/fork.c:2605
__do_sys_clone kernel/fork.c:2748 [inline]
__se_sys_clone kernel/fork.c:2732 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2732
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: 0033:0x7fe505585453
RSP: 002b:00007ffc685aa1b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe505585453
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555859f67d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000423bb R15: 00007ffc685aa350
task:udevd state:R running task stack:21736 pid:5227 tgid:5227 ppid:1 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:memset+0xf/0x20 arch/x86/lib/memset_64.S:38
Code: 44 88 1f e9 ae e4 96 f5 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 49 89 f9 40 88 f0 48 89 d1 aa 4c 89 c8 e9 82 e4 96 f5 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90003e6f030 EFLAGS: 00000202
RAX: 1ffff920007cde00 RBX: ffffc90003e6f140 RCX: 000000000000000f
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90003e6f159
RBP: dffffc0000000000 R08: ffffc90003e6f167 R09: ffffc90003e6f158
R10: dffffc0000000000 R11: fffff520007cde2d R12: ffffc90003e6f548
R13: ffffc90003e6f158 R14: ffffc90003e6f108 R15: ffffc90003e6f150
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:1395 [inline]
__free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
__slab_free+0x303/0x3c0 mm/slub.c:4591
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_kmalloc+0x22/0xb0 mm/kasan/common.c:396
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4365 [inline]
__kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4377
kmalloc_noprof include/linux/slab.h:909 [inline]
tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
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:3144
do_dentry_open+0x384/0x13f0 fs/open.c:942
vfs_open+0x3b/0x340 fs/open.c:1095
do_open fs/namei.c:3887 [inline]
path_openat+0x2ee5/0x3830 fs/namei.c:4046
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1435
do_sys_open fs/open.c:1450 [inline]
__do_sys_openat fs/open.c:1466 [inline]
__se_sys_openat fs/open.c:1461 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1461
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: 0033:0x7f6492ca7407
RSP: 002b:00007ffd2ce6f470 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f649334d880 RCX: 00007f6492ca7407
RDX: 0000000000080141 RSI: 000055add210a02e RDI: ffffffffffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000001a4 R11: 0000000000000202 R12: 00000000ffffffff
R13: 00000000ffffffff R14: ffffffffffffffff R15: 0000000000000000
rcu: rcu_preempt kthread starved for 10503 jiffies! g26349 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:27224 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
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+0x3fc/0x770 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: 3421 Comm: kworker/R-bat_e Not tainted 6.16.0-syzkaller-12288-g2b38afce25c4 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: bat_events batadv_dat_purge
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 eb e3 02 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90000a07618 EFLAGS: 00000206
RAX: 5b77fec9ee19c000 RBX: 0000000000000000 RCX: 5b77fec9ee19c000
RDX: 0000000000000000 RSI: ffffffff8dba5fb5 RDI: ffffffff8be33380
RBP: ffffffff8172c195 R08: 0000000000000000 R09: ffffffff8172c195
R10: dffffc0000000000 R11: ffffffff81ac3890 R12: 0000000000000002
R13: ffffffff8e139ee0 R14: 0000000000000000 R15: 0000000000000246
FS: 0000000000000000(0000) GS:ffff888125d1c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe5062e56c0 CR3: 00000000726d4000 CR4: 0000000000350ef0
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:1155 [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:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405
kasan_kmalloc include/linux/kasan.h:260 [inline]
__kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4396
kmalloc_noprof include/linux/slab.h:905 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
ref_tracker_alloc+0x133/0x460 lib/ref_tracker.c:271
__netdev_tracker_alloc include/linux/netdevice.h:4346 [inline]
netdev_hold include/linux/netdevice.h:4375 [inline]
dst_init+0xd9/0x450 net/core/dst.c:52
dst_alloc+0x12a/0x170 net/core/dst.c:93
rt_dst_alloc net/ipv4/route.c:1645 [inline]
__mkroute_output net/ipv4/route.c:2645 [inline]
ip_route_output_key_hash_rcu+0x14e1/0x23d0 net/ipv4/route.c:2866
ip_route_output_key_hash+0x1b9/0x2e0 net/ipv4/route.c:2696
__ip_route_output_key include/net/route.h:169 [inline]
ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2923
ip_route_output_key include/net/route.h:179 [inline]
ip_route_me_harder+0x6d2/0x1030 net/ipv4/netfilter.c:53
synproxy_send_tcp+0x359/0x6c0 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:5979 [inline]
__netif_receive_skb+0x143/0x380 net/core/dev.c:6092
process_backlog+0x60e/0x14f0 net/core/dev.c:6444
__napi_poll+0xc7/0x360 net/core/dev.c:7489
napi_poll net/core/dev.c:7552 [inline]
net_rx_action+0x707/0xe30 net/core/dev.c:7679
handle_softirqs+0x286/0x870 kernel/softirq.c:579
do_softirq+0xec/0x180 kernel/softirq.c:480
__local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407
spin_unlock_bh include/linux/spinlock.h:396 [inline]
__batadv_dat_purge net/batman-adv/distributed-arp-table.c:185 [inline]
batadv_dat_purge+0x2da/0x3c0 net/batman-adv/distributed-arp-table.c:204
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
rescuer_thread+0x53c/0xdd0 kernel/workqueue.c:3496
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245