rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6811/1:b..l P5223/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=24205, q=273 ncpus=2)
task:udevd           state:R  running task     stack:24008 pid:5223  tgid:5223  ppid:1      task_flags:0x400140 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7145
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:194
 sock_def_readable+0x15b/0x600 net/core/sock.c:3542
 __netlink_sendskb net/netlink/af_netlink.c:1265 [inline]
 netlink_sendskb net/netlink/af_netlink.c:1271 [inline]
 netlink_unicast+0x75c/0x870 net/netlink/af_netlink.c:1361
 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg net/socket.c:729 [inline]
 ____sys_sendmsg+0xa98/0xc70 net/socket.c:2614
 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668
 __sys_sendmsg+0x16d/0x220 net/socket.c:2700
 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: 0033:0x7efdeabd4407
RSP: 002b:00007fffb85b2e90 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007efdeab48880 RCX: 00007efdeabd4407
RDX: 0000000000000000 RSI: 00007fffb85b2ef0 RDI: 0000000000000004
RBP: 00005622c9749160 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000076
R13: 00005622c94fcd80 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
task:kworker/u8:11   state:R  running task     stack:23560 pid:6811  tgid:6811  ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288
 irqentry_exit+0x36/0x90 kernel/entry/common.c:197
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:in_irqentry_text kernel/stacktrace.c:380 [inline]
RIP: 0010:filter_irq_stacks+0x48/0x90 kernel/stacktrace.c:397
Code: ea 03 80 3c 1a 00 75 4a 48 8b 17 48 81 fa 30 02 00 81 72 16 48 81 fa 70 16 00 81 73 0d 83 c0 01 48 83 c4 10 5b e9 98 71 f0 09 <48> 81 fa e0 44 97 8b 72 09 48 81 fa fb 44 97 8b 72 e1 83 c0 01 48
RSP: 0018:ffffc9001a6c7748 EFLAGS: 00000202
RAX: 000000000000000b RBX: dffffc0000000000 RCX: 0000000000000001
RDX: ffffffff812c109a RSI: 000000000000000c RDI: ffffc9001a6c7818
RBP: 0000000000000820 R08: ffffffff913b689c R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000002c10 R12: 0000000000000001
R13: 0000000000000820 R14: ffff8880761a8b40 R15: ffffc9001a6c77c0
 stack_depot_save_flags+0x29/0x9c0 lib/stackdepot.c:659
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:48
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:405
 kmalloc_noprof include/linux/slab.h:905 [inline]
 batadv_forw_packet_alloc+0x3ad/0x4e0 net/batman-adv/send.c:520
 batadv_iv_ogm_aggregate_new+0x13c/0x4c0 net/batman-adv/bat_iv_ogm.c:571
 batadv_iv_ogm_queue_add net/batman-adv/bat_iv_ogm.c:678 [inline]
 batadv_iv_ogm_schedule_buff+0xeb4/0x14c0 net/batman-adv/bat_iv_ogm.c:855
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:874 [inline]
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:867 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x329/0x920 net/batman-adv/bat_iv_ogm.c:1714
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread starved for 9809 jiffies! g24205 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:27784 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7058
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2285
 kthread+0x3c2/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
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 07/12/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: cc 61 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 53 b3 15 00 fb f4 <e9> 8c 09 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df8 EFLAGS: 000002c2
RAX: 00000000012be075 RBX: 0000000000000001 RCX: ffffffff8b945c29
RDX: 0000000000000000 RSI: ffffffff8de522e8 RDI: ffffffff8c162d80
RBP: ffffed1003cd3488 R08: 0000000000000001 R09: ffffed10170a6655
R10: ffff8880b85332ab R11: 0000000000000000 R12: 0000000000000001
R13: ffff88801e69a440 R14: ffffffff90ab6b90 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881247b5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000026a030 CR3: 000000005b9a2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:757
 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:190 [inline]
 do_idle+0x391/0x510 kernel/sched/idle.c:330
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428
 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315
 common_startup_64+0x13e/0x148
 </TASK>