rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6956/1:b..l P11/1:b..l
	(detected by 0, t=10502 jiffies, g=27261, q=26 ncpus=2)
task:kworker/u4:1    state:R  running task     stack:23184 pid:11    ppid:2      flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0000:ffffc90000107a40 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: d1daf336c1021700
RDX: 0000000000000000 RSI: ffffffff8a6c1080 RDI: ffffffff8abf0ea0
RBP: ffffc90000107b58 R08: dffffc0000000000 R09: fffffbfff2116e49
R10: fffffbfff2116e49 R11: 1ffffffff2116e48 R12: 0000000000000000
R13: 1ffff92000020f54 R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 batadv_nc_process_nc_paths+0xdb/0x390 net/batman-adv/network-coding.c:687
 batadv_nc_worker+0x425/0x600 net/batman-adv/network-coding.c:728
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
task:syz.3.769       state:R  running task     stack:25728 pid:6956  ppid:4258   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730
 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0xf6/0x100 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 trie_update_elem+0xa22/0xe90 kernel/bpf/lpm_trie.c:445
 bpf_map_update_value+0x5a0/0x670 kernel/bpf/syscall.c:226
 generic_map_update_batch+0x569/0x850 kernel/bpf/syscall.c:1702
 bpf_map_do_batch+0x466/0x600 kernel/bpf/syscall.c:-1
 __sys_bpf+0x65f/0x6d0 kernel/bpf/syscall.c:-1
 __do_sys_bpf kernel/bpf/syscall.c:5124 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5122 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5122
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f963bd8e969
RSP: 002b:00007f963cc42038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f963bfb5fa0 RCX: 00007f963bd8e969
RDX: 0000000000000038 RSI: 0000200000000000 RDI: 000000000000001a
RBP: 00007f963be10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f963bfb5fa0 R15: 00007ffcf4126d58
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10552 jiffies! g27261 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=12434
rcu: rcu_preempt kthread starved for 10553 jiffies! g27261 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27464 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.1.135-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:736
Code: 48 89 df e8 87 55 b9 f7 e9 4c ff ff ff e8 4d 14 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 37 c3 4d 00 fb f4 <c3> 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffffff8c607d88 EFLAGS: 000002c6
RAX: 03962200790bc400 RBX: ffffffff8a18e0d7 RCX: 03962200790bc400
RDX: 0000000000000001 RSI: ffffffff8a6bff00 RDI: ffffffff8abf0ea0
RBP: ffffffff8c607ec0 R08: dffffc0000000000 R09: ffffed10171c6aee
R10: ffffed10171c6aee R11: 1ffff110171c6aed R12: 0000000000000000
R13: dffffc0000000000 R14: ffffffff8c6bc680 R15: 1ffffffff1bfcf8e
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3ca211 CR3: 000000004f52b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 default_idle_call+0x84/0xc0 kernel/sched/idle.c:109
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1fc/0x570 kernel/sched/idle.c:303
 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401
 rest_init+0x2dc/0x300 init/main.c:733
 arch_call_rest_init+0xa/0xa init/main.c:893
 start_kernel+0x490/0x539 init/main.c:1140
 secondary_startup_64_no_verify+0xcf/0xdb
 </TASK>