rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3452/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=12473, q=546 ncpus=2)
task:kworker/u4:8    state:R  running task     stack:24808 pid:3452  ppid:2      flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6701
 preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7011
 irqentry_exit+0x67/0x70 kernel/entry/common.c:441
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:rcu_preempt_read_exit kernel/rcu/tree_plugin.h:384 [inline]
RIP: 0010:__rcu_read_unlock+0x26/0xd0 kernel/rcu/tree_plugin.h:423
Code: 00 00 66 90 f3 0f 1e fa 41 57 41 56 41 55 41 54 53 49 bf 00 00 00 00 00 fc ff df 65 48 8b 3d 01 9c 91 7e 48 8d 9f 3c 04 00 00 <49> 89 dc 49 c1 ec 03 43 0f b6 04 3c 84 c0 75 48 ff 0b 75 1d 4c 8d
RSP: 0018:ffffc9000ce17b30 EFLAGS: 00000293
RAX: ffffffff8a5867cb RBX: ffff88802dcbc03c RCX: ffff88802dcbbc00
RDX: 0000000000000000 RSI: ffffffff8b1d3b80 RDI: ffff88802dcbbc00
RBP: 0000000000000000 R08: dffffc0000000000 R09: 1ffffffff223d6a0
R10: dffffc0000000000 R11: fffffbfff223d6a1 R12: dffffc0000000000
R13: ffffffff8a586692 R14: ffff88802f538d00 R15: dffffc0000000000
 rcu_read_unlock include/linux/rcupdate.h:818 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
 batadv_nc_worker+0x27c/0x600 net/batman-adv/network-coding.c:719
 process_one_work kernel/workqueue.c:2657 [inline]
 process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
rcu: rcu_preempt kthread starved for 10523 jiffies! g12473 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:27848 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6701
 schedule+0xbd/0x170 kernel/sched/core.c:6775
 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5981 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:get_current kernel/entry/common.c:268 [inline]
RIP: 0010:syscall_exit_to_user_mode_prepare+0x1/0xc0 kernel/entry/common.c:269
Code: 48 85 c0 74 09 48 8b 78 08 e8 cb f6 ff ff 65 ff 0d 4c 7b 8f 7e 75 94 e8 6d 60 8c ff eb 8d 0f 0b eb c4 0f 1f 80 00 00 00 00 55 <41> 57 41 56 53 50 65 48 8b 05 21 7b 8f 7e 48 8b 58 08 48 63 77 78
RSP: 0018:ffffc90003527f00 EFLAGS: 00000292
RAX: 0000000000000003 RBX: ffffc90003527f58 RCX: 2370c1ce0f162b00
RDX: 0000000000000000 RSI: ffffffff8acade60 RDI: ffffc90003527f58
RBP: ffffc90003527f48 R08: ffffffff8e8c316f R09: 1ffffffff1d1862d
R10: dffffc0000000000 R11: fffffbfff1d1862e R12: 0000000000000000
R13: 0000000000000000 R14: ffffc90003527f58 R15: 0000000000000027
FS:  00007fd8210566c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000058 CR3: 0000000075bb0000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0xd/0x50 kernel/entry/common.c:305
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd820197ed7
Code: 8d 3d 14 9f 0b 00 e8 58 1d fa ff e8 a3 87 00 00 0f 1f 00 b8 68 00 00 00 0f 05 c3 0f 1f 84 00 00 00 00 00 b8 27 00 00 00 0f 05 <c3> 0f 1f 84 00 00 00 00 00 b8 6e 00 00 00 0f 05 c3 0f 1f 84 00 00
RSP: 002b:00007fd821055b08 EFLAGS: 00000202 ORIG_RAX: 0000000000000027
RAX: 0000000000000003 RBX: 00007fd821055c70 RCX: 00007fd820197ed7
RDX: 00007fd821055b40 RSI: 00007fd821055c70 RDI: 0000000000000021
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fd820426038 R14: 00007ffe1673d500 R15: 00007ffe1673d5e8
 </TASK>
sched: RT throttling activated