rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P15147/1:b..l P9/1:b..l
	(detected by 1, t=10502 jiffies, g=60745, q=19)
task:kworker/u4:0    state:R  running task     stack:21264 pid:    9 ppid:     2 flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0x4b/0x400 kernel/locking/lockdep.c:5591
Code: 30 48 89 4c 24 28 89 d3 89 74 24 1c 49 89 fc 65 48 8b 04 25 28 00 00 00 48 89 84 24 c0 00 00 00 49 bf 00 00 00 00 00 fc ff df <48> c7 44 24 60 b3 8a b5 41 48 c7 44 24 68 74 35 bc 8b 48 c7 44 24
RSP: 0018:ffffc90000ce7900 EFLAGS: 00000286
RAX: a8ba4f72c8f5e100 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c31eaa0
RBP: ffffc90000ce7a20 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1b13c6e R12: ffffffff8c31eaa0
R13: dffffc0000000000 R14: 0000000000000001 R15: dffffc0000000000
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313
 rcu_read_lock include/linux/rcupdate.h:740 [inline]
 batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:754 [inline]
 batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:825 [inline]
 batadv_iv_ogm_schedule+0x432/0xec0 net/batman-adv/bat_iv_ogm.c:868
 batadv_iv_send_outstanding_bat_ogm_packet+0x72f/0x840 net/batman-adv/bat_iv_ogm.c:1712
 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
task:syz.7.2217      state:R  running task     stack:27536 pid:15147 ppid:  7968 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:ns_of_pid include/linux/pid.h:-1 [inline]
RIP: 0010:task_active_pid_ns kernel/pid.c:509 [inline]
RIP: 0010:__task_pid_nr_ns+0x127/0x420 kernel/pid.c:499
Code: 00 00 8b 43 04 48 c1 e0 04 48 8d 9c 03 d8 00 00 00 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 8c 7c 6e 00 48 8b 1b <eb> 07 e8 22 71 29 00 31 db 31 ff 89 ee e8 77 74 29 00 85 ed 74 49
RSP: 0018:ffffc90002effee0 EFLAGS: 00000246
RAX: 1ffff11004563a95 RBX: ffff888063c0d630 RCX: ffff8880275cbb80
RDX: 0000000000000000 RSI: ffffffff8a79f960 RDI: ffff888022b1d3c4
RBP: 0000000000000001 R08: dffffc0000000000 R09: 1ffffffff203a818
R10: dffffc0000000000 R11: fffffbfff203a819 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff8880275cbb80 R15: 0000000000000001
 task_tgid_vnr include/linux/sched.h:1585 [inline]
 __ia32_sys_getpid+0x19/0x20 kernel/sys.c:945
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fde0aa94597
RSP: 002b:00007ffe232ef6c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000027
RAX: ffffffffffffffda RBX: 00007ffe232ef830 RCX: 00007fde0aa94597
RDX: 00007ffe232ef700 RSI: 00007ffe232ef830 RDI: 0000000000000021
RBP: 0000000000000000 R08: 000000000000000f R09: 0000000000000000
R10: 00007fde0ad13fa0 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fde0ad13fac R14: 00007fde0ad13fa8 R15: 00007fde0ad13fa0
 </TASK>
rcu: rcu_preempt kthread starved for 10552 jiffies! g60745 f0x0 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:27760 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
 rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x9b/0x370 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 15148 Comm: syz.8.2216 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:__list_del_entry_valid+0x45/0x120 lib/list_debug.c:47
Code: 48 c1 e8 03 42 80 3c 20 00 74 05 e8 25 07 d6 fd 4c 8b 7b 08 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 0b 07 d6 fd <4c> 8b 33 4d 85 f6 74 67 4d 85 ff 74 73 48 ba 00 01 00 00 00 00 ad
RSP: 0018:ffffc9000307faf8 EFLAGS: 00000046
RAX: 1ffff11005c2610a RBX: ffff88802e130850 RCX: 0000000000080000
RDX: ffffc9000e86c000 RSI: 000000000007ffff RDI: ffff88802e130858
RBP: ffff88802e130850 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200060ff58 R12: dffffc0000000000
R13: 1ffff110050609d1 R14: dffffc0000000000 R15: ffff888028304e78
FS:  00007f3fa05c46c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000c1000 CR3: 0000000073db3000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __list_del_entry include/linux/list.h:132 [inline]
 list_del_init include/linux/list.h:204 [inline]
 collect_signal kernel/signal.c:589 [inline]
 __dequeue_signal+0x279/0x5d0 kernel/signal.c:619
 dequeue_signal+0xa2/0x440 kernel/signal.c:639
 get_signal+0x6fe/0x12c0 kernel/signal.c:2781
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f3fa236a819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3fa05c40e8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f3fa25e3fa8 RCX: 00007f3fa236a819
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f3fa25e3fac
RBP: 00007f3fa25e3fa0 R08: 0024c28912aef5ea R09: 0000000000000000
R10: 0000000000000116 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3fa25e4038 R14: 00007ffe5990c3d0 R15: 00007ffe5990c4b8
 </TASK>