rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P30/1:b..l
	(detected by 1, t=10502 jiffies, g=31189, q=11 ncpus=2)
task:kworker/u4:2    state:R  running task     stack:21152 pid:30    ppid:2      flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 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:debug_lockdep_rcu_enabled+0x25/0x30 kernel/rcu/update.c:281
Code: 00 00 cc cc 00 31 c0 83 3d e7 93 07 04 00 74 1d 83 3d 72 c7 07 04 00 74 14 65 48 8b 0d 44 97 ea 75 31 c0 83 b9 dc 0a 00 00 00 <0f> 94 c0 c3 00 00 cc cc 00 00 cc 48 8b 3c 24 e8 47 fb ff ff 66 90
RSP: 0018:ffffc90000a6fbd8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88807e7cafc0 RCX: ffff88801d243b80
RDX: 0000000000000000 RSI: ffffffff8a8c1700 RDI: ffffffff8adef760
RBP: ffff8880757bc0c0 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: dffffc0000000000
R13: ffffffff89e1baae R14: ffff8880659d0c80 R15: 0000000000000018
 rcu_read_lock include/linux/rcupdate.h:792 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0xf4/0x600 net/batman-adv/network-coding.c:719
 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>
rcu: rcu_preempt kthread starved for 10523 jiffies! g31189 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:27200 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:2167
 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6651 Comm: syz.7.438 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:copy_user_generic arch/x86/include/asm/uaccess_64.h:46 [inline]
RIP: 0010:raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline]
RIP: 0010:_copy_from_user+0xf4/0x170 lib/usercopy.c:23
Code: fd 49 29 dc 72 61 4d 39 fc 72 5c e8 e6 ac 79 fd 0f ae e8 4c 89 f7 89 de e8 79 dd c9 fd 4c 89 fe 4c 89 f7 89 da e8 cc 50 04 06 <41> 89 c7 31 ff 4c 89 fe e8 9f b0 79 fd 4d 85 ff 75 11 e8 b5 ac 79
RSP: 0018:ffffc90005f67bd0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000018 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00007f4feadf5b68 RDI: ffffc90005f67c78
RBP: 0000000000000000 R08: 0000000000000000 R09: fffff52000becf8f
R10: fffff52000becf8f R11: 1ffff92000becf8c R12: 00007fffffffefe8
R13: dffffc0000000000 R14: ffffc90005f67c60 R15: 00007f4feadf5b50
FS:  00007f4feadf66c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005623d0d2e950 CR3: 00000000562d1000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 copy_from_user include/linux/uaccess.h:161 [inline]
 restore_altstack+0x9a/0x4a0 kernel/signal.c:4257
 __ia32_sys_rt_sigreturn+0x660/0x790 arch/x86/kernel/signal.c:678
 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: 0033:0x7f4fecb8f747
Code: ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89
RSP: 002b:00007f4feadf60e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f4fecde5fa8 RCX: 00007f4fecb8f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f4fecde5fa8
RBP: 00007f4fecde5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4fecde6038 R14: 00007ffe95cf20c0 R15: 00007ffe95cf21a8
 </TASK>