rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P1147/1:b..l
	(detected by 1, t=10503 jiffies, g=7181, q=161)
task:kworker/u4:3    state:R  running task     stack:22808 pid: 1147 ppid:     2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5029 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6375
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6779
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:202
Code: 1f 84 00 00 00 00 00 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 28 05 8a 0c 48 89 de 5b e9 37 1b 49 00 cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0d f4 d2 81 7e 65 8b 15 f5 d2 81 7e 81 e2 00
RSP: 0018:ffffc900051d7b88 EFLAGS: 00000202
RAX: 0000000000007501 RBX: 0000000000000001 RCX: ffff888021b4d940
RDX: ffff888021b4d940 RSI: ffffffff8af9fa60 RDI: ffffffff8af9fa20
RBP: 0000000000000001 R08: ffffffff8a1d3be9 R09: fffffbfff2131e19
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1100c6532f3
R13: ffff888063298c80 R14: ffff88814779e850 R15: ffffffff8a1d3d00
 rcu_read_unlock include/linux/rcupdate.h:768 [inline]
 batadv_nc_process_nc_paths+0x250/0x350 net/batman-adv/network-coding.c:703
 batadv_nc_worker+0x3d4/0x5b0 net/batman-adv/network-coding.c:732
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread starved for 10526 jiffies! g7181 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:27000 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5029 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6375
 schedule+0x11b/0x1f0 kernel/sched/core.c:6458
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 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: 4314 Comm: syz.3.30 Not tainted 5.15.179-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:trace_hardirqs_on+0x1/0x80 kernel/trace/trace_preemptirq.c:41
Code: fe ff ff e8 a1 81 f9 ff 0f 0b e9 21 ff ff ff e8 95 81 f9 ff e8 88 71 79 ff e9 59 fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 53 <e8> 7a 81 f9 ff 65 8b 1d 6b 17 7c 7e 31 ff 89 de e8 ca 84 f9 ff 85
RSP: 0018:ffffc9000324f9d0 EFLAGS: 00000097
RAX: 0000000080000001 RBX: 1ffff92000649f40 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffffc9000324fa90 R08: ffffffff815528e6 R09: ffffed1027fe3c81
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff92000649f44 R14: ffffc9000324fa20 R15: 0000000000000200
FS:  00007f284a2e26c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000040000006b000 CR3: 000000007506a000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 __local_bh_enable_ip+0x164/0x1f0 kernel/softirq.c:388
 fpregs_unlock arch/x86/include/asm/fpu/api.h:78 [inline]
 restore_fpregs_from_user arch/x86/kernel/fpu/signal.c:300 [inline]
 __fpu_restore_sig arch/x86/kernel/fpu/signal.c:334 [inline]
 fpu__restore_sig+0x841/0x1100 arch/x86/kernel/fpu/signal.c:466
 restore_sigcontext+0x638/0x710 arch/x86/kernel/signal.c:139
 __do_sys_rt_sigreturn+0x190/0x250 arch/x86/kernel/signal.c:674
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f284c479167
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:00007f284a2e20e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f284c691fa8 RCX: 00007f284c479169
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f284c691fa8
RBP: 00007f284c691fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f284c691fac
R13: 0000000000000000 R14: 00007ffc7988f980 R15: 00007ffc7988fa68
 </TASK>
sched: RT throttling activated