rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4343/1:b..l
	(detected by 1, t=10502 jiffies, g=75009, q=1)
task:kworker/u4:9    state:R  running task     stack:22656 pid: 4343 ppid:     2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 preempt_schedule_irq+0xb1/0x150 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:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:205
Code: 84 00 00 00 00 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 50 d3 f1 0b 48 89 de 5b e9 57 9e 43 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d a4 a3 8a 7e 65 8b 15 a5 a3 8a 7e 81 e2 00 01 ff 00 74
RSP: 0018:ffffc9000463fbd8 EFLAGS: 00000202
RAX: ffffffff897e9bf5 RBX: dffffc0000000000 RCX: ffff888076625901
RDX: 0000000000000000 RSI: ffffffff8a59e560 RDI: ffffffff8a59e520
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1ff7c19
R10: fffffbfff1ff7c19 R11: 1ffffffff1ff7c18 R12: 00000000000002de
R13: fffffffffffffe38 R14: ffff888075788c80 R15: ffff888063e71190
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:413 [inline]
 batadv_nc_worker+0x175/0x5c0 net/batman-adv/network-coding.c:723
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread starved for 10514 jiffies! g75009 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:27168 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 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: 14275 Comm: syz.5.2536 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x32/0x60 kernel/kcov.c:206
Code: a4 a3 8a 7e 65 8b 15 a5 a3 8a 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 34 16 00 00 00 74 2c 8b 91 10 16 00 00 <83> fa 02 75 21 48 8b 91 18 16 00 00 48 8b 32 48 8d 7e 01 8b 89 14
RSP: 0018:ffffc9000337fb18 EFLAGS: 00000246
RAX: ffffffff812bc821 RBX: 00007ffc55854f00 RCX: ffff888023c91dc0
RDX: 0000000000000000 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580
RBP: ffffc9000337fcb0 R08: dffffc0000000000 R09: ffffed1027fd4481
R10: ffffed1027fd4481 R11: 1ffff11027fd4480 R12: dffffc0000000000
R13: 00007ffc55854f00 R14: ffff888023c93548 R15: ffff888023c91dc0
FS:  00005555704d3500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000058 CR3: 000000002a9fb000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 copy_fpstate_to_sigframe+0x871/0xb90 arch/x86/kernel/fpu/signal.c:214
 get_sigframe arch/x86/kernel/signal.c:295 [inline]
 __setup_rt_frame arch/x86/kernel/signal.c:471 [inline]
 setup_rt_frame arch/x86/kernel/signal.c:780 [inline]
 handle_signal arch/x86/kernel/signal.c:824 [inline]
 arch_do_signal_or_restart+0x67a/0x1300 arch/x86/kernel/signal.c:869
 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: 0033:0x7f6e4192a707
Code: 00 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 fb 44 8d 56 04 <4c> 8d 0d f2 48 38 00 89 f0 4c 8d 05 e9 28 38 00 89 c2 81 e2 ff 1f
RSP: 002b:00007ffc558552f8 EFLAGS: 00000246
RAX: 000000000000bf1e RBX: 00007f6e427f2720 RCX: 00000000000004aa
RDX: ffffffff83fb805b RSI: ffffffff83fb8143 RDI: 000000000000000b
RBP: ffffffff83fb8143 R08: 00007f6e41cc3128 R09: 00007f6e41caf000
R10: 0000000083fb8147 R11: 000000000000000b R12: 000000000000000b
R13: 0000000000000000 R14: ffffffff83fb805b R15: 00000000000004aa
 </TASK>