rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-....: (1 GPs behind) idle=bdf/1/0x4000000000000000 softirq=49477/49478 fqs=5245 
	(detected by 1, t=10502 jiffies, g=71381, q=1118)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 13059 Comm: kworker/u4:3 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__kasan_check_read+0x8/0x10 mm/kasan/shadow.c:31
Code: 5d c3 48 c7 c7 42 d0 de 8b eb 0a 48 c7 c7 5d e4 c4 8b 48 89 de e8 28 52 f3 07 31 ed eb d7 00 00 cc cc 89 f6 48 8b 0c 24 31 d2 <e9> 43 ef ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01 00 00 00 e9 30 ef
RSP: 0018:ffffc90000007a98 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 1ffff92000000f58 RCX: ffffffff81658169
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d89dc28
RBP: ffffc90000007b80 R08: ffff88802a80d947 R09: 1ffff11005501b28
R10: dffffc0000000000 R11: ffffed1005501b29 R12: ffff8880b903b208
R13: 0000000000000000 R14: ffff8880b903b1c0 R15: 1ffff11017207641
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000cf3d CR3: 000000000c08e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 cpumask_test_cpu include/linux/cpumask.h:344 [inline]
 cpu_online include/linux/cpumask.h:895 [inline]
 rcu_read_unlock_special+0x2f9/0x4a0 kernel/rcu/tree_plugin.h:662
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 BPF_PROG_RUN_ARRAY include/linux/bpf.h:1444 [inline]
 trace_call_bpf+0x4f9/0x5b0 kernel/trace/bpf_trace.c:127
 perf_trace_run_bpf_submit+0x79/0x1c0 kernel/events/core.c:10016
 perf_trace_preemptirq_template+0x2aa/0x360 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:ffs arch/x86/include/asm/bitops.h:297 [inline]
RIP: 0010:handle_softirqs+0x1a9/0x830 kernel/softirq.c:564
Code: 24 78 44 89 64 24 28 0f b7 db 48 c7 c7 80 0f 2a 8a e8 5b f8 72 08 65 66 c7 05 61 57 ba 7e 00 00 e8 5c 0c 36 00 fb 89 5c 24 34 <b8> ff ff ff ff 0f bc 44 24 34 41 89 c5 41 ff c5 0f 85 d2 00 00 00
RSP: 0018:ffffc90000007ee0 EFLAGS: 00000282
RAX: 74cb4e02dcc6ed00 RBX: 0000000000000200 RCX: 74cb4e02dcc6ed00
RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f800
RBP: ffffc90000007fe8 R08: ffffffff901d31b7 R09: 1ffffffff203a636
R10: dffffc0000000000 R11: fffffbfff203a637 R12: 000000000000000a
R13: dffffc0000000000 R14: ffff88802a80d940 R15: dffffc0000000000
 do_softirq+0x142/0x210 kernel/softirq.c:477
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x180/0x1c0 kernel/softirq.c:401
 spin_unlock_bh include/linux/spinlock.h:409 [inline]
 batadv_nc_purge_paths+0x316/0x3b0 net/batman-adv/network-coding.c:475
 batadv_nc_worker+0x327/0x5c0 net/batman-adv/network-coding.c:726
 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>