rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=13389, q=356 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294965172-4294954670), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g13389 f0x2 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:27784 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x116a/0x5de0 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6878
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </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 UID: 0 PID: 5943 Comm: kworker/u8:9 Not tainted 6.16.0-rc3-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__kasan_check_read+0xa/0x20 mm/kasan/shadow.c:31
Code: c7 c7 a8 9d c6 8d 5b 5d 41 5c e9 11 ef 77 ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 89 f6 <31> d2 e9 5f f0 ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00
RSP: 0018:ffffc90000007d10 EFLAGS: 00000046
RAX: 0000000000000007 RBX: ffffffff9b040918 RCX: ffffffff8198ca33
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff9b040918
RBP: 0000000000000002 R08: 0000000000000001 R09: fffff52000000f98
R10: 0000000000000003 R11: 0000000000000001 R12: 0000000000000001
R13: dffffc0000000000 R14: ffff888033360340 R15: 1ffff92000000fac
FS:  0000000000000000(0000) GS:ffff888124753000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2eefeff8 CR3: 000000002a008000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
 queued_spin_is_locked include/asm-generic/qspinlock.h:57 [inline]
 debug_spin_unlock kernel/locking/spinlock_debug.c:101 [inline]
 do_raw_spin_unlock+0x53/0x230 kernel/locking/spinlock_debug.c:141
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:150 [inline]
 _raw_spin_unlock_irqrestore+0x22/0x80 kernel/locking/spinlock.c:194
 debug_object_deactivate+0x1ec/0x3a0 lib/debugobjects.c:888
 debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline]
 debug_deactivate kernel/time/hrtimer.c:490 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1729 [inline]
 __hrtimer_run_queues+0x46f/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x3d/0xc0 kernel/rcu/tree.c:745
Code: c7 c3 28 02 ce 93 89 c5 83 f8 07 0f 87 82 00 00 00 48 8d 3c ed a0 6d f2 8d 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 5c 48 03 1c ed a0 6d f2 8d 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc9000437fa40 EFLAGS: 00000a06
RAX: dffffc0000000000 RBX: ffffffff93ce0228 RCX: ffffffff8198c6bc
RDX: 1ffffffff1be4db4 RSI: ffffffff8c1579a0 RDI: ffffffff8df26da0
RBP: 0000000000000000 R08: 0000000000000001 R09: fffff5200086ff48
R10: 0000000000000003 R11: 0000000000000001 R12: ffffffff8b4d2fe4
R13: ffff88803687d480 R14: ffff888078f48d80 R15: 0000000000000000
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0x201/0x2f0 kernel/locking/lockdep.c:5882
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:165 [inline]
 _raw_spin_unlock_bh+0x16/0x30 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 batadv_nc_purge_paths+0x1d4/0x3a0 net/batman-adv/network-coding.c:471
 batadv_nc_worker+0x921/0x1030 net/batman-adv/network-coding.c:720
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>