rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P1147/1:b..l P5821/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=30037, q=267 ncpus=2)
task:syz-executor    state:R  running task     stack:23728 pid:5821  tgid:5821  ppid:5811   task_flags:0x400140 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0xf43/0x5890 kernel/sched/core.c:6765
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6944
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 copy_pte_range mm/memory.c:1201 [inline]
 copy_pmd_range mm/memory.c:1262 [inline]
 copy_pud_range mm/memory.c:1299 [inline]
 copy_p4d_range mm/memory.c:1323 [inline]
 copy_page_range+0x1deb/0x5570 mm/memory.c:1421
 dup_mmap kernel/fork.c:748 [inline]
 dup_mm kernel/fork.c:1700 [inline]
 copy_mm kernel/fork.c:1752 [inline]
 copy_process+0x7ccb/0x8c50 kernel/fork.c:2403
 kernel_clone+0xfd/0x960 kernel/fork.c:2815
 __do_sys_clone+0xcf/0x120 kernel/fork.c:2958
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f408f9839d3
RSP: 002b:00007ffe3fe12fb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f408f9839d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 0000555573aec7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000591e0 R15: 00007ffe3fe13150
 </TASK>
task:kworker/u8:5    state:R  running task     stack:22448 pid:1147  tgid:1147  ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0xf43/0x5890 kernel/sched/core.c:6765
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7087
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:rcu_is_watching+0x83/0xc0 kernel/rcu/tree.c:719
Code: c1 ea 03 0f b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 24 8b 03 c1 e8 02 83 e0 01 65 ff 0d 18 42 64 7e 74 07 5b <5d> c3 cc cc cc cc e8 12 5e 8c ff 5b 5d c3 cc cc cc cc 48 89 df e8
RSP: 0018:ffffc90003cd7b18 EFLAGS: 00000286
RAX: 0000000000000001 RBX: ffff888031880f10 RCX: ffffffff8b260c3b
RDX: 0000000000000000 RSI: ffffffff8bd36b20 RDI: ffffffff8dab4ce0
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000002 R12: 0000000000000001
R13: 0000000000000001 R14: 0000000000000000 R15: dffffc0000000000
 rcu_read_lock include/linux/rcupdate.h:850 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0xc02/0x1060 net/batman-adv/network-coding.c:719
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3400
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: rcu_preempt kthread starved for 10191 jiffies! g30037 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:27520 pid:18    tgid:18    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0xf43/0x5890 kernel/sched/core.c:6765
 __schedule_loop kernel/sched/core.c:6842 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6857
 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111