rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P19008/1:b..l P21195/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=131217, q=303 ncpus=2)
task:syz.1.3092      state:R  running task     stack:27872 pid:21195 tgid:21193 ppid:15674  flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0xf15/0x5d00 kernel/sched/core.c:6745
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6924
 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]
 zap_pte_range mm/memory.c:1676 [inline]
 zap_pmd_range mm/memory.c:1724 [inline]
 zap_pud_range mm/memory.c:1753 [inline]
 zap_p4d_range mm/memory.c:1774 [inline]
 unmap_page_range+0xbc7/0x3f20 mm/memory.c:1795
 unmap_single_vma+0x194/0x2b0 mm/memory.c:1841
 unmap_vmas+0x22f/0x490 mm/memory.c:1885
 exit_mmap+0x1b8/0xb20 mm/mmap.c:3341
 __mmput+0x12a/0x4d0 kernel/fork.c:1346
 mmput+0x62/0x70 kernel/fork.c:1368
 exit_mm kernel/exit.c:567 [inline]
 do_exit+0x9b7/0x2ba0 kernel/exit.c:863
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1025
 get_signal+0x2616/0x2710 kernel/signal.c:2909
 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x14a/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ca2775bd9
RSP: 002b:00007f5ca349b0f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f5ca2904040 RCX: 00007f5ca2775bd9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f5ca2904040
RBP: 00007f5ca2904038 R08: 00007f5ca349b6c0 R09: 00007f5ca349b6c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5ca2904044
R13: 000000000000006e R14: 00007ffc6c5c7680 R15: 00007ffc6c5c7768
 </TASK>
task:kworker/u8:1    state:R  running task     stack:24560 pid:19008 tgid:19008 ppid:2      flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0xf15/0x5d00 kernel/sched/core.c:6745
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7067
 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:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5722
Code: c1 05 da ac 96 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc9000303fa70 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff92000607f50 RCX: 0000000030f0905e
RDX: 0000000000000001 RSI: ffffffff8b2cb200 RDI: ffffffff8b903940
RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff284d858
R10: ffffffff9426c2c7 R11: 0000000000000003 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8dbb1620 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
 rcu_read_lock include/linux/rcupdate.h:781 [inline]
 batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:754 [inline]
 batadv_iv_ogm_schedule_buff+0x5ac/0x1500 net/batman-adv/bat_iv_ogm.c:825
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:868 [inline]
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:861 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x31e/0x8d0 net/batman-adv/bat_iv_ogm.c:1712
 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3248
 process_scheduled_works kernel/workqueue.c:3329 [inline]
 worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: rcu_preempt kthread starved for 10420 jiffies! g131217 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:27680 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0xf15/0x5d00 kernel/sched/core.c:6745
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6837
 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2000
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2202
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 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:86 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111