rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5616/1:b..l P4260/1:b..l
	(detected by 1, t=10502 jiffies, g=19485, q=204 ncpus=2)
task:udevd           state:R  running task     stack:23888 pid:4260  ppid:3638   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5710
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90003c87798 EFLAGS: 00000206
RAX: 3a04914bf76a8300 RBX: ffff88802e510000 RCX: 3a04914bf76a8300
RDX: 0000000000000000 RSI: ffffffff8a8c22a0 RDI: ffffffff8adf13a0
RBP: 0000000000000001 R08: ffff88802e510000 R09: 0000000000000004
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000246 R14: ffff88807e70c4d8 R15: ffff88802e510ae0
 lock_is_held include/linux/lockdep.h:283 [inline]
 mt_locked lib/maple_tree.c:-1 [inline]
 mt_slot lib/maple_tree.c:816 [inline]
 mas_slot lib/maple_tree.c:849 [inline]
 mas_get_slot lib/maple_tree.c:6680 [inline]
 mas_validate_gaps lib/maple_tree.c:6978 [inline]
 mt_validate+0x2e7f/0x4cb0 lib/maple_tree.c:7246
 validate_mm_mt+0xe2/0x440 mm/mmap.c:295
 __split_vma+0x30/0x500 mm/mmap.c:2355
 do_mas_align_munmap+0x397/0x12b0 mm/mmap.c:2480
 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650
 __vm_munmap+0x1ac/0x2d0 mm/mmap.c:2936
 __do_sys_munmap mm/mmap.c:2961 [inline]
 __se_sys_munmap mm/mmap.c:2958 [inline]
 __x64_sys_munmap+0x5c/0x70 mm/mmap.c:2958
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd32ad1e097
RSP: 002b:00007ffe33b78a08 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000556d36cb3e80 RCX: 00007fd32ad1e097
RDX: 0000556d36cb91c8 RSI: 0000000000000200 RDI: 00007fd32b3d5000
RBP: 0000000000000006 R08: 0000556d36cc68e0 R09: 0000000000000003
R10: 0000000000000040 R11: 0000000000000246 R12: 0000556d36cb20b0
R13: 00007fd32b50439c R14: 0000000000000c00 R15: 0000000000000009
 </TASK>
task:syz.3.312       state:R  running task     stack:26224 pid:5616  ppid:4276   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6731
 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6755
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 filemap_map_pages+0xf06/0x11c0 mm/filemap.c:3531
 do_fault_around mm/memory.c:4598 [inline]
 do_read_fault mm/memory.c:4624 [inline]
 do_fault mm/memory.c:4758 [inline]
 handle_pte_fault mm/memory.c:5029 [inline]
 __handle_mm_fault mm/memory.c:5171 [inline]
 handle_mm_fault+0x2991/0x3ee0 mm/memory.c:5292
 do_user_addr_fault+0x51f/0xb10 arch/x86/mm/fault.c:1338
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7fefa12716d6
RSP: 002b:00007ffcc0ccc8d0 EFLAGS: 00010202
RAX: 000000110c30c000 RBX: ffffffff81cd6dd8 RCX: 0000000000000003
RDX: 0000000000000dd8 RSI: 00000000000035b7 RDI: 0000000000000008
RBP: 0000000000000000 R08: 00007fefa1600000 R09: 00007fefa1602000
R10: 0000000081cd6ddc R11: 000000000000000f R12: 00007fefa1616038
R13: 000000000000006f R14: ffffffff81cd66cc R15: 00007fefa2145720
 </TASK>
rcu: rcu_preempt kthread starved for 9863 jiffies! g19485 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:27760 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </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:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:741