syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7216/1:b..l
	(detected by 1, t=10502 jiffies, g=39629, q=437 ncpus=2)
task:rm              state:R  running task     stack:22968 pid:7216  ppid:7160   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5243 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6560
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6872
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666
Code: 2b 00 74 08 4c 89 f7 e8 4f 55 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc90004bde3c0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff9200097bc84 RCX: 1ffff9200097bc24
RDX: dffffc0000000000 RSI: ffffffff8b0c2ec0 RDI: ffffffff8b5f6f80
RBP: ffffc90004bde510 R08: dffffc0000000000 R09: fffffbfff225724d
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200097bc80
R13: dffffc0000000000 R14: ffffc90004bde420 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 is_bpf_text_address+0x3e/0x2a0 kernel/bpf/core.c:735
 kernel_text_address+0x9f/0xd0 kernel/extable.c:125
 __kernel_text_address+0x9/0x40 kernel/extable.c:79
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf3/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2845
 mas_wr_node_store lib/maple_tree.c:4220 [inline]
 mas_wr_modify+0x2a4d/0x4b90 lib/maple_tree.c:4419
 mas_store_prealloc+0x304/0x460 lib/maple_tree.c:5787
 __vma_adjust+0x183f/0x1f40 mm/mmap.c:823
 __split_vma+0x36c/0x4c0
 do_mas_align_munmap+0x42f/0x15a0 mm/mmap.c:2468
 do_mas_munmap+0x246/0x2b0 mm/mmap.c:2638
 __mmap_region mm/mmap.c:2686 [inline]
 mmap_region+0x8d4/0x2660 mm/mmap.c:2904
 do_mmap+0x8c5/0xf60 mm/mmap.c:1424
 vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:520
 ksys_mmap_pgoff+0x4f5/0x6d0 mm/mmap.c:1470
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f04354a0b74
RSP: 002b:00007ffeade8ba38 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007ffeade8bae8 RCX: 00007f04354a0b74
RDX: 0000000000000003 RSI: 0000000000006000 RDI: 00007f04353ad000
RBP: 00007ffeade8c1d0 R08: 0000000000000003 R09: 000000000019d000
R10: 0000000000000812 R11: 0000000000000246 R12: 00007f04354835c0
R13: 00007ffeade8c258 R14: 000000000019d264 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 9940 jiffies! g39629 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:26712 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5243 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6560
 schedule+0xbf/0x180 kernel/sched/core.c:6636
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 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 acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567