rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6661/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=20685, q=342 ncpus=2)
task:syz.1.391       state:R  running task     stack:25168 pid:6661  tgid:6659  ppid:5083   flags:0x00004002
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:__sanitizer_cov_trace_switch+0x16/0x90 kernel/kcov.c:324
Code: 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 56 41 55 41 54 49 89 fc 55 48 89 f5 53 48 8b 46 08 <48> 83 f8 20 74 6b 77 48 48 83 f8 08 74 5b 48 83 f8 10 75 2f 41 bd
RSP: 0018:ffffc900030ff590 EFLAGS: 00000206
RAX: 0000000000000020 RBX: 0000000000000003 RCX: ffffc9000a53d000
RDX: ffff888062fef000 RSI: ffffffff8c818b00 RDI: 0000000000000003
RBP: ffffffff8c818b00 R08: 0000000000000005 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000003
R13: ffffc900030ff790 R14: ffffc900030ff6d0 R15: 0000000000000300
 ma_pivots lib/maple_tree.c:654 [inline]
 mtree_range_walk+0x311/0xbe0 lib/maple_tree.c:2770
 mas_state_walk lib/maple_tree.c:3678 [inline]
 mt_find+0x5af/0xa20 lib/maple_tree.c:6935
 find_vma+0xc0/0x140 mm/mmap.c:1948
 lock_mm_and_find_vma+0x62/0x6a0 mm/memory.c:5779
 do_user_addr_fault+0x29c/0xe50 arch/x86/mm/fault.c:1361
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:rep_movs_alternative+0x4a/0x70 arch/x86/lib/copy_user_64.S:71
Code: 75 f1 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 <f3> a4 c3 cc cc cc cc 48 89 c8 48 c1 e9 03 83 e0 07 f3 48 a5 89 c1
RSP: 0018:ffffc900030ff958 EFLAGS: 00050206
RAX: 0000000000000001 RBX: 0000000000001000 RCX: 0000000000000e80
RDX: 0000000000000000 RSI: ffff888012e72180 RDI: 0000000020155000
RBP: 0000000000001000 R08: 0000000000000000 R09: ffffed10025ce5ff
R10: ffff888012e72fff R11: 0000000000000000 R12: 0000000000154b80
R13: ffffc900030ffd50 R14: ffff888012e72000 R15: 0000000020154e80
 copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:131 [inline]
 copy_to_user_iter lib/iov_iter.c:25 [inline]
 iterate_iovec include/linux/iov_iter.h:51 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:247 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x4d2/0x1140 lib/iov_iter.c:185
 copy_page_to_iter lib/iov_iter.c:362 [inline]
 copy_page_to_iter+0xf1/0x180 lib/iov_iter.c:349
 process_vm_rw_pages mm/process_vm_access.c:45 [inline]
 process_vm_rw_single_vec mm/process_vm_access.c:118 [inline]
 process_vm_rw_core.constprop.0+0x5c9/0xa10 mm/process_vm_access.c:216
 process_vm_rw+0x301/0x360 mm/process_vm_access.c:284
 __do_sys_process_vm_readv mm/process_vm_access.c:296 [inline]
 __se_sys_process_vm_readv mm/process_vm_access.c:292 [inline]
 __x64_sys_process_vm_readv+0xe2/0x1c0 mm/process_vm_access.c:292
 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: 0033:0x7f6b1c975b29
RSP: 002b:00007f6b1d7ea048 EFLAGS: 00000246 ORIG_RAX: 0000000000000136
RAX: ffffffffffffffda RBX: 00007f6b1cb04070 RCX: 00007f6b1c975b29
RDX: 0000000000000002 RSI: 0000000020008400 RDI: 000000000000013f
RBP: 00007f6b1c9f6756 R08: 0000000000000286 R09: 0000000000000000
R10: 0000000020008640 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f6b1cb04070 R15: 00007ffff7a7c2c8
 </TASK>
rcu: rcu_preempt kthread starved for 10510 jiffies! g20685 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27312 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 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112