syzbot

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kernel BUG at [] mm/page_table_check.c:118!
Kernel BUG [#1]
Modules linked in:
CPU: 1 UID: 0 PID: 3923 Comm: syz.1.22 Tainted: G        W           syzkaller #0 PREEMPT 
Tainted: [W]=WARN
Hardware name: riscv-virtio,qemu (DT)
epc : page_table_check_set+0x996/0xc38 mm/page_table_check.c:118
 ra : page_table_check_set+0x996/0xc38 mm/page_table_check.c:118
epc : ffffffff80c8200a ra : ffffffff80c8200a sp : ffff8f800a136fd0
 gp : ffffffff8a49d240 tp : ffffaf801ce60000 t0 : ffffaf8021091de0
 t1 : fffff5ef027ad009 t2 : ffffffff80a9b828 s0 : ffff8f800a137050
 s1 : 0000000000000001 a0 : 0000000000000001 a1 : 0000000000000000
 a2 : 0000000000080000 a3 : ffffffff80c8200a a4 : ffff8f8004ee1048
 a5 : 00000000000a6048 a6 : 0000000000000003 a7 : ffffaf8013d6804b
 s2 : 00000000000b4800 s3 : 0000000000000000 s4 : ffffaf8013d68000
 s5 : 0000000000000200 s6 : 0000000000000001 s7 : dfffffff00000000
 s8 : 0000000000007fff s9 : ffffffff88c5a000 s10: 0000000000000000
 s11: ffffffff8a5bbca0 t3 : 0000000000000001 t4 : fffff5ef027ad009
 t5 : fffff5ef027ad00a t6 : 0000000000000002 ssp : 0000000000000000
status: 0000000200000120 badaddr: ffffffff80c8200a cause: 0000000000000003
[<ffffffff80c8200a>] page_table_check_set+0x996/0xc38 mm/page_table_check.c:118
[<ffffffff80c82774>] __page_table_check_ptes_set+0x264/0x47c mm/page_table_check.c:212
[<ffffffff80c0b212>] page_table_check_ptes_set include/linux/page_table_check.h:83 [inline]
[<ffffffff80c0b212>] set_ptes arch/riscv/include/asm/pgtable.h:635 [inline]
[<ffffffff80c0b212>] __split_huge_pmd_locked mm/huge_memory.c:3300 [inline]
[<ffffffff80c0b212>] split_huge_pmd_locked+0x1eba/0x23dc mm/huge_memory.c:3318
[<ffffffff80c0b9de>] __split_huge_pmd+0x2aa/0x3d4 mm/huge_memory.c:3332
[<ffffffff80a80c4e>] move_page_tables+0x9f6/0x3cc8 mm/mremap.c:858
[<ffffffff80a84156>] copy_vma_and_data+0x236/0x694 mm/mremap.c:1282
[<ffffffff80a84ab4>] move_vma+0x500/0x16d8 mm/mremap.c:1362
[<ffffffff80a85ea8>] mremap_to+0x21c/0x474 mm/mremap.c:1486
[<ffffffff80a867f6>] remap_move mm/mremap.c:1943 [inline]
[<ffffffff80a867f6>] do_mremap mm/mremap.c:1991 [inline]
[<ffffffff80a867f6>] __do_sys_mremap+0x6f6/0x16c8 mm/mremap.c:2055
[<ffffffff80a87868>] __se_sys_mremap mm/mremap.c:2023 [inline]
[<ffffffff80a87868>] __riscv_sys_mremap+0xa0/0x124 mm/mremap.c:2023
[<ffffffff80078f96>] syscall_handler+0x92/0x114 arch/riscv/include/asm/syscall.h:112
[<ffffffff864f95a4>] do_trap_ecall_u+0x3e4/0x638 arch/riscv/kernel/traps.c:342
[<ffffffff86525518>] handle_exception+0x168/0x174 arch/riscv/kernel/entry.S:237
Code: d097 ff8a 80e7 4f20 83e3 e004 e097 ff8a 80e7 9f20 (9002) e097 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	ff8ad097          	auipc	ra,0xff8ad
   4:	4f2080e7          	jalr	1266(ra) # 0xff8ad4f2
   8:	e00483e3          	beqz	s1,0xfffffffffffffe0e
   c:	ff8ae097          	auipc	ra,0xff8ae
  10:	9f2080e7          	jalr	-1550(ra) # 0xff8ad9fe
* 14:	9002                	ebreak <-- trapping instruction
  16:	97e0                	.short	0xe097