syzbot

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kernel BUG at [] mm/page_table_check.c:142!
Kernel BUG [#1]
Modules linked in:
CPU: 0 UID: 0 PID: 5540 Comm: syz.3.237 Not tainted syzkaller #0 PREEMPT 
Hardware name: riscv-virtio,qemu (DT)
epc : __page_table_check_zero+0x396/0x544 mm/page_table_check.c:142
 ra : __page_table_check_zero+0x396/0x544 mm/page_table_check.c:142
epc : ffffffff80bfdcce ra : ffffffff80bfdcce sp : ffff8f800a166b00
 gp : ffffffff89f9df20 tp : ffffaf8013b10000 t0 : ffffffff80ab6042
 t1 : fffff5ef02705013 t2 : ffffffff80b91ae2 s0 : ffff8f800a166b70
 s1 : ffffaf8013828098 a0 : 0000000000000005 a1 : 0000000000000000
 a2 : 0000000000080000 a3 : ffffffff80bfdcce a4 : ffff8f800527c000
 a5 : 0000000000080000 a6 : 0000000000000003 a7 : ffffaf801382809b
 s2 : 0000000000000001 s3 : 0000000000000000 s4 : ffffaf8013828050
 s5 : dfffffff00000000 s6 : 00000000000b8801 s7 : 0000000000000001
 s8 : 0000000000000000 s9 : 0000000000007fff s10: fffffffef1416bb0
 s11: ffffffff8a0b5d80 t3 : 0000000000000001 t4 : fffff5ef02705013
 t5 : fffff5ef02705014 t6 : 0000000000000002 ssp : 0000000000000000
status: 0000000200000120 badaddr: ffffffff80bfdcce cause: 0000000000000003
[<ffffffff80bfdcce>] __page_table_check_zero+0x396/0x544 mm/page_table_check.c:142
[<ffffffff80a6f0d6>] page_table_check_free include/linux/page_table_check.h:43 [inline]
[<ffffffff80a6f0d6>] free_pages_prepare mm/page_alloc.c:1434 [inline]
[<ffffffff80a6f0d6>] __free_frozen_pages+0x7e6/0x1480 mm/page_alloc.c:2973
[<ffffffff80a76b8a>] free_frozen_pages+0xe/0x18 mm/page_alloc.c:3011
[<ffffffff808ab912>] __folio_put+0x296/0x378 mm/swap.c:112
[<ffffffff80ac4a14>] folio_put include/linux/mm.h:1617 [inline]
[<ffffffff80ac4a14>] free_folio_and_swap_cache+0x100/0x13c mm/swap_state.c:332
[<ffffffff80b90fda>] __folio_split+0x10ce/0x16f8 mm/huge_memory.c:4088
[<ffffffff80b91ae2>] __split_huge_page_to_list_to_order+0x7e/0x140 mm/huge_memory.c:4200
[<ffffffff80b9554a>] split_huge_page_to_list_to_order include/linux/huge_mm.h:385 [inline]
[<ffffffff80b9554a>] split_folio_to_list+0x22/0x30 mm/huge_memory.c:4264
[<ffffffff80ab469a>] madvise_cold_or_pageout_pte_range+0x1862/0x2400 mm/madvise.c:412
[<ffffffff80a03002>] walk_pmd_range mm/pagewalk.c:130 [inline]
[<ffffffff80a03002>] walk_pud_range mm/pagewalk.c:224 [inline]
[<ffffffff80a03002>] walk_p4d_range mm/pagewalk.c:262 [inline]
[<ffffffff80a03002>] walk_pgd_range+0xcc6/0x1f84 mm/pagewalk.c:303
[<ffffffff80a043f8>] __walk_page_range+0x138/0x7a8 mm/pagewalk.c:410
[<ffffffff80a05cf2>] walk_page_range_vma_unsafe+0x212/0x868 mm/pagewalk.c:714
[<ffffffff80a063a2>] walk_page_range_vma+0x5a/0x84 mm/pagewalk.c:724
[<ffffffff80aaf14e>] madvise_pageout_page_range mm/madvise.c:622 [inline]
[<ffffffff80aaf14e>] madvise_pageout+0x236/0x794 mm/madvise.c:647
[<ffffffff80ab6042>] madvise_vma_behavior+0xb0a/0x251c mm/madvise.c:1366
[<ffffffff80ab7c8e>] madvise_walk_vmas+0x23a/0x970 mm/madvise.c:1721
[<ffffffff80ab85ae>] madvise_do_behavior+0x1ea/0x5c0 mm/madvise.c:1937
[<ffffffff80ab94c6>] do_madvise+0x18a/0x22c mm/madvise.c:2030
[<ffffffff80ab95f0>] __do_sys_madvise mm/madvise.c:2039 [inline]
[<ffffffff80ab95f0>] __se_sys_madvise mm/madvise.c:2037 [inline]
[<ffffffff80ab95f0>] __riscv_sys_madvise+0x88/0xdc mm/madvise.c:2037
[<ffffffff80078192>] syscall_handler+0x92/0x114 arch/riscv/include/asm/syscall.h:112
[<ffffffff86391c0a>] do_trap_ecall_u+0x3d2/0x58c arch/riscv/kernel/traps.c:344
[<ffffffff863bb61e>] handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232
Code: 7f80 8526 c0ef ec3f 8a2a b791 6097 ff90 80e7 7e60 (9002) 6097 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	7f80                	flw	fs0,56(a5)
   2:	8526                	mv	a0,s1
   4:	ec3fc0ef          	jal	0xffffffffffffcec6
   8:	8a2a                	mv	s4,a0
   a:	b791                	j	0xffffffffffffff4e
   c:	ff906097          	auipc	ra,0xff906
  10:	7e6080e7          	jalr	2022(ra) # 0xff9067f2
* 14:	9002                	ebreak <-- trapping instruction
  16:	9760                	.short	0x6097