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: 7014 Comm: syz.2.519 Tainted: G        W    L      syzkaller #0 PREEMPT 
Tainted: [W]=WARN, [L]=SOFTLOCKUP
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 : ffff8f80022e61d0
 gp : ffffffff8a49d240 tp : ffffaf801cd81ac0 t0 : 0000000000000000
 t1 : fffff5ef02800009 t2 : ffffffff91874220 s0 : ffff8f80022e6250
 s1 : 0000000000000001 a0 : 0000000000000001 a1 : 0000000000000000
 a2 : 0000000000080000 a3 : ffffffff80c8200a a4 : ffff8f800b9d3e60
 a5 : 00000000000c9e60 a6 : 0000000000000003 a7 : ffffaf801400004b
 s2 : 00000000000b8000 s3 : 0000000000000000 s4 : ffffaf8014000000
 s5 : 0000000000000001 s6 : 0000000000000001 s7 : dfffffff00000000
 s8 : 0000000000007fff s9 : ffffffff88c5a000 s10: 0000000000000000
 s11: ffffffff8a5bbca0 t3 : 0000000000000001 t4 : fffff5ef02800009
 t5 : fffff5ef0280000a 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
[<ffffffff80be740c>] page_table_check_ptes_set include/linux/page_table_check.h:83 [inline]
[<ffffffff80be740c>] set_ptes arch/riscv/include/asm/pgtable.h:635 [inline]
[<ffffffff80be740c>] remove_migration_pte+0x1038/0x213c mm/migrate.c:436
[<ffffffff80a96e46>] rmap_walk_anon+0x30e/0x690 mm/rmap.c:3001
[<ffffffff80aafb4a>] rmap_walk_locked+0xa6/0xcc mm/rmap.c:3117
[<ffffffff80bf0e8a>] remove_migration_ptes+0x18a/0x1bc mm/migrate.c:471
[<ffffffff80c0fd60>] remap_page mm/huge_memory.c:3482 [inline]
[<ffffffff80c0fd60>] __folio_split+0xce8/0x1410 mm/huge_memory.c:4110
[<ffffffff80c13a00>] __split_huge_page_to_list_to_order mm/huge_memory.c:4240 [inline]
[<ffffffff80c13a00>] split_huge_page_to_list_to_order include/linux/huge_mm.h:415 [inline]
[<ffffffff80c13a00>] split_folio_to_list+0x4c/0x60 mm/huge_memory.c:4304
[<ffffffff80965754>] shrink_folio_list+0x21d8/0x4d90 mm/vmscan.c:1284
[<ffffffff80968440>] reclaim_folio_list+0x134/0x8f0 mm/vmscan.c:2171
[<ffffffff80977a1e>] reclaim_pages+0x33e/0x4b8 mm/vmscan.c:2208
[<ffffffff80b3d960>] madvise_cold_or_pageout_pte_range+0x1b40/0x236c mm/madvise.c:444
[<ffffffff80a8cbf2>] walk_pmd_range mm/pagewalk.c:148 [inline]
[<ffffffff80a8cbf2>] walk_pud_range mm/pagewalk.c:239 [inline]
[<ffffffff80a8cbf2>] walk_p4d_range mm/pagewalk.c:280 [inline]
[<ffffffff80a8cbf2>] walk_pgd_range+0xd12/0x1ecc mm/pagewalk.c:321
[<ffffffff80a8dee4>] __walk_page_range+0x138/0x7a8 mm/pagewalk.c:429
[<ffffffff80a8f718>] walk_page_range_vma_unsafe+0x1ec/0x82c mm/pagewalk.c:733
[<ffffffff80a8fdb2>] walk_page_range_vma+0x5a/0x84 mm/pagewalk.c:743
[<ffffffff80b37afa>] madvise_pageout_page_range mm/madvise.c:622 [inline]
[<ffffffff80b37afa>] madvise_pageout+0x236/0x780 mm/madvise.c:647
[<ffffffff80b3f4f4>] madvise_vma_behavior+0x72c/0x1eb0 mm/madvise.c:1358
[<ffffffff80b40eb2>] madvise_walk_vmas+0x23a/0x978 mm/madvise.c:1713
[<ffffffff80b417da>] madvise_do_behavior+0x1ea/0x5c0 mm/madvise.c:1908
[<ffffffff80b42aba>] do_madvise+0x23a/0x294 mm/madvise.c:2006
[<ffffffff80b42b9c>] __do_sys_madvise mm/madvise.c:2015 [inline]
[<ffffffff80b42b9c>] __se_sys_madvise mm/madvise.c:2013 [inline]
[<ffffffff80b42b9c>] __riscv_sys_madvise+0x88/0xdc mm/madvise.c:2013
[<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