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: 3956 Comm: syz.1.27 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 : ffffffff80c4d33e ra : ffffffff80c4d33e sp : ffff8f800aae6fd0
 gp : ffffffff8a2739c0 tp : ffffaf801af14f80 t0 : ffffaf80191758a0
 t1 : fffff5ef02728009 t2 : ffffffff80a6d720 s0 : ffff8f800aae7050
 s1 : 0000000000000001 a0 : 0000000000000001 a1 : 0000000000000000
 a2 : 0000000000080000 a3 : ffffffff80c4d33e a4 : ffff8f80051a95a0
 a5 : 00000000000bc5a0 a6 : 0000000000000003 a7 : ffffaf801394004b
 s2 : 00000000000b4000 s3 : 0000000000000000 s4 : ffffaf8013940000
 s5 : 0000000000000200 s6 : 0000000000000001 s7 : dfffffff00000000
 s8 : 0000000000007fff s9 : ffffffff88a4b000 s10: 0000000000000000
 s11: ffffffff8a390be0 t3 : 0000000000000001 t4 : fffff5ef02728009
 t5 : fffff5ef0272800a t6 : 0000000000000002 ssp : 0000000000000000
status: 0000000200000120 badaddr: ffffffff80c4d33e cause: 0000000000000003
[<ffffffff80c4d33e>] page_table_check_set+0x996/0xc38 mm/page_table_check.c:118
[<ffffffff80c4daa8>] __page_table_check_ptes_set+0x264/0x47c mm/page_table_check.c:212
[<ffffffff80bd8f06>] page_table_check_ptes_set include/linux/page_table_check.h:83 [inline]
[<ffffffff80bd8f06>] set_ptes arch/riscv/include/asm/pgtable.h:625 [inline]
[<ffffffff80bd8f06>] __split_huge_pmd_locked mm/huge_memory.c:3358 [inline]
[<ffffffff80bd8f06>] split_huge_pmd_locked+0x1e2a/0x2388 mm/huge_memory.c:3376
[<ffffffff80bd970e>] __split_huge_pmd+0x2aa/0x3d4 mm/huge_memory.c:3390
[<ffffffff80a52ad6>] move_page_tables+0x986/0x3ce0 mm/mremap.c:858
[<ffffffff80a56066>] copy_vma_and_data+0x236/0x694 mm/mremap.c:1282
[<ffffffff80a569c4>] move_vma+0x500/0x16d8 mm/mremap.c:1362
[<ffffffff80a57db8>] mremap_to+0x21c/0x474 mm/mremap.c:1486
[<ffffffff80a58a02>] do_mremap mm/mremap.c:1999 [inline]
[<ffffffff80a58a02>] __do_sys_mremap+0x9f2/0x16d0 mm/mremap.c:2055
[<ffffffff80a59780>] __se_sys_mremap mm/mremap.c:2023 [inline]
[<ffffffff80a59780>] __riscv_sys_mremap+0xa0/0x124 mm/mremap.c:2023
[<ffffffff80078f3a>] syscall_handler+0x92/0x114 arch/riscv/include/asm/syscall.h:112
[<ffffffff86469874>] do_trap_ecall_u+0x3e4/0x638 arch/riscv/kernel/traps.c:342
[<ffffffff86494eb0>] handle_exception+0x168/0x174 arch/riscv/kernel/entry.S:232
Code: 1097 ff8d 80e7 8be0 83e3 e004 1097 ff8d 80e7 d920 (9002) 1097 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	ff8d1097          	auipc	ra,0xff8d1
   4:	8be080e7          	jalr	-1858(ra) # 0xff8d08be
   8:	e00483e3          	beqz	s1,0xfffffffffffffe0e
   c:	ff8d1097          	auipc	ra,0xff8d1
  10:	d92080e7          	jalr	-622(ra) # 0xff8d0d9e
* 14:	9002                	ebreak <-- trapping instruction
  16:	9710                	.short	0x1097