[BUG] none-initialized pagetable data

[evolution124]

Description / Steps to reproduce the issue

1. run qemu with backend file to simulate ram with random initialized ram data.
2. mmu pagetable in linker script is NONLOAD
3. mmu qemu_rv_kernel_mappings dose not initialize pagetable with initial value (like zero)
4. when mmu find initialized mapping, will use none-initialized value which cause error.

static void map_region(uintptr_t paddr, uintptr_t vaddr, size_t size, uint32_t mmuflags)
{
  uintptr_t alignaddr;
  uintptr_t endaddr;
  uintptr_t pbase;

  endaddr = vaddr + size;
 
  while (vaddr < endaddr)
    {
      /* See if a mapping exists ? */
      /* mmu_ln_getentry will get un initialized value */
      pbase = mmu_pte_to_paddr(mmu_ln_getentry(
                 KMM_SPBASE_IDX, KMM_SPBASE, vaddr));

On which OS does this issue occur?

[OS: Windows], [OS: Linux]

What is the version of your OS?

Ubuntu 24.04

NuttX Version

96f440f0c068f278cc11a956c2c6cf52ff79cf01

Issue Architecture

[Arch: risc-v]

Issue Area

[Area: Memory Management], [Area: Board support]

Host information

qemu to run the rv64
qemu-system-riscv64 --version
QEMU emulator version 10.0.0

Verification

• I have verified before submitting the report.