diff --git a/tests/unit/test_x86.c b/tests/unit/test_x86.c
index 17624c86..41830e4b 100644
--- a/tests/unit/test_x86.c
+++ b/tests/unit/test_x86.c
@@ -1489,7 +1489,9 @@ static void test_x86_mmu_prepare_tlb(uc_engine *uc, uint64_t vaddr,
     OK(uc_mem_write(uc, tlb_base + pml4o, &pml4e_mem, sizeof(pml4o)));
     OK(uc_mem_write(uc, tlb_base + 0x1000 + pdpo, &pdpe_mem, sizeof(pdpe)));
     OK(uc_mem_write(uc, tlb_base + 0x2000 + pdo, &pde_mem, sizeof(pde)));
-    OK(uc_reg_write(uc, UC_X86_REG_CR3, &tlb_base));
+    uint32_t cr3 = tlb_base & 0xFFFFFFFF;
+    cr3 = LEINT32(cr3);
+    OK(uc_reg_write(uc, UC_X86_REG_CR3, &cr3));
     OK(uc_reg_read(uc, UC_X86_REG_CR0, &cr0));
     OK(uc_reg_read(uc, UC_X86_REG_CR4, &cr4));
     OK(uc_reg_read(uc, UC_X86_REG_MSR, &msr));