Kernel: Hand out 64-bit addresses to userspace

Kernel/Sections.h

@@ -24,4 +24,4 @@ extern "C" FlatPtr kernel_base;
 #define KERNEL_QUICKMAP_PD (KERNEL_PT1024_BASE + 0x7000)
 #define KERNEL_QUICKMAP_PER_CPU_BASE (KERNEL_PT1024_BASE + 0x8000)
 
-#define USER_RANGE_CEILING 0xBE000000
+#define USER_RANGE_CEILING (kernel_base - 0x2000000)

Kernel/VM/PageDirectory.cpp

@@ -69,7 +69,7 @@ UNMAP_AFTER_INIT void PageDirectory::allocate_kernel_directory()
 PageDirectory::PageDirectory(const RangeAllocator* parent_range_allocator)
 {
     constexpr FlatPtr userspace_range_base = 0x00800000;
-    constexpr FlatPtr userspace_range_ceiling = USER_RANGE_CEILING;
+    FlatPtr userspace_range_ceiling = USER_RANGE_CEILING;
 
     ScopedSpinLock lock(s_mm_lock);
     if (parent_range_allocator) {