Kernel: Don't truncate physical memory space PDE pointers

For some odd reason we used to return PhysicalPtr for a page_table_base
result, but when setting it we accepted only a 32 bit value, so we
truncated valid 64 bit addresses into 32 bit addresses by doing that.
With this commit being applied, now PageDirectories can be located
beyond the 4 GiB barrier.

This was found by sin-ack, therefore he should be credited with this fix
appropriately with Co-authored-by sign.

Co-authored-by: sin-ack <sin-ack@users.noreply.github.com>
This commit is contained in:
Liav A 2022-10-08 02:08:03 +03:00 committed by Andrew Kaster
parent 9cbae2b607
commit f07e0180d6
2 changed files with 2 additions and 2 deletions

View file

@ -38,7 +38,7 @@ constexpr u32 DEVICE_MEMORY = (1 << 2);
class PageDirectoryEntry {
public:
PhysicalPtr page_table_base() const { return PhysicalAddress::physical_page_base(m_raw); }
void set_page_table_base(u32 value)
void set_page_table_base(PhysicalPtr value)
{
m_raw &= 0xffff000000000fffULL;
m_raw |= PhysicalAddress::physical_page_base(value);

View file

@ -16,7 +16,7 @@ namespace Kernel {
class PageDirectoryEntry {
public:
PhysicalPtr page_table_base() const { return PhysicalAddress::physical_page_base(m_raw); }
void set_page_table_base(u32 value)
void set_page_table_base(PhysicalPtr value)
{
m_raw &= 0x8000000000000fffULL;
m_raw |= PhysicalAddress::physical_page_base(value);