5 ms·
But x86-64 divides the 48-bit address space into two halves, only one of which is available in the user mode.
by lifthrasiir 7y ago
But x86-64 divides the 48-bit address space into two halves, only one of which is available in the user mode.
- monocasa 7y agoTo be fair, there's nothing that says the higher half _has_ to be entirely kernel mode. Only that bits 63 through 48 have to be the same value. And Intel has a spec out for a PML5 page table, giving you 57 total virtual address bits.