Virtual Memory Map

[Damian Tometzki]

Hello all,

i have a short question:

How are the bits (in brackets) calculated in the virtual memory map ?

for example the first line (=47 bits)

Virtual memory map with 4 level page tables:

0000000000000000 - 00007fffffffffff (=47 bits) user space, different per mm
hole caused by [47:63] sign extension
ffff800000000000 - ffff87ffffffffff (=43 bits) guard hole, reserved for hypervisor

Best regards
Damian