H20 paging-multilevel-translate example

https://www.ece.villanova.edu/os/cgi/paging-multilevel-translate?+1

https://www.ece.villanova.edu/os/cgi/paging-multilevel-translate?+1+ans (with answers)

seed = 1 

PDBR: 0x11

>>> va = 0x6c75 # split into three 5-bit pieces:

>>> hex(va>>10), hex((va>>5) & 0x1f), hex(va & 0x1f)

('0x1b', '0x3', '0x15')  # PDE index = 0x1b, PTE index = 0x3, PA offset = 0x15

# at page 0x11, offset 0x1b: a0

>>> hex(0xa0 & 0x7f)     # PDE contents = 0xa0, valid, PT page = 0x20

'0x20'

# at page 0x20, offset 0x3: e1

>>> hex(0xe1 & 0x7f)     # PTE contents = 0xe1, valid, PFN = 0x61

'0x61'

# at page 0x61, offset 0x15: 0d

>>> hex((0x61<<5) | 0x15) # PA = page 0x61, offset 0x15

'0xc35'

>>>