Author Topic: request privilege level check  (Read 4169 times)

Offline junior_study

  • Jr. Member
  • *
  • Posts: 4
request privilege level check
« on: July 20, 2012, 02:16:36 PM »
hi,
  when I  access a memory page,  what  is  the  procedure  of  RPL check?
  cpu will  compare what with the segment's  RPL ?

thank you!

Offline yangbowen1

  • Jr. Member
  • *
  • Posts: 4
Re: request privilege level check
« Reply #1 on: August 21, 2012, 08:43:17 AM »
RPL is specified in the selector INSTEAD OF THE SEGMENT DESCRIPTOR.CPU will check if RPL>=CPL and RPL<=DPL (For data segments). Note that CPL is "current privilege level" and DPL is "descriptor privilege level".
See also: http://www.intel.com/content/www/us/en/processors/architectures-software-developer-manuals.html
Volume 3, Chapter 5 Protection
« Last Edit: August 21, 2012, 08:46:48 AM by yangbowen1 »