The action of Accessed and Dirty bit for EPT

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi there,

I write a piece of code to test the action of Accessed and Dirty bit
of EPT in Intel(R) Core(TM) i3-4130 CPU @ 3.40GHz. Firstly I build a
totally new EPT paging structure with A/D logging on, then run some
operating system codes and log all the EPT violation (say trap log).
At some point I paused the OS, parse the EPT paging structure and log
all the entries built in the past period (say A/D log).

Here I get some interesting points:

1. Some EPT entries are built without either Accessed or Dirty bit
set, does this mean that CPU only construct these entries but doesn't
touch them?
2. Some entries only exist in A/D log. Does A/D logging module has
some bias or some mistake?

These two logs (trap log and A/D log) should be the same according to
my understanding, and when I tried in the previous CPU without A/D bit
supporting, these two logs are exactly the same, though I just parse
the EPT paging structure and cannot distinguish Accessed or Dirty in
it.


Thanks ahead,

Arthur


-- 
Arthur Chunqi Li
Department of Computer Science
School of EECS
Peking University
Beijing, China
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux