libvirt should enable pae setting for Xen or KVM guest

[Yufang Zhang]

Currently, nova doesn't enable pae setting for Xen or KVM guest in its libvirt driver. Windows(Win7 in my enviroment) guests would not boot successful in such case. This patch adds pae setting in libvirt driver for Xen or KVM guest, which would fix this problem.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/19908

[Daniel Berrange (berrange)]

What architecture are you using on the host and/or guest ? I'm guessing one, or both, of them must be 32-bit because the 'pae' flag is implied on x86_64 by virtue of it having 64-bit addressing

[Joe Gordon (jogo)]

patch was abandoned, unclear if this bug is still valid. Moving back to new for re-triage

[Alvaro Lopez (aloga)]

Hi Joe.

This is still valid. We have found that a HVM Windows 64 bit won't boot without PAE enabled (being the nova-compute server also 64 bit).

I will try to submit a new patch.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/110633

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/110633
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=dbb7ef845f5684673b320d0914d4f9cea12fef65
Submitter: Jenkins
Branch: master

commit dbb7ef845f5684673b320d0914d4f9cea12fef65
Author: Alvaro Lopez Garcia <email address hidden>
Date: Thu May 29 13:07:36 2014 +0200

    libvirt: set pae for Xen PVM and HVM

    The Physical Address Extension (PAE) enables paging to produce physical
    addresses with more that 32 bit (2^32 bytes, 4 GBytes), namely it
    extends the physical address space to 64 GBytes (2^36 bytes).

    When spawning a 32 bit image in Xen PVM or HVM, PAE should be enabled in the
    hypervisor so as to ensure that it is able to run properly. According to
    the Xen documentation it can be enabled safely: "In general you should
    leave this enabled and allow the guest Operating System to choose whether
    or not to use PAE. " [1]

    [1] http://xenbits.xen.org/docs/unstable/man/xl.cfg.5.html#pae_boolean

    Closes-Bug: #1100697
    Change-Id: If8d8ebc38efd969d96a1953446d72e72691734b3