[CentOS-virt] Centos 7 newer kernel needed

-=X.L.O.R.D=-
2016-08-05T05:32:20Z

Dear Laurentiu,
Agree with Johnny for kernel upgrade if upgrade helps, alternative if 3.10
or above already supported it, you can check from kernel parameter or
options if they are disabled on purpose.
You can do that via the "make menuconfig" via
"https://wiki.centos.org/HowTos/I_need_the_Kernel_Source" or
"https://wiki.centos.org/HowTos/BuildingKernelModules". Hope that
helps!

Xlord
-----Original Message-----
From: centos-virt-bounces at centos.org [mailto:centos-virt-bounces at
centos.org]
On Behalf Of Johnny Hughes
Sent: Thursday, August 4, 2016 9:10 PM
To: centos-virt at centos.org
Subject: Re: [CentOS-virt] Centos 7 newer kernel needed

On 08/04/2016 07:30 AM, Laurentiu Soica wrote:
> Hi Xlord,
>
> Yes,  the CPU has support for EPT.
>
> I wrongly thought that the nested EPT was first introduced in 3.12.
> Following your instructions I see that I have it enabled on my system
> as well.
>
> However,  checking the kernel commits from 3.12 on search string
> 'nested ept'  I found about 10 code changes/fixes for nested EPT.
>
> https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/l
> og/?id=refs%2Ftags%2Fv3.12.62&qt=grep&q=Nested+ept
>
> What options do I have to get this commits on a Centos 7 kernel?

The Standard CentOS kernel is built from the source code and configuration
files of the released RHEL kernel.  The only way to get things into the main
CentOS kernel is for it to be in the RHEL source code.

Red Hat does backport changes into the RHEL kernel, so if they support
nested those changes or ones like it may be there.  See Backporting:

https://access.redhat.com/security/updates/backporting

We do have a CentOSPlus kernel, maintained by a volunteer (hi toracat).
She will take potential patches here if you have something that works:

https://bugs.centos.org/view.php?id=6828

Also, if you want to try a newer kernel, we do have 2 available.  I manage
both of these kernels, they are both based on an LTS version of the kernel
from kernel.org .. but neither gets nearly the attention (or smart people
looking at them) as the RHEL based kernel.  If you want to try either of
them, they are in:

3.18.x LTS:
http://mirror.centos.org/centos/7/virt/x86_64/xen-46/

4.4.x LTS:
http://mirror.centos.org/altarch/7.2.1511/experimental/x86_64/Packages/

Those kernels both work, I am running both on production machines .. but I
am not a kernel hacker, so I just build what the upstream LTS kernel
maintainer releases.  They may or may not do what you want.

The RHEL kernel team does a lot of work to make sure the RHEL kernel

Thanks,
Johnny Hughes