On 2011?10?14? 03:07, Pasi Kärkkäinen wrote:
> On Thu, Oct 13, 2011 at 11:51:01PM +0800, Zhengwang Ruan (Royo) wrote:
>> Hi Guys,
>>
> Hello,
>
>> I am new man with some confusions to this amazing technology, hope you
>> guys give answers to help me better understand Xen. :)
>>
> Maybe this wiki page gives some general info about Xen:
> http://wiki.xen.org/xenwiki/XenOverview
>
>
> And these PDFs:
> http://xen.org/files/Marketing/WhatisXen.pdf
> http://xen.org/files/Marketing/WhyXen.pdf
>
>
>> 1, You guys have been working on developing many releases, do you guys
>> have agreements on developing every source code based on a fixed linux
>> kernel version before starting a new release? If so, how could I know
>> the corresponding kernel version to a given xen release? I tried to find
>> answer for myself on the following wiki page, but it is not latest
>> enough.
>>
> Are you talking about dom0 kernel? or domU kernel?
>
> Xen hypervisor (xen.gz) is the compatibility layer,
> so dom0 and domUs (VMs) can all have different Linux kernel versions.

Hi Pasi,


I refer to dom0 here. I got many details on wiki 
http://wiki.xen.org/xenwiki/XenParavirtOps , it helps me understand some.

 From this page, I know you guys developed xen-3.x based on 
linux-2.6.18, and and xen-4.x on 2.6.32, am I right? So these two 
versions of kernel should be supported mostly, right?

For domU, each kernel from kernel.org should be working as a guest?


<http://wiki.xen.org/xenwiki/XenParavirtOps>
>> http://wiki.xen.org/xenwiki/DistributionSupport
>>
>> 2, I found some interesting source files in xen-4.1.1 release, I listed
>> them below:
>>
>> $ ll
>> drwx------ 4 royo royo 16384 2011-10-12 00:20 arch/
>> drwx------ 5 royo royo 16384 2011-06-15 00:03 common/
>> -rw-r--r-- 1 royo royo 19185 2011-06-15 00:03 COPYING
>> drwx------ 2 royo royo 16384 2011-06-15 00:03 crypto/
>> drwx------ 8 royo royo 16384 2011-06-15 00:03 drivers/
>> drwx------ 9 royo royo 16384 2011-06-15 00:03 include/
>> -rw-r--r-- 1 royo royo  5529 2011-06-15 00:03 Makefile
>> -rw-r--r-- 1 royo royo  3498 2011-06-15 00:03 Rules.mk
>> drwx------ 3 royo royo 16384 2011-06-15 00:03 tools/
>> drwx------ 4 royo royo 16384 2011-06-15 00:03 xsm/
>>
>> Are these files going to replace or be added to linux kernel source
>> while making dm0? I am amazed that this release can be installed to many
>> linux distributions with different kernel, how could you guys achieve
>> this?
>>
> Xen hypervisor (xen.gz) is a totally separate binary, it's not "mixed" to/with Linux kernel.

And, xen-4.1.1 is compiled to generate xen.gz which is started by dom0 
and running on/inside dom0 as Hypervisor?

> - For Xen dom0 you need to use a Linux kernel that has Xen dom0 support enabled.
> - For Xen PV domUs (VMs) you need to use a Linux kernel that has Xen PV domU support enabled.
> - For Xen HVM VMs you don't need a special kernel, but having Xen PVHVM drivers in the kernel will boost disk/net

PVHVM drivers are implemented using xenbus? The drivers in xenbus/ 
directory are you called PVHVM drivers?

Thanks,
Royo

> performance.
>
> Xen related features in different Linux kernel versions:
> http://wiki.xen.org/xenwiki/XenParavirtOps
>
>
> -- Pasi
>