Re: [PATCH v11 6/9] xen: Add ring 3 vmware_port support

[Don Slutz <dslutz@verizon.com>]

On 06/12/15 02:25, Jan Beulich wrote:
>>>> On 12.06.15 at 00:10, <dslutz@verizon.com> wrote:
>> On 06/05/15 06:54, Ian Campbell wrote:
>>> It would be really useful to see a comprehensive list of exactly what
>>> guest ring3 access to the vmware port actually enables i.e. a list of
>>> specific features which require it.
>>
>> Ok, I have done some testing.  Here is what I know:
>>
>> Without ring3 support:
>>
>> 1) VMware tools will not install on linux and windows.
>> 2) open-vm-tools (https://github.com/vmware/open-vm-tools) will not
>> install (how ever it is not hard to change it to do so, you need to add
>> a call to iopl(3) need to be added in a few places) on linux
>>
>> However if VMware tools did get installed on the window disk bits
>> somehow, the VMware mouse support works.  Linux gets this because Xorg
>> detects and uses the VMware mouse under IOPL(3).
> 
> Now that tells us that the tools may not work, but not what
> implications that has on the usability of the VM once migrated
> to Xen. Them not installing is a non-issue afaict, since after
> having moved the VM to Xen there shouldn't be a need to
> install them anymore - either they've been there, or I don't
> see why they would be needed _after_ the move. And you
> say that the mouse works in both cases if the tools happen
> to be there.
> 

The VMware tools service will start but does not work.  It adds to the
event log:

[warning][vmusr:vmtoolsd] The vmuser service needs to run inside a
virtual machine.

And the available features of VMware tools is disabled:

   1) The ability to perform virtual machine power operations gracefully
is missing. (code to access QEMU's from Xen to do this is  missing).
I.E. get windows to shutdown when requested!

   2) Execution of VMware provided or user configured scripts in guests
during various power operations.

   3) Clock synchronization between guests and hosts or client desktops.

   4) Access to VMware guest info variables (code to access QEMU's from
Xen to do this is missing).  This can be used to customize guest
operating systems immediately after powering on virtual machines. It can
also be used to monitor the health of a guest.


The reason to install them after is to get the VMware mouse driver on
Windows.  This mouse driver works much better on Window when there is
higher network latency.

   -Don Slutz

> Jan
>