Re: mmap in PV xen-4.0.1

[Eric Camachat <eric.camachat@gmail.com>]

On Wed, Aug 10, 2011 at 8:10 PM, Eric Camachat <eric.camachat@gmail.com> wrote:
> On Wed, Aug 10, 2011 at 6:31 PM, Wei Liu <liuw@liuw.name> wrote:
>> On Wed, Aug 10, 2011 at 12:45:20PM -0700, Eric Camachat wrote:
>>> The idea is move servers into XEN domU.
>>> I saw that 3.0 has built-in XEN support, I can try it later.
>>> But I don't know if other components are compatible with 3.0.
>>>
>>> I just wonder that MFN should equals PFN in PV (para-virtualization),
>>> so it should works properly.
>>>
>>
>> If by "PFN" you mean "Physical Frame Number", then I think you made a
>> wrong assumption here.
>>
>> MFN and PFN has no linear, 1:1 mapping relationship, let alone say
>> they are equal.
>>
>> Wei.
>>
> I misunderstood in GFN and PFN, MFN and GFN should be equal.
> So PV domU has the same memory view with real hardware, right?
>
> Ref. http://blog.xen.org/index.php/2009/10/09/xen-memory-management-overview-presentation/
>

Let us back to my original concern:
Why remap_pfn_range() woks with my own device node, but deesn't work
with /dev/mem node?
This behavior is confused me.

/Eric