Re: [Xen-users] Reading a DomU's memory from Dom0 or Xen hypervisor

[Roger Pau Monné <roger.pau@xxxxxxxxxx>]

On Thu, Oct 05, 2017 at 05:51:39PM +0000, Brett Stahlman wrote:
> I'd like to be able to read specific memory locations within a DomU,
> either by guest-physical or guest-virtual address, and I'm wondering
> what the Xen-provided options in this area are. I've seen
> documentation on "grant tables", but that mechanism seems tailored
> towards communication between front and back-end drivers. All I want
> to do is allow code in either Dom0 or the hypervisor itself to read
> specific memory ranges within a specific DomU. I notice there's a
> raw_copy_from_guest() function (guestcopy.c), which looks like it
> could be useful. However, the hardcoding of "current->domain" in the
> call to get_page_from_gva() leads me to suspect that it's intended for
> use only in a hypercall. Is there a standard way to read memory from
> an *arbitrary* guest, either using guest-physical or guest-virtual
> addresses? If so, is it possible to do it from Dom0 without modifying
> the Xen hypervisor?
> 
> Links to relevant documentation or example source code would be
> greatly appreciated...

AFAICT you want to take a look at the foreignmemory library. It allows
you to map DomU memory from Dom0 user-space [0].

Roger.

[0] 
http://xenbits.xen.org/gitweb/?p=xen.git;a=blob;f=tools/libs/foreignmemory/core.c

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxx
https://lists.xen.org/xen-users