Created attachment 146739 [details]
Enable shadow before memory reservation for HVM

It turns out that the bogus m2p entries are a recent introduction.  When
shadow2 (changeset 11151) was introduced, upstream moved the code that enables
shadow mode for HVM guests to user-space.  In particular, this was done after
memory allocation and before the physmap has been populated.  This only
affected HVM because PV translate mode populated the physmap before enabling
shadow mode.

Upstream has since fixed it by moving the enabling of shadow mode back into the
hypervisor which means that it will occur before memory allocation.  This patch
tries to do this in a more conservative way by simply moving the enabling of
shadow mode before memory allocation.

I've verified that running this version of xend allows me to start HVM guests
on a host where otherwise you can't start HVM guests at all due to this bug.

When we move to 3.0.4 we can remove the shadow_enable function from the python
bindings of libxc.

Created attachment 146761 [details]
[XEN]: Enable shadow before memory reservation for HVM

This version adds an HVM check so that we only enable shadow mode on HVM
guests.  The shadow_enable function is also renamed to hvm_shadow_enable.

QE ack for RHEL5.

Rik - Let's build the pacakge and the version number in the BZ.  If we decide to
include it in a respin, we can drag it in.

Brian

in 3.0.3-23.el5

Closing out.