Yu Zhang,

As we discussed, attached is the draft of the change to the p2m_change_entry_type changes I was working on.

Currently, Xen keeps track of what certain types “should” be, via a list of logdirty ranges as well as mmio ranges. 

This patch series attempts to do the opposite: to make “p2m_change_entry_type” simply change all entries of type ot to type nt.

It has a couple of issues at the moment.  It’s not yet complete — the actual number of entries still to be recalculated isn’t counted.

At the moment both migration and vram logdirty are used by the same type, and disambiguated by the “global_logdirty” bit.  To move to the new model, we’d have to have two different types.

And some more listed in the patches.

As I said, I’m not sure this is the right way forward or not — but I think it’s worth looking at.

Peace,

 -George