tree ad93a1164173c611f6ac57481efa363ae6fdac64
parent 2cc42bac1c795f75fcc062b95c6ca7ac1b84d5d8
author Boris Ostrovsky <boris.ostrovsky@oracle.com> 1513109301 -0500
committer Boris Ostrovsky <boris.ostrovsky@oracle.com> 1513793780 -0500

xen/balloon: Mark unallocated host memory as UNUSABLE

Commit f5775e0b6116 ("x86/xen: discard RAM regions above the maximum
reservation") left host memory not assigned to dom0 as available for
memory hotplug.

Unfortunately this also meant that those regions could be used by
others. Specifically, commit fa564ad96366 ("x86/PCI: Enable a 64bit BAR
on AMD Family 15h (Models 00-1f, 30-3f, 60-7f)") may try to map those
addresses as MMIO.

To prevent this mark unallocated host memory as E820_TYPE_UNUSABLE (thus
effectively reverting f5775e0b6116) and keep track of that region as
a hostmem resource that can be used for the hotplug.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>