tree c023f7f31f3a3f6dd9f70942f8032dc077d1aa30
parent 26840437cbd6d3625ea6ab34e17cd34bb810c861
author Vitaly Kuznetsov <vkuznets@redhat.com> 1472080989 -0700
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1472641541 +0200

Drivers: hv: balloon: keep track of where ha_region starts

Windows 2012 (non-R2) does not specify hot add region in hot add requests
and the logic in hot_add_req() is trying to find a 128Mb-aligned region
covering the request. It may also happen that host's requests are not 128Mb
aligned and the created ha_region will start before the first specified
PFN. We can't online these non-present pages but we don't remember the real
start of the region.

This is a regression introduced by the commit 5abbbb75d733 ("Drivers: hv:
hv_balloon: don't lose memory when onlining order is not natural"). While
the idea of keeping the 'moving window' was wrong (as there is no guarantee
that hot add requests come ordered) we should still keep track of
covered_start_pfn. This is not a revert, the logic is different.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>