From: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Date: Fri, 16 Jul 2010 03:25:17 +0000 (+0800)
Subject: KVM: MMU: fix page dirty tracking lost while sync page
X-Git-Tag: v2.6.36-rc1~580^2~4
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9ed5520dd3c9cb79c25f95fce9c57b87637d0fb7;p=pandora-kernel.git

KVM: MMU: fix page dirty tracking lost while sync page

In sync-page path, if spte.writable is changed, it will lose page dirty
tracking, for example:

assume spte.writable = 0 in a unsync-page, when it's synced, it map spte
to writable(that is spte.writable = 1), later guest write spte.gfn, it means
spte.gfn is dirty, then guest changed this mapping to read-only, after it's
synced,  spte.writable = 0

So, when host release the spte, it detect spte.writable = 0 and not mark page
dirty

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---

Reading git-diff-tree failed