[PATCH 2 of 9] x86/mm: Don't fail to nominate for paging on type flag, rather look at type count

[Andres Lagar-Cavilla <andres@lagarcavilla.org>]

 xen/arch/x86/mm/p2m.c |  4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)


Xen doesn't clean the type flag when dropping the type count for a page to
zero. So, looking at the type flag when nominating a page for paging it's
incorrect. Look at the type count instead.

Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Signed-off-by: Adin Scannell <adin@scannell.ca>

diff -r decd21170c2a -r 27031a8a4eff xen/arch/x86/mm/p2m.c
--- a/xen/arch/x86/mm/p2m.c
+++ b/xen/arch/x86/mm/p2m.c
@@ -761,7 +761,7 @@ int p2m_mem_paging_nominate(struct domai
          (1 | PGC_allocated) )
         goto out;
 
-    if ( (page->u.inuse.type_info & PGT_type_mask) != PGT_none )
+    if ( (page->u.inuse.type_info & PGT_count_mask) != 0 )
         goto out;
 
     /* Fix p2m entry */
@@ -823,7 +823,7 @@ int p2m_mem_paging_evict(struct domain *
          (2 | PGC_allocated) )
         goto out_put;
 
-    if ( (page->u.inuse.type_info & PGT_type_mask) != PGT_none )
+    if ( (page->u.inuse.type_info & PGT_count_mask) != 0 )
         goto out_put;
 
     /* Decrement guest domain's ref count of the page */