File libxc-sr-5588ebcfca774477cf823949e5703b0ac48818... of Package xen

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File libxc-sr-5588ebcfca774477cf823949e5703b0ac48818cc.patch of Package xen (Revision 33042d24ba9b4d7bf9fa2ba76b40af4d)

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From: Olaf Hering <olaf@aepfle.de>
Date: Thu, 1 Jul 2021 11:56:07 +0200
Subject: libxc sr 5588ebcfca774477cf823949e5703b0ac48818cc

tools/migration: unify type checking for data pfns in the VM

Introduce a helper which decides if a given pfn in the migration
stream is backed by memory.

This highlights more clearly that type XEN_DOMCTL_PFINFO_XALLOC (a
synthetic toolstack-only type used between Xen 4.2 to 4.5 which
indicated a dirty page on the sending side for which no data will be
send in the initial iteration) does get populated in the VM.

No change in behaviour intended, except for invalid page types which now
have a safer default.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit 5588ebcfca774477cf823949e5703b0ac48818cc)
---
 tools/libs/guest/xg_sr_common.h  |   29 +++++++++++++++++++++++++++++
 tools/libs/guest/xg_sr_restore.c |    4 +---
 2 files changed, 30 insertions(+), 3 deletions(-)

--- a/tools/libs/guest/xg_sr_common.h
+++ b/tools/libs/guest/xg_sr_common.h
@@ -484,6 +484,35 @@ static inline bool is_known_page_type(ui
     }
 }
 
+/* Page type backed by RAM in the guest? */
+static inline bool page_type_to_populate(uint32_t type)
+{
+    switch ( type )
+    {
+    case XEN_DOMCTL_PFINFO_NOTAB:
+
+    case XEN_DOMCTL_PFINFO_L1TAB:
+    case XEN_DOMCTL_PFINFO_L1TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L2TAB:
+    case XEN_DOMCTL_PFINFO_L2TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L3TAB:
+    case XEN_DOMCTL_PFINFO_L3TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L4TAB:
+    case XEN_DOMCTL_PFINFO_L4TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_XALLOC:
+        return true;
+
+    case XEN_DOMCTL_PFINFO_XTAB:
+    case XEN_DOMCTL_PFINFO_BROKEN:
+    default:
+        return false;
+    }
+}
+
 #endif
 /*
  * Local variables:
--- a/tools/libs/guest/xg_sr_restore.c
+++ b/tools/libs/guest/xg_sr_restore.c
@@ -152,9 +152,7 @@ int populate_pfns(struct xc_sr_context *
 
     for ( i = 0; i < count; ++i )
     {
-        if ( (!types || (types &&
-                         (types[i] != XEN_DOMCTL_PFINFO_XTAB &&
-                          types[i] != XEN_DOMCTL_PFINFO_BROKEN))) &&
+        if ( (!types || page_type_to_populate(types[i])) &&
              !pfn_is_populated(ctx, original_pfns[i]) )
         {
             rc = pfn_set_populated(ctx, original_pfns[i]);

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File libxc-sr-5588ebcfca774477cf823949e5703b0ac48818cc.patch of Package xen (Revision 33042d24ba9b4d7bf9fa2ba76b40af4d)

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