virtinst: fix caching of domain capabilities

The domain capabilities XML always contains the canonical machine name.
When the selected machine type for a guest is an alias, the check
comparing it to the domain capabilities machine will always fail. This
prevents the domain capabilities result from being cached.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

2 files changed, 25 insertions, 1 deletions

diff --git a/virtinst/capabilities.py b/virtinst/capabilities.py
index f1a0acfd..aa8fbfda 100644
--- a/virtinst/capabilities.py
+++ b/virtinst/capabilities.py
@@ -129,6 +129,19 @@ class _CapsGuest(XMLBuilder):
                 ret.append(m.canonical)
         return ret
 
+    def is_machine_alias(self, domain, src, tgt):
+        """
+        Determine if machine @src is an alias for machine @tgt
+        """
+        mobjs = (domain and domain.machines) or self.machines
+        for m in mobjs:
+            log.debug("Check %s == %s %s == %s", m.name, src, m.canonical, tgt)
+            if m.name == src and m.canonical == tgt:
+                log.debug("ok")
+                return True
+        log.debug("not ok")
+        return False
+
     def is_kvm_available(self):
         """
         Return True if kvm guests can be installed
@@ -179,6 +192,9 @@ class _CapsInfo(object):
         self.emulator = self.domain.emulator or self.guest.emulator
         self.machines = self.guest.all_machine_names(self.domain)
 
+    def is_machine_alias(self, src, tgt):
+        return self.guest.is_machine_alias(self.domain, src, tgt)
+
 
 class Capabilities(XMLBuilder):
     def __init__(self, *args, **kwargs):
diff --git a/virtinst/guest.py b/virtinst/guest.py
index 3fb9a956..2d8edbe2 100644
--- a/virtinst/guest.py
+++ b/virtinst/guest.py
@@ -618,13 +618,21 @@ class Guest(XMLBuilder):
         return True
 
     def lookup_domcaps(self):
+        def _compare_machine(domcaps):
+            capsinfo = self.lookup_capsinfo()
+            if self.os.machine == domcaps.machine:
+                return True
+            if capsinfo.is_machine_alias(self.os.machine, domcaps.machine):
+                return True
+            return False
+
         # We need to regenerate domcaps cache if any of these values change
         def _compare(domcaps):  # pragma: no cover
             if self.type == "test":
                 # Test driver doesn't support domcaps. We kinda fake it in
                 # some cases, but it screws up the checking here for parsed XML
                 return True
-            if self.os.machine and self.os.machine != domcaps.machine:
+            if self.os.machine and not _compare_machine(domcaps):
                 return False
             if self.type and self.type != domcaps.domain:
                 return False