x86, hvm: Guest CPUID configuration.

CPUID's replies are now pre-calculated in libxc and given to the
hypervisor via a new domctl.

There are two parts to this feature:
   - We can overwrite cpuid's replies.
   - We can check that a vm is compatible with a host's processor.

Signed-off-by: Jean Guyader <jean.guyader@eu.citrix.com>
Signed-off-by: Keir Fraser <keir.fraser@citrix.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/tools/examples/xmexample.hvm b/tools/examples/xmexample.hvm
index 1a1f2487a6..689a1bc216 100644
--- a/tools/examples/xmexample.hvm
+++ b/tools/examples/xmexample.hvm
@@ -219,3 +219,28 @@ serial='pty'
 #-----------------------------------------------------------------------------
 #   Set keyboard layout, default is en-us keyboard. 
 #keymap='ja'
+
+#-----------------------------------------------------------------------------
+#   Configure guest CPUID responses:
+#cpuid=[ '1:ecx=xxxxxxxxxxxxxxxxxxxxxxxxxx1xxxxx,
+#           eax=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx' ]
+# - Set the VMX feature flag in the guest (CPUID_1:ECX:5)
+# - Default behaviour for all other bits in ECX And EAX registers.
+# 
+# Each successive character represent a lesser-significant bit:
+#  '1' -> force the corresponding bit to 1
+#  '0' -> force to 0
+#  'x' -> we don't care (default behaviour)
+#  'k' -> pass through the host bit value
+#  's' -> as 'k' but preserve across save/restore and migration
+#
+#   Configure host CPUID consistency checks, which must be satisfied for this
+#   VM to be allowed to run on this host's processor type:
+#cpuid_check=[ '1:ecx=xxxxxxxxxxxxxxxxxxxxxxxxxx1xxxxx' ]
+# - Host must have VMX feature flag set
+#
+# The format is similar to the above for 'cpuid':
+#  '1' -> the bit must be '1'
+#  '0' -> the bit must be '0'
+#  'x' -> we don't care (do not check)
+#  's' -> the bit must be the same as on the host that started this VM