Change in vdsm[master]: caps: report nested virtualization capabilities - vdsm-patches - Fedora mailing-lists

25 Oct 2016

Martin Polednik has uploaded a new change for review.
Change subject: caps: report nested virtualization capabilities
......................................................................
caps: report nested virtualization capabilities
Nested virtualization capability can be easily queried without sysfs
and is necessary and sufficient to determine nested VT availability.
Moving this code to lib/osinfo also allows us to simplify nestedvt
hook - done as a part of this patch.
Change-Id: I1715413ae815c67ecc67bf7789487dbc11278919
Signed-off-by: Martin Polednik mpolednik@redhat.com
---
M lib/api/vdsm-api.yml
M lib/vdsm/osinfo.py
M vdsm/caps.py
M vdsm_hooks/nestedvt/before_vm_start.py
4 files changed, 34 insertions(+), 12 deletions(-)
git pull ssh://gerrit.ovirt.org:29418/vdsm refs/changes/17/65717/1

diff --git a/lib/api/vdsm-api.yml b/lib/api/vdsm-api.yml
index e44e06a..88635e1 100644
--- a/lib/api/vdsm-api.yml
+++ b/lib/api/vdsm-api.yml
@@ -6496,6 +6496,13 @@
             name: realtimeKernel
             type: string
             added: '4.1'
+
+        -   defaultvalue: no-default
+            description: Indication whether the system is capable of nested
+                virtualization (considers platform & module options).
+            name: nestedVirtualization
+            type: string
+            added: '4.1'
         type: object
VmShortStatus: &VmShortStatus
diff --git a/lib/vdsm/osinfo.py b/lib/vdsm/osinfo.py
index bf2cd5f..d35eaca 100644
--- a/lib/vdsm/osinfo.py
+++ b/lib/vdsm/osinfo.py
@@ -27,6 +27,7 @@
from collections import namedtuple
+from vdsm import cpuarch
 from vdsm import utils
# For debian systems we can use python-apt if available
@@ -51,6 +52,8 @@
KernelFlags = namedtuple('KernelFlags', 'version, realtime')
+NestedVirtualization = namedtuple('NestedVirtualization',
+                                  'enabled, kvm_module')
class OSName:
@@ -260,3 +263,20 @@
     realtime = 'RT' in ret[3]
return KernelFlags(dict(version=ver, release=rel), realtime)
+
+
+@utils.memoized
+def nested_virtualization():
+    if cpuarch.is_ppc(cpuarch.real()):
+        return NestedVirtualization(False, None)
+
+    for kvm_module in ("kvm_intel", "kvm_amd"):
+        kvm_module_path = "/sys/module/%s/parameters/nested" % kvm_module
+        try:
+            with open(kvm_module_path) as f:
+                if f.readline().strip() in ("Y", "1"):
+                    return NestedVirtualization(True, kvm_module)
+        except IOError:
+            logging.debug('Could not determine status of nested '
+                          'virtualization', exc_info=True)
+            return NestedVirtualization(False, None)
diff --git a/vdsm/caps.py b/vdsm/caps.py
index 57ea7e9..b12e6df 100644
--- a/vdsm/caps.py
+++ b/vdsm/caps.py
@@ -170,6 +170,8 @@
     caps['packages2'] = osinfo.package_versions()
     caps['realtimeKernel'] = str(
         osinfo.runtime_kernel_flags().realtime).lower()
+    caps['nestedVirtualization'] = str(
+        osinfo.nested_virtualization().enabled).lower()
     caps['emulatedMachines'] = machinetype.emulated_machines(
         cpuarch.effective())
     caps['ISCSIInitiatorName'] = _getIscsiIniName()
diff --git a/vdsm_hooks/nestedvt/before_vm_start.py b/vdsm_hooks/nestedvt/before_vm_start.py
index 5ea71f4..f245e3f 100755
--- a/vdsm_hooks/nestedvt/before_vm_start.py
+++ b/vdsm_hooks/nestedvt/before_vm_start.py
@@ -21,26 +21,19 @@
import hooking
+from vdsm import osinfo
+
 cpu_nested_features = {
     "kvm_intel": "vmx",
     "kvm_amd": "svm",
 }
-for kvm_mod in ("kvm_intel", "kvm_amd"):
-    kvm_mod_path = "/sys/module/%s/parameters/nested" % kvm_mod
-    try:
-        with open(kvm_mod_path) as f:
-            if f.readline().strip() in ("Y", "1"):
-                break
-    except IOError:
-        pass
-else:
-    kvm_mod = None
+nestedvt = osinfo.nested_virtualization()
-if kvm_mod:
+if nestedvt.status:
     domxml = hooking.read_domxml()
     feature_vmx = domxml.createElement("feature")
-    feature_vmx.setAttribute("name", cpu_nested_features[kvm_mod])
+    feature_vmx.setAttribute("name", cpu_nested_features[nestedvt.kvm_module])
     feature_vmx.setAttribute("policy", "require")
     domxml.getElementsByTagName("cpu")[0].appendChild(feature_vmx)
     hooking.write_domxml(domxml)
-- 
To view, visit https://gerrit.ovirt.org/65717
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Gerrit-MessageType: newchange
Gerrit-Change-Id: I1715413ae815c67ecc67bf7789487dbc11278919
Gerrit-PatchSet: 1
Gerrit-Project: vdsm
Gerrit-Branch: master
Gerrit-Owner: Martin Polednik mpolednik@redhat.com

    