fix lsvmbus failure in ready environment

create a virtual tool VmGeneration in Azure. The lsvmbus depends on it.
These tools are shared between Azure and Hyper-V, will be moved to some
shared folder, when Hyper-V implements.

lisa/sut_orchestrator/azure/platform_.py

@@ -43,7 +43,7 @@
 from lisa.node import Node, RemoteNode
 from lisa.platform_ import Platform
 from lisa.secret import PATTERN_GUID, PATTERN_HEADTAIL, add_secret
-from lisa.sut_orchestrator.azure.tools import Waagent
+from lisa.sut_orchestrator.azure.tools import VmGeneration, Waagent
 from lisa.tools import Dmesg, Modinfo
 from lisa.util import (
     LisaException,
@@ -536,10 +536,7 @@ def _get_node_information(self, node: Node) -> Dict[str, str]:
         information["lis_version"] = modinfo.get_version("hv_vmbus")
 
         node.log.debug("detecting vm generation...")
-        information[KEY_VM_GENERATION] = "1"
-        cmd_result = node.execute(cmd="ls -lt /sys/firmware/efi", no_error_log=True)
-        if cmd_result.exit_code == 0:
-            information[KEY_VM_GENERATION] = "2"
+        information[KEY_VM_GENERATION] = node.tools[VmGeneration].get_generation()
         node.log.debug(f"vm generation: {information[KEY_VM_GENERATION]}")
 
         return information

lisa/sut_orchestrator/azure/tools.py

@@ -34,3 +34,24 @@ def get_version(self) -> str:
             result = self.run("-version")
         found_version = find_patterns_in_lines(result.stdout, [self.__version_pattern])
         return found_version[0][0] if found_version[0] else ""
+
+
+class VmGeneration(Tool):
+    """
+    This is a virtual tool to detect VM generation of Hyper-V technology.
+    """
+
+    @property
+    def command(self) -> str:
+        return "ls -lt /sys/firmware/efi"
+
+    def _check_exists(self) -> bool:
+        return True
+
+    def get_generation(self) -> str:
+        cmd_result = self.run()
+        if cmd_result.exit_code == 0:
+            generation = "2"
+        else:
+            generation = "1"
+        return generation

testsuites/basic/lsvmbus.py

@@ -4,6 +4,7 @@
 
 from lisa import Environment, Node, TestCaseMetadata, TestSuite, TestSuiteMetadata
 from lisa.operating_system import Windows
+from lisa.sut_orchestrator.azure.tools import VmGeneration
 from lisa.testsuite import simple_requirement
 from lisa.tools import Lscpu, Lsvmbus
 
@@ -56,10 +57,8 @@ class LsVmBus(TestSuite):
         requirement=simple_requirement(unsupported_os=[Windows]),
     )
     def lsvmbus_channel_counting(self, environment: Environment, node: Node) -> None:
-        # get vm generation info
-        environment_information = environment.get_information()
         # get expected vm bus names
-        vmbus_class = VmbusNames(environment_information["vm_generation"] == "1")
+        vmbus_class = VmbusNames("1" == node.tools[VmGeneration].get_generation())
 
         lsvmbus_tool = node.tools[Lsvmbus]
         vmbus_list = lsvmbus_tool.get_vmbuses()