fix(test): skip test_cpu_topology test on Ubuntu

On Aarch64 systems we do not normalize vCPUs, we let KVM configure them.
This means that the CPU cache hierarchy exposed to the guest depends
entirely on what the KVM decides it to be.

We observed that when we're running tests on Ubuntu hosts with a 6.14
kernel the cache hierarchy is different than the one we expect on AL
hosts.

Until we decide how to deal with CPU hierarchy in a controled way (or
not) skip the test on Ubuntu systems. The actual test checks that the
host kernel version is greater or equal to 6.14.

Signed-off-by: Babis Chalios <[email protected]>

Author: bchalios

tests/integration_tests/functional/test_topology.py

@@ -2,11 +2,13 @@
 # SPDX-License-Identifier: Apache-2.0
 """Tests for ensuring correctness of CPU and cache topology in the guest."""
 
+from packaging import version
 import platform
 import subprocess
 
 import pytest
 
+from framework.utils import get_kernel_version
 import framework.utils_cpuid as utils
 from framework.properties import global_props
 
@@ -198,6 +200,12 @@ def test_cpu_topology(uvm_plain_any, num_vcpus, htt):
     """
     if htt and PLATFORM == "aarch64":
         pytest.skip("SMT is configurable only on x86.")
+
+    # TODO:Remove (or adapt) this once we unify the way we expose the CPU cache hierarchy on
+    # Aarch64 systems.
+    if version.parse(get_kernel_version()) >= version.parse("6.14"):
+        pytest.skip("Starting on 6.14 KVM exposes a different CPU cache hierarchy")
+
     vm = uvm_plain_any
     vm.spawn()
     vm.basic_config(vcpu_count=num_vcpus, smt=htt)