Use guest kernel 6.1 as default for tests where only a single kernel is tested

tests/conftest.py

@@ -510,6 +510,7 @@ def guest_kernel_fxt(request, record_property):
     guest_kernel_fxt,
     params=kernel_params("vmlinux-6.1*"),
 )
+guest_kernel_default = guest_kernel_linux_6_1
 
 
 @pytest.fixture
@@ -535,15 +536,9 @@ def rootfs_rw():
 
 
 @pytest.fixture
-def uvm_plain(microvm_factory, guest_kernel_linux_5_10, rootfs, pci_enabled):
+def uvm_plain(microvm_factory, guest_kernel_default, rootfs, pci_enabled):
     """Create a vanilla VM, non-parametrized"""
-    return microvm_factory.build(guest_kernel_linux_5_10, rootfs, pci=pci_enabled)
-
-
-@pytest.fixture
-def uvm_plain_6_1(microvm_factory, guest_kernel_linux_6_1, rootfs, pci_enabled):
-    """Create a vanilla VM, non-parametrized"""
-    return microvm_factory.build(guest_kernel_linux_6_1, rootfs, pci=pci_enabled)
+    return microvm_factory.build(guest_kernel_default, rootfs, pci=pci_enabled)
 
 
 @pytest.fixture
@@ -553,9 +548,9 @@ def uvm_plain_acpi(microvm_factory, guest_kernel_acpi, rootfs, pci_enabled):
 
 
 @pytest.fixture
-def uvm_plain_rw(microvm_factory, guest_kernel_linux_5_10, rootfs_rw):
+def uvm_plain_rw(microvm_factory, guest_kernel_default, rootfs_rw):
     """Create a vanilla VM, non-parametrized"""
-    return microvm_factory.build(guest_kernel_linux_5_10, rootfs_rw)
+    return microvm_factory.build(guest_kernel_default, rootfs_rw)
 
 
 @pytest.fixture

tests/integration_tests/functional/test_api.py

@@ -984,11 +984,11 @@ def test_api_entropy(uvm_plain):
         test_microvm.api.entropy.put()
 
 
-def test_api_memory_hotplug(uvm_plain_6_1):
+def test_api_memory_hotplug(uvm_plain):
     """
     Test hotplug related API commands.
     """
-    test_microvm = uvm_plain_6_1
+    test_microvm = uvm_plain
     test_microvm.spawn()
     test_microvm.basic_config()
     test_microvm.add_net_iface()

tests/integration_tests/functional/test_snapshot_basic.py

@@ -480,11 +480,11 @@ def test_snapshot_overwrite_self(uvm_plain_any, microvm_factory):
     # restored, with a new snapshot of this vm, does not break the VM
 
 
-def test_vmgenid(uvm_plain_6_1, microvm_factory, snapshot_type):
+def test_vmgenid(uvm_plain, microvm_factory, snapshot_type):
     """
     Test VMGenID device upon snapshot resume
     """
-    base_vm = uvm_plain_6_1
+    base_vm = uvm_plain
     base_vm.spawn()
     base_vm.basic_config(track_dirty_pages=True)
     base_vm.add_net_iface()

tests/integration_tests/functional/test_snapshot_not_losing_dirty_pages.py

@@ -25,13 +25,13 @@ def mount_tmpfs_small(worker_id):
 
 
 def test_diff_snapshot_works_after_error(
-    microvm_factory, guest_kernel_linux_5_10, rootfs, mount_tmpfs_small
+    microvm_factory, guest_kernel_default, rootfs, mount_tmpfs_small
 ):
     """
     Test that if a partial snapshot errors it will work after and not lose data
     """
     uvm = microvm_factory.build(
-        guest_kernel_linux_5_10,
+        guest_kernel_default,
         rootfs,
         jailer_kwargs={"chroot_base": mount_tmpfs_small},
     )

tests/integration_tests/functional/test_uffd.py

@@ -12,10 +12,10 @@
 
 
 @pytest.fixture(scope="function", name="snapshot")
-def snapshot_fxt(microvm_factory, guest_kernel_linux_5_10, rootfs):
+def snapshot_fxt(microvm_factory, guest_kernel_default, rootfs):
     """Create a snapshot of a microVM."""
 
-    basevm = microvm_factory.build(guest_kernel_linux_5_10, rootfs)
+    basevm = microvm_factory.build(guest_kernel_default, rootfs)
     basevm.spawn()
     basevm.basic_config(vcpu_count=2, mem_size_mib=256)
     basevm.add_net_iface()

tests/integration_tests/performance/test_hotplug_memory.py

@@ -136,11 +136,11 @@ def uvm_resumed_memhp(
         "resumed-uffd-huge-pages",
     ],
 )
-def uvm_any_memhp(request, uvm_plain_6_1, rootfs, microvm_factory):
+def uvm_any_memhp(request, uvm_plain, rootfs, microvm_factory):
     """Fixture that yields a booted or resumed VM with memory hotplugging"""
     ctor, vhost_user, huge_pages, uffd_handler, snapshot_type = request.param
     yield ctor(
-        uvm_plain_6_1,
+        uvm_plain,
         rootfs,
         microvm_factory,
         vhost_user,
@@ -278,13 +278,11 @@ def test_virtio_mem_hotplug_hotunplug(uvm_any_memhp):
     ],
     ids=["all_different", "slot_sized_block", "single_slot", "single_block"],
 )
-def test_virtio_mem_configs(uvm_plain_6_1, memhp_config):
+def test_virtio_mem_configs(uvm_plain, memhp_config):
     """
     Check that the virtio mem device is working as expected for different configs
     """
-    uvm = uvm_booted_memhp(
-        uvm_plain_6_1, None, None, False, memhp_config, None, None, None
-    )
+    uvm = uvm_booted_memhp(uvm_plain, None, None, False, memhp_config, None, None, None)
     if not uvm.pci_enabled:
         pytest.skip(
             "Skip tests on MMIO transport to save time as we don't expect any difference."
@@ -309,16 +307,16 @@ def test_virtio_mem_configs(uvm_plain_6_1, memhp_config):
     validate_metrics(uvm)
 
 
-def test_snapshot_restore_persistence(uvm_plain_6_1, microvm_factory, snapshot_type):
+def test_snapshot_restore_persistence(uvm_plain, microvm_factory, snapshot_type):
     """
     Check that hptplugged memory is persisted across snapshot/restore.
     """
-    if not uvm_plain_6_1.pci_enabled:
+    if not uvm_plain.pci_enabled:
         pytest.skip(
             "Skip tests on MMIO transport to save time as we don't expect any difference."
         )
     uvm = uvm_booted_memhp(
-        uvm_plain_6_1,
+        uvm_plain,
         None,
         microvm_factory,
         False,
@@ -349,17 +347,17 @@ def test_snapshot_restore_persistence(uvm_plain_6_1, microvm_factory, snapshot_t
     validate_metrics(restored_vm)
 
 
-def test_snapshot_restore_incremental(uvm_plain_6_1, microvm_factory):
+def test_snapshot_restore_incremental(uvm_plain, microvm_factory):
     """
     Check that hptplugged memory is persisted across snapshot/restore.
     """
-    if not uvm_plain_6_1.pci_enabled:
+    if not uvm_plain.pci_enabled:
         pytest.skip(
             "Skip tests on MMIO transport to save time as we don't expect any difference."
         )
 
     uvm = uvm_booted_memhp(
-        uvm_plain_6_1, None, microvm_factory, False, DEFAULT_CONFIG, None, None, None
+        uvm_plain, None, microvm_factory, False, DEFAULT_CONFIG, None, None, None
     )
 
     snapshot = uvm.snapshot_full()
@@ -457,10 +455,8 @@ def test_memory_hotplug_latency(
             "slot_size_mib": 128,
             "block_size_mib": 2,
         }
-        uvm_plain_6_1 = microvm_factory.build(guest_kernel_linux_6_1, rootfs, pci=True)
-        uvm = uvm_booted_memhp(
-            uvm_plain_6_1, None, None, False, config, None, None, None
-        )
+        uvm_plain = microvm_factory.build(guest_kernel_linux_6_1, rootfs, pci=True)
+        uvm = uvm_booted_memhp(uvm_plain, None, None, False, config, None, None, None)
 
         if i == 0:
             metrics.set_dimensions(