cloudinit: move dmi functions out of util (#622)

This just separates the reading of dmi values into its own file.

Some things of note:
 * left import of util in dmi.py only for 'is_container'
   It'd be good if is_container was not in util.
 * just the use of 'util.is_x86' to dmi.py
 * open() is used directly rather than load_file.

28 files changed, 348 insertions, 312 deletions

diff --git a/cloudinit/dmi.py b/cloudinit/dmi.py
new file mode 100644
index 00000000..96e0e423
--- /dev/null
+++ b/cloudinit/dmi.py
@@ -0,0 +1,131 @@
+# This file is part of cloud-init. See LICENSE file for license information.
+from cloudinit import log as logging
+from cloudinit import subp
+from cloudinit.util import is_container
+
+import os
+
+LOG = logging.getLogger(__name__)
+
+# Path for DMI Data
+DMI_SYS_PATH = "/sys/class/dmi/id"
+
+# dmidecode and /sys/class/dmi/id/* use different names for the same value,
+# this allows us to refer to them by one canonical name
+DMIDECODE_TO_DMI_SYS_MAPPING = {
+    'baseboard-asset-tag': 'board_asset_tag',
+    'baseboard-manufacturer': 'board_vendor',
+    'baseboard-product-name': 'board_name',
+    'baseboard-serial-number': 'board_serial',
+    'baseboard-version': 'board_version',
+    'bios-release-date': 'bios_date',
+    'bios-vendor': 'bios_vendor',
+    'bios-version': 'bios_version',
+    'chassis-asset-tag': 'chassis_asset_tag',
+    'chassis-manufacturer': 'chassis_vendor',
+    'chassis-serial-number': 'chassis_serial',
+    'chassis-version': 'chassis_version',
+    'system-manufacturer': 'sys_vendor',
+    'system-product-name': 'product_name',
+    'system-serial-number': 'product_serial',
+    'system-uuid': 'product_uuid',
+    'system-version': 'product_version',
+}
+
+
+def _read_dmi_syspath(key):
+    """
+    Reads dmi data with from /sys/class/dmi/id
+    """
+    if key not in DMIDECODE_TO_DMI_SYS_MAPPING:
+        return None
+    mapped_key = DMIDECODE_TO_DMI_SYS_MAPPING[key]
+    dmi_key_path = "{0}/{1}".format(DMI_SYS_PATH, mapped_key)
+
+    LOG.debug("querying dmi data %s", dmi_key_path)
+    if not os.path.exists(dmi_key_path):
+        LOG.debug("did not find %s", dmi_key_path)
+        return None
+
+    try:
+        with open(dmi_key_path, "rb") as fp:
+            key_data = fp.read()
+    except PermissionError:
+        LOG.debug("Could not read %s", dmi_key_path)
+        return None
+
+    # uninitialized dmi values show as all \xff and /sys appends a '\n'.
+    # in that event, return empty string.
+    if key_data == b'\xff' * (len(key_data) - 1) + b'\n':
+        key_data = b""
+
+    try:
+        return key_data.decode('utf8').strip()
+    except UnicodeDecodeError as e:
+        LOG.error("utf-8 decode of content (%s) in %s failed: %s",
+                  dmi_key_path, key_data, e)
+
+    return None
+
+
+def _call_dmidecode(key, dmidecode_path):
+    """
+    Calls out to dmidecode to get the data out. This is mostly for supporting
+    OS's without /sys/class/dmi/id support.
+    """
+    try:
+        cmd = [dmidecode_path, "--string", key]
+        (result, _err) = subp.subp(cmd)
+        result = result.strip()
+        LOG.debug("dmidecode returned '%s' for '%s'", result, key)
+        if result.replace(".", "") == "":
+            return ""
+        return result
+    except (IOError, OSError) as e:
+        LOG.debug('failed dmidecode cmd: %s\n%s', cmd, e)
+        return None
+
+
+def read_dmi_data(key):
+    """
+    Wrapper for reading DMI data.
+
+    If running in a container return None.  This is because DMI data is
+    assumed to be not useful in a container as it does not represent the
+    container but rather the host.
+
+    This will do the following (returning the first that produces a
+    result):
+        1) Use a mapping to translate `key` from dmidecode naming to
+           sysfs naming and look in /sys/class/dmi/... for a value.
+        2) Use `key` as a sysfs key directly and look in /sys/class/dmi/...
+        3) Fall-back to passing `key` to `dmidecode --string`.
+
+    If all of the above fail to find a value, None will be returned.
+    """
+
+    if is_container():
+        return None
+
+    syspath_value = _read_dmi_syspath(key)
+    if syspath_value is not None:
+        return syspath_value
+
+    def is_x86(arch):
+        return (arch == 'x86_64' or (arch[0] == 'i' and arch[2:] == '86'))
+
+    # running dmidecode can be problematic on some arches (LP: #1243287)
+    uname_arch = os.uname()[4]
+    if not (is_x86(uname_arch) or uname_arch in ('aarch64', 'amd64')):
+        LOG.debug("dmidata is not supported on %s", uname_arch)
+        return None
+
+    dmidecode_path = subp.which('dmidecode')
+    if dmidecode_path:
+        return _call_dmidecode(key, dmidecode_path)
+
+    LOG.warning("did not find either path %s or dmidecode command",
+                DMI_SYS_PATH)
+    return None
+
+# vi: ts=4 expandtab
diff --git a/cloudinit/sources/DataSourceAliYun.py b/cloudinit/sources/DataSourceAliYun.py
index 45cc9f00..09052873 100644
--- a/cloudinit/sources/DataSourceAliYun.py
+++ b/cloudinit/sources/DataSourceAliYun.py
@@ -1,8 +1,8 @@
 # This file is part of cloud-init. See LICENSE file for license information.
 
+from cloudinit import dmi
 from cloudinit import sources
 from cloudinit.sources import DataSourceEc2 as EC2
-from cloudinit import util
 
 ALIYUN_PRODUCT = "Alibaba Cloud ECS"
 
@@ -30,7 +30,7 @@ class DataSourceAliYun(EC2.DataSourceEc2):
 
 
 def _is_aliyun():
-    return util.read_dmi_data('system-product-name') == ALIYUN_PRODUCT
+    return dmi.read_dmi_data('system-product-name') == ALIYUN_PRODUCT
 
 
 def parse_public_keys(public_keys):
diff --git a/cloudinit/sources/DataSourceAltCloud.py b/cloudinit/sources/DataSourceAltCloud.py
index ac3ecc3d..cd93412a 100644
--- a/cloudinit/sources/DataSourceAltCloud.py
+++ b/cloudinit/sources/DataSourceAltCloud.py
@@ -16,6 +16,7 @@ import errno
 import os
 import os.path
 
+from cloudinit import dmi
 from cloudinit import log as logging
 from cloudinit import sources
 from cloudinit import subp
@@ -109,7 +110,7 @@ class DataSourceAltCloud(sources.DataSource):
                             CLOUD_INFO_FILE)
                 return 'UNKNOWN'
             return cloud_type
-        system_name = util.read_dmi_data("system-product-name")
+        system_name = dmi.read_dmi_data("system-product-name")
         if not system_name:
             return 'UNKNOWN'
 
diff --git a/cloudinit/sources/DataSourceAzure.py b/cloudinit/sources/DataSourceAzure.py
index 70e32f46..fa3e0a2b 100755
--- a/cloudinit/sources/DataSourceAzure.py
+++ b/cloudinit/sources/DataSourceAzure.py
@@ -15,6 +15,7 @@ from time import time
 from xml.dom import minidom
 import xml.etree.ElementTree as ET
 
+from cloudinit import dmi
 from cloudinit import log as logging
 from cloudinit import net
 from cloudinit.event import EventType
@@ -630,7 +631,7 @@ class DataSourceAzure(sources.DataSource):
     def _iid(self, previous=None):
         prev_iid_path = os.path.join(
             self.paths.get_cpath('data'), 'instance-id')
-        iid = util.read_dmi_data('system-uuid')
+        iid = dmi.read_dmi_data('system-uuid')
         if os.path.exists(prev_iid_path):
             previous = util.load_file(prev_iid_path).strip()
             if is_byte_swapped(previous, iid):
@@ -1630,7 +1631,7 @@ def _is_platform_viable(seed_dir):
         description="found azure asset tag",
         parent=azure_ds_reporter
     ) as evt:
-        asset_tag = util.read_dmi_data('chassis-asset-tag')
+        asset_tag = dmi.read_dmi_data('chassis-asset-tag')
         if asset_tag == AZURE_CHASSIS_ASSET_TAG:
             return True
         msg = "Non-Azure DMI asset tag '%s' discovered." % asset_tag
diff --git a/cloudinit/sources/DataSourceCloudSigma.py b/cloudinit/sources/DataSourceCloudSigma.py
index df88f677..f63baf74 100644
--- a/cloudinit/sources/DataSourceCloudSigma.py
+++ b/cloudinit/sources/DataSourceCloudSigma.py
@@ -9,9 +9,9 @@ import re
 
 from cloudinit.cs_utils import Cepko, SERIAL_PORT
 
+from cloudinit import dmi
 from cloudinit import log as logging
 from cloudinit import sources
-from cloudinit import util
 
 LOG = logging.getLogger(__name__)
 
@@ -38,7 +38,7 @@ class DataSourceCloudSigma(sources.DataSource):
         """
 
         LOG.debug("determining hypervisor product name via dmi data")
-        sys_product_name = util.read_dmi_data("system-product-name")
+        sys_product_name = dmi.read_dmi_data("system-product-name")
         if not sys_product_name:
             LOG.debug("system-product-name not available in dmi data")
             return False
diff --git a/cloudinit/sources/DataSourceEc2.py b/cloudinit/sources/DataSourceEc2.py
index 1d09c12a..1930a509 100644
--- a/cloudinit/sources/DataSourceEc2.py
+++ b/cloudinit/sources/DataSourceEc2.py
@@ -11,6 +11,7 @@
 import os
 import time
 
+from cloudinit import dmi
 from cloudinit import ec2_utils as ec2
 from cloudinit import log as logging
 from cloudinit import net
@@ -699,26 +700,26 @@ def _collect_platform_data():
         uuid = util.load_file("/sys/hypervisor/uuid").strip()
         data['uuid_source'] = 'hypervisor'
     except Exception:
-        uuid = util.read_dmi_data('system-uuid')
+        uuid = dmi.read_dmi_data('system-uuid')
         data['uuid_source'] = 'dmi'
 
     if uuid is None:
         uuid = ''
     data['uuid'] = uuid.lower()
 
-    serial = util.read_dmi_data('system-serial-number')
+    serial = dmi.read_dmi_data('system-serial-number')
     if serial is None:
         serial = ''
 
     data['serial'] = serial.lower()
 
-    asset_tag = util.read_dmi_data('chassis-asset-tag')
+    asset_tag = dmi.read_dmi_data('chassis-asset-tag')
     if asset_tag is None:
         asset_tag = ''
 
     data['asset_tag'] = asset_tag.lower()
 
-    vendor = util.read_dmi_data('system-manufacturer')
+    vendor = dmi.read_dmi_data('system-manufacturer')
     data['vendor'] = (vendor if vendor else '').lower()
 
     return data
diff --git a/cloudinit/sources/DataSourceExoscale.py b/cloudinit/sources/DataSourceExoscale.py
index d59aefd1..adee6d79 100644
--- a/cloudinit/sources/DataSourceExoscale.py
+++ b/cloudinit/sources/DataSourceExoscale.py
@@ -3,6 +3,7 @@
 #
 # This file is part of cloud-init. See LICENSE file for license information.
 
+from cloudinit import dmi
 from cloudinit import ec2_utils as ec2
 from cloudinit import log as logging
 from cloudinit import sources
@@ -135,7 +136,7 @@ class DataSourceExoscale(sources.DataSource):
         return self.extra_config
 
     def _is_platform_viable(self):
-        return util.read_dmi_data('system-product-name').startswith(
+        return dmi.read_dmi_data('system-product-name').startswith(
             EXOSCALE_DMI_NAME)
 
 
diff --git a/cloudinit/sources/DataSourceGCE.py b/cloudinit/sources/DataSourceGCE.py
index 0ec5f6ec..746caddb 100644
--- a/cloudinit/sources/DataSourceGCE.py
+++ b/cloudinit/sources/DataSourceGCE.py
@@ -7,6 +7,7 @@ import json
 
 from base64 import b64decode
 
+from cloudinit import dmi
 from cloudinit.distros import ug_util
 from cloudinit import log as logging
 from cloudinit import sources
@@ -248,12 +249,12 @@ def read_md(address=None, platform_check=True):
 
 
 def platform_reports_gce():
-    pname = util.read_dmi_data('system-product-name') or "N/A"
+    pname = dmi.read_dmi_data('system-product-name') or "N/A"
     if pname == "Google Compute Engine":
         return True
 
     # system-product-name is not always guaranteed (LP: #1674861)
-    serial = util.read_dmi_data('system-serial-number') or "N/A"
+    serial = dmi.read_dmi_data('system-serial-number') or "N/A"
     if serial.startswith("GoogleCloud-"):
         return True
 
diff --git a/cloudinit/sources/DataSourceHetzner.py b/cloudinit/sources/DataSourceHetzner.py
index 8e4d4b69..c7c88dd7 100644
--- a/cloudinit/sources/DataSourceHetzner.py
+++ b/cloudinit/sources/DataSourceHetzner.py
@@ -6,6 +6,7 @@
 """Hetzner Cloud API Documentation
    https://docs.hetzner.cloud/"""
 
+from cloudinit import dmi
 from cloudinit import log as logging
 from cloudinit import net as cloudnet
 from cloudinit import sources
@@ -113,11 +114,11 @@ class DataSourceHetzner(sources.DataSource):
 
 
 def get_hcloud_data():
-    vendor_name = util.read_dmi_data('system-manufacturer')
+    vendor_name = dmi.read_dmi_data('system-manufacturer')
     if vendor_name != "Hetzner":
         return (False, None)
 
-    serial = util.read_dmi_data("system-serial-number")
+    serial = dmi.read_dmi_data("system-serial-number")
     if serial:
         LOG.debug("Running on Hetzner Cloud: serial=%s", serial)
     else:
diff --git a/cloudinit/sources/DataSourceNoCloud.py b/cloudinit/sources/DataSourceNoCloud.py
index d4a175e8..a126aad3 100644
--- a/cloudinit/sources/DataSourceNoCloud.py
+++ b/cloudinit/sources/DataSourceNoCloud.py
@@ -11,6 +11,7 @@
 import errno
 import os
 
+from cloudinit import dmi
 from cloudinit import log as logging
 from cloudinit.net import eni
 from cloudinit import sources
@@ -61,7 +62,7 @@ class DataSourceNoCloud(sources.DataSource):
             # Parse the system serial label from dmi. If not empty, try parsing
             # like the commandline
             md = {}
-            serial = util.read_dmi_data('system-serial-number')
+            serial = dmi.read_dmi_data('system-serial-number')
             if serial and load_cmdline_data(md, serial):
                 found.append("dmi")
                 mydata = _merge_new_seed(mydata, {'meta-data': md})
diff --git a/cloudinit/sources/DataSourceOVF.py b/cloudinit/sources/DataSourceOVF.py
index a5ccb8f6..741c140a 100644
--- a/cloudinit/sources/DataSourceOVF.py
+++ b/cloudinit/sources/DataSourceOVF.py
@@ -14,6 +14,7 @@ import re
 import time
 from xml.dom import minidom
 
+from cloudinit import dmi
 from cloudinit import log as logging
 from cloudinit import sources
 from cloudinit import subp
@@ -83,7 +84,7 @@ class DataSourceOVF(sources.DataSource):
 
         (seedfile, contents) = get_ovf_env(self.paths.seed_dir)
 
-        system_type = util.read_dmi_data("system-product-name")
+        system_type = dmi.read_dmi_data("system-product-name")
         if system_type is None:
             LOG.debug("No system-product-name found")
 
@@ -322,7 +323,7 @@ class DataSourceOVF(sources.DataSource):
         return True
 
     def _get_subplatform(self):
-        system_type = util.read_dmi_data("system-product-name").lower()
+        system_type = dmi.read_dmi_data("system-product-name").lower()
         if system_type == 'vmware':
             return 'vmware (%s)' % self.seed
         return 'ovf (%s)' % self.seed
diff --git a/cloudinit/sources/DataSourceOpenStack.py b/cloudinit/sources/DataSourceOpenStack.py
index 0ede0a0e..b3406c67 100644
--- a/cloudinit/sources/DataSourceOpenStack.py
+++ b/cloudinit/sources/DataSourceOpenStack.py
@@ -6,6 +6,7 @@
 
 import time
 
+from cloudinit import dmi
 from cloudinit import log as logging
 from cloudinit.net.dhcp import EphemeralDHCPv4, NoDHCPLeaseError
 from cloudinit import sources
@@ -225,10 +226,10 @@ def detect_openstack(accept_oracle=False):
     """Return True when a potential OpenStack platform is detected."""
     if not util.is_x86():
         return True  # Non-Intel cpus don't properly report dmi product names
-    product_name = util.read_dmi_data('system-product-name')
+    product_name = dmi.read_dmi_data('system-product-name')
     if product_name in VALID_DMI_PRODUCT_NAMES:
         return True
-    elif util.read_dmi_data('chassis-asset-tag') in VALID_DMI_ASSET_TAGS:
+    elif dmi.read_dmi_data('chassis-asset-tag') in VALID_DMI_ASSET_TAGS:
         return True
     elif accept_oracle and oracle._is_platform_viable():
         return True
diff --git a/cloudinit/sources/DataSourceOracle.py b/cloudinit/sources/DataSourceOracle.py
index 20d6487d..bf81b10b 100644
--- a/cloudinit/sources/DataSourceOracle.py
+++ b/cloudinit/sources/DataSourceOracle.py
@@ -17,6 +17,7 @@ import base64
 from collections import namedtuple
 from contextlib import suppress as noop
 
+from cloudinit import dmi
 from cloudinit import log as logging
 from cloudinit import net, sources, util
 from cloudinit.net import (
@@ -273,12 +274,12 @@ class DataSourceOracle(sources.DataSource):
 
 
 def _read_system_uuid():
-    sys_uuid = util.read_dmi_data('system-uuid')
+    sys_uuid = dmi.read_dmi_data('system-uuid')
     return None if sys_uuid is None else sys_uuid.lower()
 
 
 def _is_platform_viable():
-    asset_tag = util.read_dmi_data('chassis-asset-tag')
+    asset_tag = dmi.read_dmi_data('chassis-asset-tag')
     return asset_tag == CHASSIS_ASSET_TAG
 
 
diff --git a/cloudinit/sources/DataSourceScaleway.py b/cloudinit/sources/DataSourceScaleway.py
index 83c2bf65..41be7665 100644
--- a/cloudinit/sources/DataSourceScaleway.py
+++ b/cloudinit/sources/DataSourceScaleway.py
@@ -25,6 +25,7 @@ import requests
 from requests.packages.urllib3.connection import HTTPConnection
 from requests.packages.urllib3.poolmanager import PoolManager
 
+from cloudinit import dmi
 from cloudinit import log as logging
 from cloudinit import sources
 from cloudinit import url_helper
@@ -56,7 +57,7 @@ def on_scaleway():
     * the initrd created the file /var/run/scaleway.
     * "scaleway" is in the kernel cmdline.
     """
-    vendor_name = util.read_dmi_data('system-manufacturer')
+    vendor_name = dmi.read_dmi_data('system-manufacturer')
     if vendor_name == 'Scaleway':
         return True
 
diff --git a/cloudinit/sources/DataSourceSmartOS.py b/cloudinit/sources/DataSourceSmartOS.py
index f1f903bc..fd292baa 100644
--- a/cloudinit/sources/DataSourceSmartOS.py
+++ b/cloudinit/sources/DataSourceSmartOS.py
@@ -30,6 +30,7 @@ import random
 import re
 import socket
 
+from cloudinit import dmi
 from cloudinit import log as logging
 from cloudinit import serial
 from cloudinit import sources
@@ -767,7 +768,7 @@ def get_smartos_environ(uname_version=None, product_name=None):
         return SMARTOS_ENV_LX_BRAND
 
     if product_name is None:
-        system_type = util.read_dmi_data("system-product-name")
+        system_type = dmi.read_dmi_data("system-product-name")
     else:
         system_type = product_name
 
diff --git a/cloudinit/sources/__init__.py b/cloudinit/sources/__init__.py
index c4d60fff..9dccc687 100644
--- a/cloudinit/sources/__init__.py
+++ b/cloudinit/sources/__init__.py
@@ -14,6 +14,7 @@ import json
 import os
 from collections import namedtuple
 
+from cloudinit import dmi
 from cloudinit import importer
 from cloudinit import log as logging
 from cloudinit import net
@@ -809,7 +810,7 @@ def instance_id_matches_system_uuid(instance_id, field='system-uuid'):
     if not instance_id:
         return False
 
-    dmi_value = util.read_dmi_data(field)
+    dmi_value = dmi.read_dmi_data(field)
     if not dmi_value:
         return False
     return instance_id.lower() == dmi_value.lower()
diff --git a/cloudinit/sources/helpers/digitalocean.py b/cloudinit/sources/helpers/digitalocean.py
index b545c4d6..f9be4ecb 100644
--- a/cloudinit/sources/helpers/digitalocean.py
+++ b/cloudinit/sources/helpers/digitalocean.py
@@ -5,6 +5,7 @@
 import json
 import random
 
+from cloudinit import dmi
 from cloudinit import log as logging
 from cloudinit import net as cloudnet
 from cloudinit import url_helper
@@ -195,11 +196,11 @@ def read_sysinfo():
     # SMBIOS information
 
     # Detect if we are on DigitalOcean and return the Droplet's ID
-    vendor_name = util.read_dmi_data("system-manufacturer")
+    vendor_name = dmi.read_dmi_data("system-manufacturer")
     if vendor_name != "DigitalOcean":
         return (False, None)
 
-    droplet_id = util.read_dmi_data("system-serial-number")
+    droplet_id = dmi.read_dmi_data("system-serial-number")
     if droplet_id:
         LOG.debug("system identified via SMBIOS as DigitalOcean Droplet: %s",
                   droplet_id)
diff --git a/cloudinit/sources/tests/test_oracle.py b/cloudinit/sources/tests/test_oracle.py
index 7bd23813..a7bbdfd9 100644
--- a/cloudinit/sources/tests/test_oracle.py
+++ b/cloudinit/sources/tests/test_oracle.py
@@ -153,20 +153,20 @@ class TestDataSourceOracle:
 
 
 class TestIsPlatformViable(test_helpers.CiTestCase):
-    @mock.patch(DS_PATH + ".util.read_dmi_data",
+    @mock.patch(DS_PATH + ".dmi.read_dmi_data",
                 return_value=oracle.CHASSIS_ASSET_TAG)
     def test_expected_viable(self, m_read_dmi_data):
         """System with known chassis tag is viable."""
         self.assertTrue(oracle._is_platform_viable())
         m_read_dmi_data.assert_has_calls([mock.call('chassis-asset-tag')])
 
-    @mock.patch(DS_PATH + ".util.read_dmi_data", return_value=None)
+    @mock.patch(DS_PATH + ".dmi.read_dmi_data", return_value=None)
     def test_expected_not_viable_dmi_data_none(self, m_read_dmi_data):
         """System without known chassis tag is not viable."""
         self.assertFalse(oracle._is_platform_viable())
         m_read_dmi_data.assert_has_calls([mock.call('chassis-asset-tag')])
 
-    @mock.patch(DS_PATH + ".util.read_dmi_data", return_value="LetsGoCubs")
+    @mock.patch(DS_PATH + ".dmi.read_dmi_data", return_value="LetsGoCubs")
     def test_expected_not_viable_other(self, m_read_dmi_data):
         """System with unnown chassis tag is not viable."""
         self.assertFalse(oracle._is_platform_viable())
diff --git a/cloudinit/tests/test_dmi.py b/cloudinit/tests/test_dmi.py
new file mode 100644
index 00000000..4a8af257
--- /dev/null
+++ b/cloudinit/tests/test_dmi.py
@@ -0,0 +1,131 @@
+from cloudinit.tests import helpers
+from cloudinit import dmi
+from cloudinit import util
+from cloudinit import subp
+
+import os
+import tempfile
+import shutil
+from unittest import mock
+
+
+class TestReadDMIData(helpers.FilesystemMockingTestCase):
+
+    def setUp(self):
+        super(TestReadDMIData, self).setUp()
+        self.new_root = tempfile.mkdtemp()
+        self.addCleanup(shutil.rmtree, self.new_root)
+        self.reRoot(self.new_root)
+        p = mock.patch("cloudinit.dmi.is_container", return_value=False)
+        self.addCleanup(p.stop)
+        self._m_is_container = p.start()
+
+    def _create_sysfs_parent_directory(self):
+        util.ensure_dir(os.path.join('sys', 'class', 'dmi', 'id'))
+
+    def _create_sysfs_file(self, key, content):
+        """Mocks the sys path found on Linux systems."""
+        self._create_sysfs_parent_directory()
+        dmi_key = "/sys/class/dmi/id/{0}".format(key)
+        util.write_file(dmi_key, content)
+
+    def _configure_dmidecode_return(self, key, content, error=None):
+        """
+        In order to test a missing sys path and call outs to dmidecode, this
+        function fakes the results of dmidecode to test the results.
+        """
+        def _dmidecode_subp(cmd):
+            if cmd[-1] != key:
+                raise subp.ProcessExecutionError()
+            return (content, error)
+
+        self.patched_funcs.enter_context(
+            mock.patch("cloudinit.dmi.subp.which", side_effect=lambda _: True))
+        self.patched_funcs.enter_context(
+            mock.patch("cloudinit.dmi.subp.subp", side_effect=_dmidecode_subp))
+
+    def patch_mapping(self, new_mapping):
+        self.patched_funcs.enter_context(
+            mock.patch('cloudinit.dmi.DMIDECODE_TO_DMI_SYS_MAPPING',
+                       new_mapping))
+
+    def test_sysfs_used_with_key_in_mapping_and_file_on_disk(self):
+        self.patch_mapping({'mapped-key': 'mapped-value'})
+        expected_dmi_value = 'sys-used-correctly'
+        self._create_sysfs_file('mapped-value', expected_dmi_value)
+        self._configure_dmidecode_return('mapped-key', 'wrong-wrong-wrong')
+        self.assertEqual(expected_dmi_value, dmi.read_dmi_data('mapped-key'))
+
+    def test_dmidecode_used_if_no_sysfs_file_on_disk(self):
+        self.patch_mapping({})
+        self._create_sysfs_parent_directory()
+        expected_dmi_value = 'dmidecode-used'
+        self._configure_dmidecode_return('use-dmidecode', expected_dmi_value)
+        with mock.patch("cloudinit.util.os.uname") as m_uname:
+            m_uname.return_value = ('x-sysname', 'x-nodename',
+                                    'x-release', 'x-version', 'x86_64')
+            self.assertEqual(expected_dmi_value,
+                             dmi.read_dmi_data('use-dmidecode'))
+
+    def test_dmidecode_not_used_on_arm(self):
+        self.patch_mapping({})
+        print("current =%s", subp)
+        self._create_sysfs_parent_directory()
+        dmi_val = 'from-dmidecode'
+        dmi_name = 'use-dmidecode'
+        self._configure_dmidecode_return(dmi_name, dmi_val)
+        print("now =%s", subp)
+
+        expected = {'armel': None, 'aarch64': dmi_val, 'x86_64': dmi_val}
+        found = {}
+        # we do not run the 'dmi-decode' binary on some arches
+        # verify that anything requested that is not in the sysfs dir
+        # will return None on those arches.
+        with mock.patch("cloudinit.util.os.uname") as m_uname:
+            for arch in expected:
+                m_uname.return_value = ('x-sysname', 'x-nodename',
+                                        'x-release', 'x-version', arch)
+                print("now2 =%s", subp)
+                found[arch] = dmi.read_dmi_data(dmi_name)
+        self.assertEqual(expected, found)
+
+    def test_none_returned_if_neither_source_has_data(self):
+        self.patch_mapping({})
+        self._configure_dmidecode_return('key', 'value')
+        self.assertIsNone(dmi.read_dmi_data('expect-fail'))
+
+    def test_none_returned_if_dmidecode_not_in_path(self):
+        self.patched_funcs.enter_context(
+            mock.patch.object(subp, 'which', lambda _: False))
+        self.patch_mapping({})
+        self.assertIsNone(dmi.read_dmi_data('expect-fail'))
+
+    def test_empty_string_returned_instead_of_foxfox(self):
+        # uninitialized dmi values show as \xff, return empty string
+        my_len = 32
+        dmi_value = b'\xff' * my_len + b'\n'
+        expected = ""
+        dmi_key = 'system-product-name'
+        sysfs_key = 'product_name'
+        self._create_sysfs_file(sysfs_key, dmi_value)
+        self.assertEqual(expected, dmi.read_dmi_data(dmi_key))
+
+    def test_container_returns_none(self):
+        """In a container read_dmi_data should always return None."""
+
+        # first verify we get the value if not in container
+        self._m_is_container.return_value = False
+        key, val = ("system-product-name", "my_product")
+        self._create_sysfs_file('product_name', val)
+        self.assertEqual(val, dmi.read_dmi_data(key))
+
+        # then verify in container returns None
+        self._m_is_container.return_value = True
+        self.assertIsNone(dmi.read_dmi_data(key))
+
+    def test_container_returns_none_on_unknown(self):
+        """In a container even bogus keys return None."""
+        self._m_is_container.return_value = True
+        self._create_sysfs_file('product_name', "should-be-ignored")
+        self.assertIsNone(dmi.read_dmi_data("bogus"))
+        self.assertIsNone(dmi.read_dmi_data("system-product-name"))
diff --git a/cloudinit/util.py b/cloudinit/util.py
index b8856af1..bdb3694d 100644
--- a/cloudinit/util.py
+++ b/cloudinit/util.py
@@ -159,32 +159,6 @@ def fully_decoded_payload(part):
     return cte_payload
 
 
-# Path for DMI Data
-DMI_SYS_PATH = "/sys/class/dmi/id"
-
-# dmidecode and /sys/class/dmi/id/* use different names for the same value,
-# this allows us to refer to them by one canonical name
-DMIDECODE_TO_DMI_SYS_MAPPING = {
-    'baseboard-asset-tag': 'board_asset_tag',
-    'baseboard-manufacturer': 'board_vendor',
-    'baseboard-product-name': 'board_name',
-    'baseboard-serial-number': 'board_serial',
-    'baseboard-version': 'board_version',
-    'bios-release-date': 'bios_date',
-    'bios-vendor': 'bios_vendor',
-    'bios-version': 'bios_version',
-    'chassis-asset-tag': 'chassis_asset_tag',
-    'chassis-manufacturer': 'chassis_vendor',
-    'chassis-serial-number': 'chassis_serial',
-    'chassis-version': 'chassis_version',
-    'system-manufacturer': 'sys_vendor',
-    'system-product-name': 'product_name',
-    'system-serial-number': 'product_serial',
-    'system-uuid': 'product_uuid',
-    'system-version': 'product_version',
-}
-
-
 class SeLinuxGuard(object):
     def __init__(self, path, recursive=False):
         # Late import since it might not always
@@ -2421,57 +2395,6 @@ def human2bytes(size):
     return int(num * mpliers[mplier])
 
 
-def _read_dmi_syspath(key):
-    """
-    Reads dmi data with from /sys/class/dmi/id
-    """
-    if key not in DMIDECODE_TO_DMI_SYS_MAPPING:
-        return None
-    mapped_key = DMIDECODE_TO_DMI_SYS_MAPPING[key]
-    dmi_key_path = "{0}/{1}".format(DMI_SYS_PATH, mapped_key)
-    LOG.debug("querying dmi data %s", dmi_key_path)
-    try:
-        if not os.path.exists(dmi_key_path):
-            LOG.debug("did not find %s", dmi_key_path)
-            return None
-
-        key_data = load_file(dmi_key_path, decode=False)
-        if not key_data:
-            LOG.debug("%s did not return any data", dmi_key_path)
-            return None
-
-        # uninitialized dmi values show as all \xff and /sys appends a '\n'.
-        # in that event, return a string of '.' in the same length.
-        if key_data == b'\xff' * (len(key_data) - 1) + b'\n':
-            key_data = b""
-
-        str_data = key_data.decode('utf8').strip()
-        LOG.debug("dmi data %s returned %s", dmi_key_path, str_data)
-        return str_data
-
-    except Exception:
-        logexc(LOG, "failed read of %s", dmi_key_path)
-        return None
-
-
-def _call_dmidecode(key, dmidecode_path):
-    """
-    Calls out to dmidecode to get the data out. This is mostly for supporting
-    OS's without /sys/class/dmi/id support.
-    """
-    try:
-        cmd = [dmidecode_path, "--string", key]
-        (result, _err) = subp.subp(cmd)
-        result = result.strip()
-        LOG.debug("dmidecode returned '%s' for '%s'", result, key)
-        if result.replace(".", "") == "":
-            return ""
-        return result
-    except (IOError, OSError) as e:
-        LOG.debug('failed dmidecode cmd: %s\n%s', cmd, e)
-        return None
-
-
 def is_x86(uname_arch=None):
     """Return True if platform is x86-based"""
     if uname_arch is None:
@@ -2482,48 +2405,6 @@ def is_x86(uname_arch=None):
     return x86_arch_match
 
 
-def read_dmi_data(key):
-    """
-    Wrapper for reading DMI data.
-
-    If running in a container return None.  This is because DMI data is
-    assumed to be not useful in a container as it does not represent the
-    container but rather the host.
-
-    This will do the following (returning the first that produces a
-    result):
-        1) Use a mapping to translate `key` from dmidecode naming to
-           sysfs naming and look in /sys/class/dmi/... for a value.
-        2) Use `key` as a sysfs key directly and look in /sys/class/dmi/...
-        3) Fall-back to passing `key` to `dmidecode --string`.
-
-    If all of the above fail to find a value, None will be returned.
-    """
-
-    if is_container():
-        return None
-
-    syspath_value = _read_dmi_syspath(key)
-    if syspath_value is not None:
-        return syspath_value
-
-    # running dmidecode can be problematic on some arches (LP: #1243287)
-    uname_arch = os.uname()[4]
-    if not (is_x86(uname_arch) or
-            uname_arch == 'aarch64' or
-            uname_arch == 'amd64'):
-        LOG.debug("dmidata is not supported on %s", uname_arch)
-        return None
-
-    dmidecode_path = subp.which('dmidecode')
-    if dmidecode_path:
-        return _call_dmidecode(key, dmidecode_path)
-
-    LOG.warning("did not find either path %s or dmidecode command",
-                DMI_SYS_PATH)
-    return None
-
-
 def message_from_string(string):
     if sys.version_info[:2] < (2, 7):
         return email.message_from_file(io.StringIO(string))
diff --git a/tests/unittests/test_datasource/test_aliyun.py b/tests/unittests/test_datasource/test_aliyun.py
index b626229e..eb2828d5 100644
--- a/tests/unittests/test_datasource/test_aliyun.py
+++ b/tests/unittests/test_datasource/test_aliyun.py
@@ -188,7 +188,7 @@ class TestIsAliYun(test_helpers.CiTestCase):
     ALIYUN_PRODUCT = 'Alibaba Cloud ECS'
     read_dmi_data_expected = [mock.call('system-product-name')]
 
-    @mock.patch("cloudinit.sources.DataSourceAliYun.util.read_dmi_data")
+    @mock.patch("cloudinit.sources.DataSourceAliYun.dmi.read_dmi_data")
     def test_true_on_aliyun_product(self, m_read_dmi_data):
         """Should return true if the dmi product data has expected value."""
         m_read_dmi_data.return_value = self.ALIYUN_PRODUCT
@@ -197,7 +197,7 @@ class TestIsAliYun(test_helpers.CiTestCase):
                          m_read_dmi_data.call_args_list)
         self.assertEqual(True, ret)
 
-    @mock.patch("cloudinit.sources.DataSourceAliYun.util.read_dmi_data")
+    @mock.patch("cloudinit.sources.DataSourceAliYun.dmi.read_dmi_data")
     def test_false_on_empty_string(self, m_read_dmi_data):
         """Should return false on empty value returned."""
         m_read_dmi_data.return_value = ""
@@ -206,7 +206,7 @@ class TestIsAliYun(test_helpers.CiTestCase):
                          m_read_dmi_data.call_args_list)
         self.assertEqual(False, ret)
 
-    @mock.patch("cloudinit.sources.DataSourceAliYun.util.read_dmi_data")
+    @mock.patch("cloudinit.sources.DataSourceAliYun.dmi.read_dmi_data")
     def test_false_on_unknown_string(self, m_read_dmi_data):
         """Should return false on an unrelated string."""
         m_read_dmi_data.return_value = "cubs win"
diff --git a/tests/unittests/test_datasource/test_altcloud.py b/tests/unittests/test_datasource/test_altcloud.py
index fc59d1d5..7a5393ac 100644
--- a/tests/unittests/test_datasource/test_altcloud.py
+++ b/tests/unittests/test_datasource/test_altcloud.py
@@ -14,6 +14,7 @@ import os
 import shutil
 import tempfile
 
+from cloudinit import dmi
 from cloudinit import helpers
 from cloudinit import subp
 from cloudinit import util
@@ -88,14 +89,14 @@ class TestGetCloudType(CiTestCase):
         super(TestGetCloudType, self).setUp()
         self.tmp = self.tmp_dir()
         self.paths = helpers.Paths({'cloud_dir': self.tmp})
-        self.dmi_data = util.read_dmi_data
+        self.dmi_data = dmi.read_dmi_data
         # We have a different code path for arm to deal with LP1243287
         # We have to switch arch to x86_64 to avoid test failure
         force_arch('x86_64')
 
     def tearDown(self):
         # Reset
-        util.read_dmi_data = self.dmi_data
+        dmi.read_dmi_data = self.dmi_data
         force_arch()
 
     def test_cloud_info_file_ioerror(self):
@@ -123,7 +124,7 @@ class TestGetCloudType(CiTestCase):
         Test method get_cloud_type() for RHEVm systems.
         Forcing read_dmi_data return to match a RHEVm system: RHEV Hypervisor
         '''
-        util.read_dmi_data = _dmi_data('RHEV')
+        dmi.read_dmi_data = _dmi_data('RHEV')
         dsrc = dsac.DataSourceAltCloud({}, None, self.paths)
         self.assertEqual('RHEV', dsrc.get_cloud_type())
 
@@ -132,7 +133,7 @@ class TestGetCloudType(CiTestCase):
         Test method get_cloud_type() for vSphere systems.
         Forcing read_dmi_data return to match a vSphere system: RHEV Hypervisor
         '''
-        util.read_dmi_data = _dmi_data('VMware Virtual Platform')
+        dmi.read_dmi_data = _dmi_data('VMware Virtual Platform')
         dsrc = dsac.DataSourceAltCloud({}, None, self.paths)
         self.assertEqual('VSPHERE', dsrc.get_cloud_type())
 
@@ -141,7 +142,7 @@ class TestGetCloudType(CiTestCase):
         Test method get_cloud_type() for unknown systems.
         Forcing read_dmi_data return to match an unrecognized return.
         '''
-        util.read_dmi_data = _dmi_data('Unrecognized Platform')
+        dmi.read_dmi_data = _dmi_data('Unrecognized Platform')
         dsrc = dsac.DataSourceAltCloud({}, None, self.paths)
         self.assertEqual('UNKNOWN', dsrc.get_cloud_type())
 
@@ -219,7 +220,7 @@ class TestGetDataNoCloudInfoFile(CiTestCase):
         self.tmp = self.tmp_dir()
         self.paths = helpers.Paths(
             {'cloud_dir': self.tmp, 'run_dir': self.tmp})
-        self.dmi_data = util.read_dmi_data
+        self.dmi_data = dmi.read_dmi_data
         dsac.CLOUD_INFO_FILE = \
             'no such file'
         # We have a different code path for arm to deal with LP1243287
@@ -230,14 +231,14 @@ class TestGetDataNoCloudInfoFile(CiTestCase):
         # Reset
         dsac.CLOUD_INFO_FILE = \
             '/etc/sysconfig/cloud-info'
-        util.read_dmi_data = self.dmi_data
+        dmi.read_dmi_data = self.dmi_data
         # Return back to original arch
         force_arch()
 
     def test_rhev_no_cloud_file(self):
         '''Test No cloud info file module get_data() forcing RHEV.'''
 
-        util.read_dmi_data = _dmi_data('RHEV Hypervisor')
+        dmi.read_dmi_data = _dmi_data('RHEV Hypervisor')
         dsrc = dsac.DataSourceAltCloud({}, None, self.paths)
         dsrc.user_data_rhevm = lambda: True
         self.assertEqual(True, dsrc.get_data())
@@ -245,7 +246,7 @@ class TestGetDataNoCloudInfoFile(CiTestCase):
     def test_vsphere_no_cloud_file(self):
         '''Test No cloud info file module get_data() forcing VSPHERE.'''
 
-        util.read_dmi_data = _dmi_data('VMware Virtual Platform')
+        dmi.read_dmi_data = _dmi_data('VMware Virtual Platform')
         dsrc = dsac.DataSourceAltCloud({}, None, self.paths)
         dsrc.user_data_vsphere = lambda: True
         self.assertEqual(True, dsrc.get_data())
@@ -253,7 +254,7 @@ class TestGetDataNoCloudInfoFile(CiTestCase):
     def test_failure_no_cloud_file(self):
         '''Test No cloud info file module get_data() forcing unrecognized.'''
 
-        util.read_dmi_data = _dmi_data('Unrecognized Platform')
+        dmi.read_dmi_data = _dmi_data('Unrecognized Platform')
         dsrc = dsac.DataSourceAltCloud({}, None, self.paths)
         self.assertEqual(False, dsrc.get_data())
 
diff --git a/tests/unittests/test_datasource/test_azure.py b/tests/unittests/test_datasource/test_azure.py
index 56c1cf18..433fbc66 100644
--- a/tests/unittests/test_datasource/test_azure.py
+++ b/tests/unittests/test_datasource/test_azure.py
@@ -570,7 +570,7 @@ scbus-1 on xpt0 bus 0
             (dsaz, 'set_hostname', mock.MagicMock()),
             (dsaz, 'get_metadata_from_fabric', self.get_metadata_from_fabric),
             (dsaz.subp, 'which', lambda x: True),
-            (dsaz.util, 'read_dmi_data', mock.MagicMock(
+            (dsaz.dmi, 'read_dmi_data', mock.MagicMock(
                 side_effect=_dmi_mocks)),
             (dsaz.util, 'wait_for_files', mock.MagicMock(
                 side_effect=_wait_for_files)),
@@ -1427,7 +1427,7 @@ class TestAzureBounce(CiTestCase):
             raise RuntimeError('should not get here')
 
         self.patches.enter_context(
-            mock.patch.object(dsaz.util, 'read_dmi_data',
+            mock.patch.object(dsaz.dmi, 'read_dmi_data',
                               mock.MagicMock(side_effect=_dmi_mocks)))
 
     def setUp(self):
@@ -2294,14 +2294,14 @@ class TestWBIsPlatformViable(CiTestCase):
     """White box tests for _is_platform_viable."""
     with_logs = True
 
-    @mock.patch(MOCKPATH + 'util.read_dmi_data')
+    @mock.patch(MOCKPATH + 'dmi.read_dmi_data')
     def test_true_on_non_azure_chassis(self, m_read_dmi_data):
         """Return True if DMI chassis-asset-tag is AZURE_CHASSIS_ASSET_TAG."""
         m_read_dmi_data.return_value = dsaz.AZURE_CHASSIS_ASSET_TAG
         self.assertTrue(dsaz._is_platform_viable('doesnotmatter'))
 
     @mock.patch(MOCKPATH + 'os.path.exists')
-    @mock.patch(MOCKPATH + 'util.read_dmi_data')
+    @mock.patch(MOCKPATH + 'dmi.read_dmi_data')
     def test_true_on_azure_ovf_env_in_seed_dir(self, m_read_dmi_data, m_exist):
         """Return True if ovf-env.xml exists in known seed dirs."""
         # Non-matching Azure chassis-asset-tag
@@ -2322,7 +2322,7 @@ class TestWBIsPlatformViable(CiTestCase):
             MOCKPATH,
             {'os.path.exists': False,
              # Non-matching Azure chassis-asset-tag
-             'util.read_dmi_data': dsaz.AZURE_CHASSIS_ASSET_TAG + 'X',
+             'dmi.read_dmi_data': dsaz.AZURE_CHASSIS_ASSET_TAG + 'X',
              'subp.which': None},
             dsaz._is_platform_viable, 'doesnotmatter'))
         self.assertIn(
diff --git a/tests/unittests/test_datasource/test_nocloud.py b/tests/unittests/test_datasource/test_nocloud.py
index 2e6b53ff..02cc9b38 100644
--- a/tests/unittests/test_datasource/test_nocloud.py
+++ b/tests/unittests/test_datasource/test_nocloud.py
@@ -1,5 +1,6 @@
 # This file is part of cloud-init. See LICENSE file for license information.
 
+from cloudinit import dmi
 from cloudinit import helpers
 from cloudinit.sources.DataSourceNoCloud import (
     DataSourceNoCloud as dsNoCloud,
@@ -30,7 +31,7 @@ class TestNoCloudDataSource(CiTestCase):
         self.mocks.enter_context(
             mock.patch.object(util, 'get_cmdline', return_value=self.cmdline))
         self.mocks.enter_context(
-            mock.patch.object(util, 'read_dmi_data', return_value=None))
+            mock.patch.object(dmi, 'read_dmi_data', return_value=None))
 
     def _test_fs_config_is_read(self, fs_label, fs_label_to_search):
         vfat_device = 'device-1'
diff --git a/tests/unittests/test_datasource/test_openstack.py b/tests/unittests/test_datasource/test_openstack.py
index 9b0c1b8a..415755aa 100644
--- a/tests/unittests/test_datasource/test_openstack.py
+++ b/tests/unittests/test_datasource/test_openstack.py
@@ -459,7 +459,7 @@ class TestDetectOpenStack(test_helpers.CiTestCase):
             ds.detect_openstack(), 'Expected detect_openstack == True')
 
     @test_helpers.mock.patch(MOCK_PATH + 'util.get_proc_env')
-    @test_helpers.mock.patch(MOCK_PATH + 'util.read_dmi_data')
+    @test_helpers.mock.patch(MOCK_PATH + 'dmi.read_dmi_data')
     def test_not_detect_openstack_intel_x86_ec2(self, m_dmi, m_proc_env,
                                                 m_is_x86):
         """Return False on EC2 platforms."""
@@ -479,7 +479,7 @@ class TestDetectOpenStack(test_helpers.CiTestCase):
             ds.detect_openstack(), 'Expected detect_openstack == False on EC2')
         m_proc_env.assert_called_with(1)
 
-    @test_helpers.mock.patch(MOCK_PATH + 'util.read_dmi_data')
+    @test_helpers.mock.patch(MOCK_PATH + 'dmi.read_dmi_data')
     def test_detect_openstack_intel_product_name_compute(self, m_dmi,
                                                          m_is_x86):
         """Return True on OpenStack compute and nova instances."""
@@ -491,7 +491,7 @@ class TestDetectOpenStack(test_helpers.CiTestCase):
             self.assertTrue(
                 ds.detect_openstack(), 'Failed to detect_openstack')
 
-    @test_helpers.mock.patch(MOCK_PATH + 'util.read_dmi_data')
+    @test_helpers.mock.patch(MOCK_PATH + 'dmi.read_dmi_data')
     def test_detect_openstack_opentelekomcloud_chassis_asset_tag(self, m_dmi,
                                                                  m_is_x86):
         """Return True on OpenStack reporting OpenTelekomCloud asset-tag."""
@@ -509,7 +509,7 @@ class TestDetectOpenStack(test_helpers.CiTestCase):
             ds.detect_openstack(),
             'Expected detect_openstack == True on OpenTelekomCloud')
 
-    @test_helpers.mock.patch(MOCK_PATH + 'util.read_dmi_data')
+    @test_helpers.mock.patch(MOCK_PATH + 'dmi.read_dmi_data')
     def test_detect_openstack_sapccloud_chassis_asset_tag(self, m_dmi,
                                                           m_is_x86):
         """Return True on OpenStack reporting SAP CCloud VM asset-tag."""
@@ -527,7 +527,7 @@ class TestDetectOpenStack(test_helpers.CiTestCase):
             ds.detect_openstack(),
             'Expected detect_openstack == True on SAP CCloud VM')
 
-    @test_helpers.mock.patch(MOCK_PATH + 'util.read_dmi_data')
+    @test_helpers.mock.patch(MOCK_PATH + 'dmi.read_dmi_data')
     def test_detect_openstack_oraclecloud_chassis_asset_tag(self, m_dmi,
                                                             m_is_x86):
         """Return True on OpenStack reporting Oracle cloud asset-tag."""
@@ -566,20 +566,20 @@ class TestDetectOpenStack(test_helpers.CiTestCase):
             ds.detect_openstack(),
             'Expected detect_openstack == True on Generic OpenStack Platform')
 
-    @test_helpers.mock.patch(MOCK_PATH + 'util.read_dmi_data')
+    @test_helpers.mock.patch(MOCK_PATH + 'dmi.read_dmi_data')
     def test_detect_openstack_nova_chassis_asset_tag(self, m_dmi,
                                                      m_is_x86):
         self._test_detect_openstack_nova_compute_chassis_asset_tag(
             m_dmi, m_is_x86, 'OpenStack Nova')
 
-    @test_helpers.mock.patch(MOCK_PATH + 'util.read_dmi_data')
+    @test_helpers.mock.patch(MOCK_PATH + 'dmi.read_dmi_data')
     def test_detect_openstack_compute_chassis_asset_tag(self, m_dmi,
                                                         m_is_x86):
         self._test_detect_openstack_nova_compute_chassis_asset_tag(
             m_dmi, m_is_x86, 'OpenStack Compute')
 
     @test_helpers.mock.patch(MOCK_PATH + 'util.get_proc_env')
-    @test_helpers.mock.patch(MOCK_PATH + 'util.read_dmi_data')
+    @test_helpers.mock.patch(MOCK_PATH + 'dmi.read_dmi_data')
     def test_detect_openstack_by_proc_1_environ(self, m_dmi, m_proc_env,
                                                 m_is_x86):
         """Return True when nova product_name specified in /proc/1/environ."""
diff --git a/tests/unittests/test_datasource/test_ovf.py b/tests/unittests/test_datasource/test_ovf.py
index 1d088577..16773de5 100644
--- a/tests/unittests/test_datasource/test_ovf.py
+++ b/tests/unittests/test_datasource/test_ovf.py
@@ -129,7 +129,7 @@ class TestDatasourceOVF(CiTestCase):
         ds = self.datasource(sys_cfg={}, distro={}, paths=paths)
         retcode = wrap_and_call(
             'cloudinit.sources.DataSourceOVF',
-            {'util.read_dmi_data': None,
+            {'dmi.read_dmi_data': None,
              'transport_iso9660': NOT_FOUND,
              'transport_vmware_guestinfo': NOT_FOUND},
             ds.get_data)
@@ -145,7 +145,7 @@ class TestDatasourceOVF(CiTestCase):
             paths=paths)
         retcode = wrap_and_call(
             'cloudinit.sources.DataSourceOVF',
-            {'util.read_dmi_data': 'vmware',
+            {'dmi.read_dmi_data': 'vmware',
              'transport_iso9660': NOT_FOUND,
              'transport_vmware_guestinfo': NOT_FOUND},
             ds.get_data)
@@ -174,7 +174,7 @@ class TestDatasourceOVF(CiTestCase):
             with self.assertRaises(CustomScriptNotFound) as context:
                 wrap_and_call(
                     'cloudinit.sources.DataSourceOVF',
-                    {'util.read_dmi_data': 'vmware',
+                    {'dmi.read_dmi_data': 'vmware',
                      'util.del_dir': True,
                      'search_file': self.tdir,
                      'wait_for_imc_cfg_file': conf_file,
@@ -211,7 +211,7 @@ class TestDatasourceOVF(CiTestCase):
                 with self.assertRaises(RuntimeError) as context:
                     wrap_and_call(
                         'cloudinit.sources.DataSourceOVF',
-                        {'util.read_dmi_data': 'vmware',
+                        {'dmi.read_dmi_data': 'vmware',
                          'util.del_dir': True,
                          'search_file': self.tdir,
                          'wait_for_imc_cfg_file': conf_file,
@@ -246,7 +246,7 @@ class TestDatasourceOVF(CiTestCase):
                 with self.assertRaises(CustomScriptNotFound) as context:
                     wrap_and_call(
                         'cloudinit.sources.DataSourceOVF',
-                        {'util.read_dmi_data': 'vmware',
+                        {'dmi.read_dmi_data': 'vmware',
                          'util.del_dir': True,
                          'search_file': self.tdir,
                          'wait_for_imc_cfg_file': conf_file,
@@ -290,7 +290,7 @@ class TestDatasourceOVF(CiTestCase):
                 with self.assertRaises(CustomScriptNotFound) as context:
                     wrap_and_call(
                         'cloudinit.sources.DataSourceOVF',
-                        {'util.read_dmi_data': 'vmware',
+                        {'dmi.read_dmi_data': 'vmware',
                          'util.del_dir': True,
                          'search_file': self.tdir,
                          'wait_for_imc_cfg_file': conf_file,
@@ -313,7 +313,7 @@ class TestDatasourceOVF(CiTestCase):
 
         self.assertEqual('ovf', ds.cloud_name)
         self.assertEqual('ovf', ds.platform_type)
-        with mock.patch(MPATH + 'util.read_dmi_data', return_value='!VMware'):
+        with mock.patch(MPATH + 'dmi.read_dmi_data', return_value='!VMware'):
             with mock.patch(MPATH + 'transport_vmware_guestinfo') as m_guestd:
                 with mock.patch(MPATH + 'transport_iso9660') as m_iso9660:
                     m_iso9660.return_value = NOT_FOUND
@@ -334,7 +334,7 @@ class TestDatasourceOVF(CiTestCase):
 
         self.assertEqual('ovf', ds.cloud_name)
         self.assertEqual('ovf', ds.platform_type)
-        with mock.patch(MPATH + 'util.read_dmi_data', return_value='VMWare'):
+        with mock.patch(MPATH + 'dmi.read_dmi_data', return_value='VMWare'):
             with mock.patch(MPATH + 'transport_vmware_guestinfo') as m_guestd:
                 with mock.patch(MPATH + 'transport_iso9660') as m_iso9660:
                     m_iso9660.return_value = NOT_FOUND
diff --git a/tests/unittests/test_datasource/test_scaleway.py b/tests/unittests/test_datasource/test_scaleway.py
index 9d82bda9..32f3274a 100644
--- a/tests/unittests/test_datasource/test_scaleway.py
+++ b/tests/unittests/test_datasource/test_scaleway.py
@@ -87,7 +87,7 @@ class TestOnScaleway(CiTestCase):
 
     @mock.patch('cloudinit.util.get_cmdline')
     @mock.patch('os.path.exists')
-    @mock.patch('cloudinit.util.read_dmi_data')
+    @mock.patch('cloudinit.dmi.read_dmi_data')
     def test_not_on_scaleway(self, m_read_dmi_data, m_file_exists,
                              m_get_cmdline):
         self.install_mocks(
@@ -105,7 +105,7 @@ class TestOnScaleway(CiTestCase):
 
     @mock.patch('cloudinit.util.get_cmdline')
     @mock.patch('os.path.exists')
-    @mock.patch('cloudinit.util.read_dmi_data')
+    @mock.patch('cloudinit.dmi.read_dmi_data')
     def test_on_scaleway_dmi(self, m_read_dmi_data, m_file_exists,
                              m_get_cmdline):
         """
@@ -121,7 +121,7 @@ class TestOnScaleway(CiTestCase):
 
     @mock.patch('cloudinit.util.get_cmdline')
     @mock.patch('os.path.exists')
-    @mock.patch('cloudinit.util.read_dmi_data')
+    @mock.patch('cloudinit.dmi.read_dmi_data')
     def test_on_scaleway_var_run_scaleway(self, m_read_dmi_data, m_file_exists,
                                           m_get_cmdline):
         """
@@ -136,7 +136,7 @@ class TestOnScaleway(CiTestCase):
 
     @mock.patch('cloudinit.util.get_cmdline')
     @mock.patch('os.path.exists')
-    @mock.patch('cloudinit.util.read_dmi_data')
+    @mock.patch('cloudinit.dmi.read_dmi_data')
     def test_on_scaleway_cmdline(self, m_read_dmi_data, m_file_exists,
                                  m_get_cmdline):
         """
diff --git a/tests/unittests/test_util.py b/tests/unittests/test_util.py
index cca53123..857629f1 100644
--- a/tests/unittests/test_util.py
+++ b/tests/unittests/test_util.py
@@ -492,129 +492,6 @@ class TestIsX86(helpers.CiTestCase):
         self.assertTrue(util.is_x86())
 
 
-class TestReadDMIData(helpers.FilesystemMockingTestCase):
-
-    def setUp(self):
-        super(TestReadDMIData, self).setUp()
-        self.new_root = tempfile.mkdtemp()
-        self.addCleanup(shutil.rmtree, self.new_root)
-        self.patchOS(self.new_root)
-        self.patchUtils(self.new_root)
-        p = mock.patch("cloudinit.util.is_container", return_value=False)
-        self.addCleanup(p.stop)
-        self._m_is_container = p.start()
-
-    def _create_sysfs_parent_directory(self):
-        util.ensure_dir(os.path.join('sys', 'class', 'dmi', 'id'))
-
-    def _create_sysfs_file(self, key, content):
-        """Mocks the sys path found on Linux systems."""
-        self._create_sysfs_parent_directory()
-        dmi_key = "/sys/class/dmi/id/{0}".format(key)
-        util.write_file(dmi_key, content)
-
-    def _configure_dmidecode_return(self, key, content, error=None):
-        """
-        In order to test a missing sys path and call outs to dmidecode, this
-        function fakes the results of dmidecode to test the results.
-        """
-        def _dmidecode_subp(cmd):
-            if cmd[-1] != key:
-                raise subp.ProcessExecutionError()
-            return (content, error)
-
-        self.patched_funcs.enter_context(
-            mock.patch("cloudinit.subp.which", side_effect=lambda _: True))
-        self.patched_funcs.enter_context(
-            mock.patch("cloudinit.subp.subp", side_effect=_dmidecode_subp))
-
-    def patch_mapping(self, new_mapping):
-        self.patched_funcs.enter_context(
-            mock.patch('cloudinit.util.DMIDECODE_TO_DMI_SYS_MAPPING',
-                       new_mapping))
-
-    def test_sysfs_used_with_key_in_mapping_and_file_on_disk(self):
-        self.patch_mapping({'mapped-key': 'mapped-value'})
-        expected_dmi_value = 'sys-used-correctly'
-        self._create_sysfs_file('mapped-value', expected_dmi_value)
-        self._configure_dmidecode_return('mapped-key', 'wrong-wrong-wrong')
-        self.assertEqual(expected_dmi_value, util.read_dmi_data('mapped-key'))
-
-    def test_dmidecode_used_if_no_sysfs_file_on_disk(self):
-        self.patch_mapping({})
-        self._create_sysfs_parent_directory()
-        expected_dmi_value = 'dmidecode-used'
-        self._configure_dmidecode_return('use-dmidecode', expected_dmi_value)
-        with mock.patch("cloudinit.util.os.uname") as m_uname:
-            m_uname.return_value = ('x-sysname', 'x-nodename',
-                                    'x-release', 'x-version', 'x86_64')
-            self.assertEqual(expected_dmi_value,
-                             util.read_dmi_data('use-dmidecode'))
-
-    def test_dmidecode_not_used_on_arm(self):
-        self.patch_mapping({})
-        print("current =%s", subp)
-        self._create_sysfs_parent_directory()
-        dmi_val = 'from-dmidecode'
-        dmi_name = 'use-dmidecode'
-        self._configure_dmidecode_return(dmi_name, dmi_val)
-        print("now =%s", subp)
-
-        expected = {'armel': None, 'aarch64': dmi_val, 'x86_64': dmi_val}
-        found = {}
-        # we do not run the 'dmi-decode' binary on some arches
-        # verify that anything requested that is not in the sysfs dir
-        # will return None on those arches.
-        with mock.patch("cloudinit.util.os.uname") as m_uname:
-            for arch in expected:
-                m_uname.return_value = ('x-sysname', 'x-nodename',
-                                        'x-release', 'x-version', arch)
-                print("now2 =%s", subp)
-                found[arch] = util.read_dmi_data(dmi_name)
-        self.assertEqual(expected, found)
-
-    def test_none_returned_if_neither_source_has_data(self):
-        self.patch_mapping({})
-        self._configure_dmidecode_return('key', 'value')
-        self.assertIsNone(util.read_dmi_data('expect-fail'))
-
-    def test_none_returned_if_dmidecode_not_in_path(self):
-        self.patched_funcs.enter_context(
-            mock.patch.object(subp, 'which', lambda _: False))
-        self.patch_mapping({})
-        self.assertIsNone(util.read_dmi_data('expect-fail'))
-
-    def test_dots_returned_instead_of_foxfox(self):
-        # uninitialized dmi values show as \xff, return those as .
-        my_len = 32
-        dmi_value = b'\xff' * my_len + b'\n'
-        expected = ""
-        dmi_key = 'system-product-name'
-        sysfs_key = 'product_name'
-        self._create_sysfs_file(sysfs_key, dmi_value)
-        self.assertEqual(expected, util.read_dmi_data(dmi_key))
-
-    def test_container_returns_none(self):
-        """In a container read_dmi_data should always return None."""
-
-        # first verify we get the value if not in container
-        self._m_is_container.return_value = False
-        key, val = ("system-product-name", "my_product")
-        self._create_sysfs_file('product_name', val)
-        self.assertEqual(val, util.read_dmi_data(key))
-
-        # then verify in container returns None
-        self._m_is_container.return_value = True
-        self.assertIsNone(util.read_dmi_data(key))
-
-    def test_container_returns_none_on_unknown(self):
-        """In a container even bogus keys return None."""
-        self._m_is_container.return_value = True
-        self._create_sysfs_file('product_name', "should-be-ignored")
-        self.assertIsNone(util.read_dmi_data("bogus"))
-        self.assertIsNone(util.read_dmi_data("system-product-name"))
-
-
 class TestGetConfigLogfiles(helpers.CiTestCase):
 
     def test_empty_cfg_returns_empty_list(self):