diff --git a/neutron/db/db_base_plugin_v2.py b/neutron/db/db_base_plugin_v2.py
index 6364c90bd63..0b56b6cce88 100644
--- a/neutron/db/db_base_plugin_v2.py
+++ b/neutron/db/db_base_plugin_v2.py
@@ -1524,13 +1524,6 @@ class NeutronDbPluginV2(db_base_plugin_common.DbBasePluginCommon,
                     old_port_db=db_port,
                     old_port=self._make_port_dict(db_port),
                     new_port=new_port)
-            except ipam_exc.IpAddressAllocationNotFound as e:
-                # If a port update and a subnet delete interleave, there is a
-                # chance that the IPAM update operation raises this exception.
-                # Rather than throwing that up to the user under some sort of
-                # conflict, bubble up a retry instead that should bring things
-                # back to sanity.
-                raise os_db_exc.RetryRequest(e)
             except ipam_exc.IPAddressChangeNotAllowed as e:
                 raise exc.BadRequest(resource='ports', msg=e)
         return self._make_port_dict(db_port)
diff --git a/neutron/ipam/drivers/neutrondb_ipam/driver.py b/neutron/ipam/drivers/neutrondb_ipam/driver.py
index a49cafcb7ca..2641ce09566 100644
--- a/neutron/ipam/drivers/neutrondb_ipam/driver.py
+++ b/neutron/ipam/drivers/neutrondb_ipam/driver.py
@@ -281,14 +281,8 @@ class NeutronDbSubnet(ipam_base.Subnet):
     def deallocate(self, address):
         # This is almost a no-op because the Neutron DB IPAM driver does not
         # delete IPAllocation objects at every deallocation. The only
-        # operation it performs is to delete an IPRequest entry.
-        count = self.subnet_manager.delete_allocation(
-            self._context, address)
-        # count can hardly be greater than 1, but it can be 0...
-        if not count:
-            raise ipam_exc.IpAddressAllocationNotFound(
-                subnet_id=self.subnet_manager.neutron_id,
-                ip_address=address)
+        # operation it performs is to delete an IPAMAllocation entry.
+        self.subnet_manager.delete_allocation(self._context, address)
 
     def _no_pool_changes(self, context, pools):
         """Check if pool updates in db are required."""
diff --git a/neutron/ipam/exceptions.py b/neutron/ipam/exceptions.py
index badeef82b4e..d8f351ec990 100644
--- a/neutron/ipam/exceptions.py
+++ b/neutron/ipam/exceptions.py
@@ -31,11 +31,6 @@ class InvalidAddressType(exceptions.NeutronException):
     message = _("Unknown address type %(address_type)s")
 
 
-class IpAddressAllocationNotFound(exceptions.NeutronException):
-    message = _("Unable to find IP address %(ip_address)s on subnet "
-                "%(subnet_id)s")
-
-
 class IpAddressAlreadyAllocated(exceptions.Conflict):
     message = _("IP address %(ip)s already allocated in subnet %(subnet_id)s")
 
diff --git a/neutron/tests/unit/db/test_db_base_plugin_v2.py b/neutron/tests/unit/db/test_db_base_plugin_v2.py
index 9478e4e24c1..07878f852d1 100644
--- a/neutron/tests/unit/db/test_db_base_plugin_v2.py
+++ b/neutron/tests/unit/db/test_db_base_plugin_v2.py
@@ -1498,22 +1498,6 @@ fixed_ips=ip_address%%3D%s&fixed_ips=ip_address%%3D%s&fixed_ips=subnet_id%%3D%s
             res = req.get_response(self.api)
             self.assertEqual(webob.exc.HTTPNotFound.code, res.status_int)
 
-    def test_port_update_with_ipam_error(self):
-        with self.network() as network,\
-                self.subnet(), self.subnet(),\
-                self.port(network=network) as port,\
-                mock.patch('neutron.ipam.drivers.neutrondb_ipam.'
-                           'driver.NeutronDbSubnet.deallocate') as f:
-            f.side_effect = [
-                ipam_exc.IpAddressAllocationNotFound(
-                    ip_address='foo_i', subnet_id='foo_s'),
-                None,
-            ]
-            data = {'port': {'name': 'fool-me'}}
-            req = self.new_update_request('ports', data, port['port']['id'])
-            res = self.deserialize(self.fmt, req.get_response(self.api))
-            self.assertEqual('fool-me', res['port']['name'])
-
     def test_update_port(self):
         with self.port() as port:
             data = {'port': {'admin_state_up': False}}
diff --git a/neutron/tests/unit/ipam/drivers/neutrondb_ipam/test_driver.py b/neutron/tests/unit/ipam/drivers/neutrondb_ipam/test_driver.py
index 2fe3bf35a92..e5df5e58349 100644
--- a/neutron/tests/unit/ipam/drivers/neutrondb_ipam/test_driver.py
+++ b/neutron/tests/unit/ipam/drivers/neutrondb_ipam/test_driver.py
@@ -423,12 +423,6 @@ class TestNeutronDbIpamSubnet(testlib_api.SqlTestCase,
         # future proofing in case v6-specific logic will be added.
         self._test_deallocate_address('fde3:abcd:4321:1::/64', 6)
 
-    def test_allocate_unallocated_address_fails(self):
-        ipam_subnet = self._create_and_allocate_ipam_subnet(
-            '10.0.0.0/24', ip_version=constants.IP_VERSION_4)[0]
-        self.assertRaises(ipam_exc.IpAddressAllocationNotFound,
-                          ipam_subnet.deallocate, '10.0.0.2')
-
     def test_allocate_all_pool_addresses_triggers_range_recalculation(self):
         # This test instead might be made to pass, but for the wrong reasons!
         pass