diff --git a/pungi/phases/buildinstall.py b/pungi/phases/buildinstall.py
index c75020af..b10384de 100644
--- a/pungi/phases/buildinstall.py
+++ b/pungi/phases/buildinstall.py
@@ -27,7 +27,7 @@ from productmd.images import Image
 
 from pungi.arch import get_valid_arches
 from pungi.util import get_buildroot_rpms, get_volid, get_arch_variant_data
-from pungi.util import get_file_size, get_mtime, failable, makedirs
+from pungi.util import get_file_size, get_mtime, failable, makedirs, run_unmount_cmd
 from pungi.wrappers.lorax import LoraxWrapper
 from pungi.wrappers.kojiwrapper import KojiWrapper
 from pungi.wrappers import iso
@@ -273,8 +273,7 @@ def tweak_buildinstall(compose, src, dst, arch, variant, label, volid, kickstart
                 cmd = ["cp", "-v", "--remove-destination", config_path, config_in_image]
                 run(cmd)
 
-        cmd = ["fusermount", "-u", mount_tmp_dir]
-        run(cmd)
+        run_unmount_cmd(["fusermount", "-u", mount_tmp_dir])
         shutil.rmtree(mount_tmp_dir)
 
     # HACK: make buildinstall files world readable
diff --git a/pungi/util.py b/pungi/util.py
index 01cab53c..f98893d4 100644
--- a/pungi/util.py
+++ b/pungi/util.py
@@ -26,6 +26,7 @@ import urlparse
 import contextlib
 import traceback
 import tempfile
+import time
 
 from kobo.shortcuts import run, force_list
 from productmd.common import get_major_version
@@ -592,3 +593,22 @@ def temp_dir(log=None, *args, **kwargs):
             # Okay, we failed to delete temporary dir.
             if log:
                 log.warning('Error removing %s: %s', dir, exc.strerror)
+
+
+def run_unmount_cmd(cmd, max_retries=10):
+    """Attempt to run the command to unmount an image.
+
+    If the command fails and stderr complains about device being busy, try
+    again. We will do up to ``max_retries`` attemps with increasing pauses.
+    """
+    for i in xrange(max_retries):
+        proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        out, err = proc.communicate()
+        if proc.returncode == 0:
+            # We were successful
+            return
+        if 'Device or resource busy' not in err:
+            raise RuntimeError('Unhandled error when running %r: %r' % (cmd, err))
+        time.sleep(i)
+    # Still busy, there's something wrong.
+    raise RuntimeError('Failed to run %r: Device or resource busy.' % cmd)
diff --git a/tests/test_util.py b/tests/test_util.py
index 3052aab5..108b57cc 100644
--- a/tests/test_util.py
+++ b/tests/test_util.py
@@ -10,6 +10,7 @@ except ImportError:
     import unittest
 import tempfile
 import shutil
+import subprocess
 
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
 
@@ -428,5 +429,60 @@ class TestTempFiles(unittest.TestCase):
             self.assertFalse(os.path.exists(tmp))
 
 
+class TestUnmountCmd(unittest.TestCase):
+
+    def _fakeProc(self, ret, err):
+        proc = mock.Mock(returncode=ret)
+        proc.communicate.return_value = ('', err)
+        return proc
+
+    @mock.patch('subprocess.Popen')
+    def test_unmount_cmd_success(self, mockPopen):
+        cmd = 'unmount'
+        mockPopen.side_effect = [self._fakeProc(0, '')]
+        util.run_unmount_cmd(cmd)
+        self.assertEqual(mockPopen.call_args_list,
+                         [mock.call(cmd, stderr=subprocess.PIPE, stdout=subprocess.PIPE)])
+
+    @mock.patch('subprocess.Popen')
+    def test_unmount_cmd_fail_other_reason(self, mockPopen):
+        cmd = 'unmount'
+        mockPopen.side_effect = [self._fakeProc(1, 'It is broken')]
+        with self.assertRaises(RuntimeError) as ctx:
+            util.run_unmount_cmd(cmd)
+        self.assertEqual(str(ctx.exception),
+                         "Unhandled error when running 'unmount': 'It is broken'")
+        self.assertEqual(mockPopen.call_args_list,
+                         [mock.call(cmd, stderr=subprocess.PIPE, stdout=subprocess.PIPE)])
+
+    @mock.patch('time.sleep')
+    @mock.patch('subprocess.Popen')
+    def test_unmount_cmd_fail_then_retry(self, mockPopen, mock_sleep):
+        cmd = 'unmount'
+        mockPopen.side_effect = [self._fakeProc(1, 'Device or resource busy'),
+                                 self._fakeProc(1, 'Device or resource busy'),
+                                 self._fakeProc(0, '')]
+        util.run_unmount_cmd(cmd)
+        self.assertEqual(mockPopen.call_args_list,
+                         [mock.call(cmd, stderr=subprocess.PIPE, stdout=subprocess.PIPE)] * 3)
+        self.assertEqual(mock_sleep.call_args_list,
+                         [mock.call(0), mock.call(1)])
+
+    @mock.patch('time.sleep')
+    @mock.patch('subprocess.Popen')
+    def test_unmount_cmd_fail_then_retry_and_fail(self, mockPopen, mock_sleep):
+        cmd = 'unmount'
+        mockPopen.side_effect = [self._fakeProc(1, 'Device or resource busy'),
+                                 self._fakeProc(1, 'Device or resource busy'),
+                                 self._fakeProc(1, 'Device or resource busy')]
+        with self.assertRaises(RuntimeError) as ctx:
+            util.run_unmount_cmd(cmd, max_retries=3)
+        self.assertEqual(mockPopen.call_args_list,
+                         [mock.call(cmd, stderr=subprocess.PIPE, stdout=subprocess.PIPE)] * 3)
+        self.assertEqual(mock_sleep.call_args_list,
+                         [mock.call(0), mock.call(1), mock.call(2)])
+        self.assertEqual(str(ctx.exception), "Failed to run 'unmount': Device or resource busy.")
+
+
 if __name__ == "__main__":
     unittest.main()