diff --git a/pmb/helpers/mount.py b/pmb/helpers/mount.py
index bea29fa4..472a1d64 100644
--- a/pmb/helpers/mount.py
+++ b/pmb/helpers/mount.py
@@ -93,8 +93,13 @@ def umount_all_list(prefix, source="/proc/mounts"):
             if len(words) < 2:
                 raise RuntimeError("Failed to parse line in " + source + ": " +
                                    line)
-            if words[1].startswith(prefix):
-                ret.append(words[1])
+            mountpoint = words[1]
+            if mountpoint.startswith(prefix):
+                # Remove "\040(deleted)" suffix (#545)
+                deleted_str = r"\040(deleted)"
+                if mountpoint.endswith(deleted_str):
+                    mountpoint = mountpoint[:-len(deleted_str)]
+                ret.append(mountpoint)
     ret.sort(reverse=True)
     return ret
 
diff --git a/test/test_mount.py b/test/test_mount.py
index 75b39fde..13d82aab 100644
--- a/test/test_mount.py
+++ b/test/test_mount.py
@@ -33,6 +33,7 @@ def test_umount_all_list(tmpdir):
         handle.write("source /test/home/pmos/packages\n")
         handle.write("source /test\n")
         handle.write("source /test/proc\n")
+        handle.write("source /test/dev/loop0p2\\040(deleted)\n")
 
     ret = pmb.helpers.mount.umount_all_list("/no/match", fake_mounts)
     assert ret == []
@@ -42,4 +43,4 @@ def test_umount_all_list(tmpdir):
 
     ret = pmb.helpers.mount.umount_all_list("/test", fake_mounts)
     assert ret == ["/test/var/cache", "/test/proc", "/test/home/pmos/packages",
-                   "/test"]
+                   "/test/dev/loop0p2", "/test"]