diff --git a/build.gradle b/build.gradle
index e33079526..a63e09d76 100644
--- a/build.gradle
+++ b/build.gradle
@@ -299,6 +299,7 @@ javadoc {
 task deobfJar(type: Jar) {
     from sourceSets.main.output
     exclude "cofh/**"
+    exclude "mods/**"
     configurations.embedded.each { dep ->
         from(project.zipTree(dep)) {
             exclude 'META-INF', 'META-INF/**'
diff --git a/src/main/resources/assets/opencomputers/loot/OpenOS/bin/cp.lua b/src/main/resources/assets/opencomputers/loot/OpenOS/bin/cp.lua
index 5a15b1cf9..85920d0aa 100644
--- a/src/main/resources/assets/opencomputers/loot/OpenOS/bin/cp.lua
+++ b/src/main/resources/assets/opencomputers/loot/OpenOS/bin/cp.lua
@@ -10,6 +10,7 @@ if #args < 2 then
   io.write(" -u: copy only when the SOURCE file differs from the destination\n")
   io.write("     file or when the destination file is missing.\n")
   io.write(" -v: verbose output.")
+  io.write(" -x: stay on original source file system.")
   return
 end
 
@@ -58,6 +59,15 @@ local function areEqual(path1, path2)
   return result
 end
 
+local function isMount(path)
+  path = fs.canonical(path)
+  for _, mountPath in fs.mounts() do
+    if path == fs.canonical(mountPath) then
+      return true
+    end
+  end
+end
+
 local function recurse(fromPath, toPath)
   status(fromPath, toPath)
   if fs.isDirectory(fromPath) then
@@ -72,6 +82,9 @@ local function recurse(fromPath, toPath)
       -- my real cp always does this, even with -f, -n or -i.
       return nil, "cannot overwrite non-directory `" .. toPath .. "' with directory `" .. fromPath .. "'"
     end
+    if options.x and isMount(fromPath) then
+      return true
+    end
     fs.makeDirectory(toPath)
     for file in fs.list(fromPath) do
       local result, reason = recurse(fs.concat(fromPath, file), fs.concat(toPath, file))
diff --git a/src/main/resources/assets/opencomputers/loot/OpenOS/bin/install.lua b/src/main/resources/assets/opencomputers/loot/OpenOS/bin/install.lua
index 0ded2c5b1..25367c286 100644
--- a/src/main/resources/assets/opencomputers/loot/OpenOS/bin/install.lua
+++ b/src/main/resources/assets/opencomputers/loot/OpenOS/bin/install.lua
@@ -59,7 +59,7 @@ local name = options.name or "OpenOS"
 io.write("Installing " .. name .." to device " .. (choice.getLabel() or choice.address) .. "\n")
 os.sleep(0.25)
 local cpPath = filesystem.concat(findMount(filesystem.get(os.getenv("_")).address), "bin/cp")
-local cpOptions = "-vr" .. (options.u and "ui " or "")
+local cpOptions = "-vrx" .. (options.u and "ui " or "")
 local cpSource = filesystem.concat(findMount(fromAddress), options.fromDir or "/", "*")
 local cpDest = findMount(choice.address) .. "/"
 local result, reason = os.execute(cpPath .. " " .. cpOptions .. " " .. cpSource .. " " .. cpDest)