Add 'enable' action to 'kernel_module' resource to reverse 'disable' action. Fixes #12104

Signed-off-by: qubitrenegade <qubitrenegade@gmail.com>

2 files changed, 29 insertions, 3 deletions

diff --git a/lib/chef/resource/kernel_module.rb b/lib/chef/resource/kernel_module.rb
index c4a36af9eb..6f548d8363 100644
--- a/lib/chef/resource/kernel_module.rb
+++ b/lib/chef/resource/kernel_module.rb
@@ -15,7 +15,7 @@ class Chef
 
       provides :kernel_module
 
-      description "Use the **kernel_module** resource to manage kernel modules on Linux systems. This resource can load, unload, blacklist, disable, install, and uninstall modules."
+      description "Use the **kernel_module** resource to manage kernel modules on Linux systems. This resource can load, unload, blacklist, disable, enable, install, and uninstall modules."
       introduced "14.3"
       examples <<~DOC
         Install and load a kernel module, and ensure it loads on reboot.
@@ -68,13 +68,21 @@ class Chef
         end
         ```
 
-        Disable a kernel module.
+        Disable a kernel module so that it is uninstallable.
 
         ```ruby
         kernel_module 'loop' do
           action :disable
         end
         ```
+
+        Enable a kernel module so that it is installable.  Does not load or install.
+
+        ```ruby
+        kernel_module 'loop' do
+          action :enable
+        end
+        ```
       DOC
 
       property :modname, String,
@@ -101,6 +109,9 @@ class Chef
           end
         end
 
+        # Remove the "disable file" before trying to install
+        action_enable
+
         # create options file before loading the module
         unless new_resource.options.nil?
           file "#{new_resource.unload_dir}/options_#{new_resource.modname}.conf" do
@@ -178,6 +189,20 @@ class Chef
         action_unload
       end
 
+      action :enable, description: "Enable a kernel module.  Reverse :disable actions" do
+        with_run_context :root do
+          find_resource(:execute, "update initramfs") do
+            command initramfs_command
+            action :nothing
+          end
+        end
+
+        file "#{new_resource.unload_dir}/disable_#{new_resource.modname}.conf" do
+          action :delete
+          notifies :run, "execute[update initramfs]", :delayed
+        end
+      end
+
       action :load, description: "Load a kernel module." do
         unless module_loaded?
           converge_by("load kernel module #{new_resource.modname}") do
diff --git a/spec/unit/resource/kernel_module_spec.rb b/spec/unit/resource/kernel_module_spec.rb
index aed31e03c8..b283fba0b8 100644
--- a/spec/unit/resource/kernel_module_spec.rb
+++ b/spec/unit/resource/kernel_module_spec.rb
@@ -32,10 +32,11 @@ describe Chef::Resource::KernelModule do
     expect(resource.modname).to eql("foo")
   end
 
-  it "supports :create and :flush actions" do
+  it "supports various actions" do
     expect { resource.action :install }.not_to raise_error
     expect { resource.action :uninstall }.not_to raise_error
     expect { resource.action :blacklist }.not_to raise_error
+    expect { resource.action :enable }.not_to raise_error
     expect { resource.action :disable }.not_to raise_error
     expect { resource.action :load }.not_to raise_error
     expect { resource.action :unload }.not_to raise_error