Add install-zfs-dkms-module example

- [x] Add install-zfs-dkms-module example Containerfile and readme
- [x] Add install-zfs-dkms-module example to main readme
- [x] Add install-zfs-dkms-module github workflow file
- [x] Test build install-zfs-dkms-module example

.github/workflows/install-zfs-dkms-module.yml

@@ -0,0 +1,34 @@
+name: "Build image: install-zfs-dkms-module"
+
+env:
+  IMAGE_NAME: "install-zfs-dkms-module"
+
+on:
+  pull_request:
+    branches:
+      - main
+    paths:
+      - install-zfs-dkms-module/*
+      - .github/workflows/install-zfs-dkms-module.yml
+  push:
+    branches:
+      - main
+    paths:
+      - install-zfs-dkms-module/*
+      - .github/workflows/install-zfs-dkms-module.yml
+
+jobs:
+  build-image:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repo
+        uses: actions/checkout@v3
+
+      - name: Build container image
+        uses: redhat-actions/buildah-build@v2
+        with:
+          context: ${{ env.IMAGE_NAME }}
+          containerfiles: ${{ env.IMAGE_NAME }}/Containerfile
+          image: ${{ env.IMAGE_NAME }}
+          layers: false
+          oci: true

README.md

@@ -20,6 +20,7 @@ functionality.
 - [butane](butane/): Demos using https://github.com/coreos/butane
 - [initramfs-module](initramfs-module/): Demos generating a initramfs with specific modules added and omitted.
 - [inject-go-binary](inject-go-binary/): Demos adding building and injecting a Go binary + systemd unit
+- [install-zfs-dkms-module](install-zfs-dkms-module/): Install ZFS DKMS Kernel Module
 - [podman-next](podman-next): Use COPR to install the podman-next package
 - [rsyslog](rsyslog/): Install and configure rsyslog to forward to a remote host
 - [replace-kernel](replace-kernel): Replace the kernel using packages from Koji

install-zfs-dkms-module/Containerfile

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+# Install ZFS DKMS Kernel Module
+FROM quay.io/fedora/fedora-coreos:stable
+
+# Install ZFS repository
+RUN rpm-ostree install \
+    https://zfsonlinux.org/fedora/zfs-release-2-3$(rpm --eval "%{dist}").noarch.rpm && \
+    ostree container commit
+
+# Install dkms dependencies
+RUN rpm-ostree install kernel-devel kernel-devel-matched kernel-headers kernel-srpm-macros && \
+    ostree container commit
+
+# TODO: Remove the following line once these bugs are fixed:
+# - https://github.com/coreos/rpm-ostree/issues/4201
+# - https://github.com/coreos/rpm-ostree/issues/1614
+RUN test -f /usr/bin/ld || ln -s /usr/bin/ld.bfd /usr/bin/ld
+
+# Install zfs package and tell dkms to install the kernel module now
+RUN rpm-ostree install zfs && \
+    dkms autoinstall -k $(rpm -qa kernel --queryformat '%{VERSION}-%{RELEASE}.%{ARCH}') && \
+    rm -vrf /var && \
+    test -h /usr/bin/ld && rm -v /usr/bin/ld && \
+    ostree container commit

install-zfs-dkms-module/README.md

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+# Install ZFS DKMS Kernel Module
+
+This example installs the [ZFS](https://openzfs.org/) [DKMS](https://en.wikipedia.org/wiki/Dynamic_Kernel_Module_Support) kernel module.
+
+This is useful because typically DKMS modules are built during system startup after a kernel has been updated. This doesn't work in `ostree` based distributions because DKMS attempts to install kernel modules into `/usr`, which on `ostree` based distributions is mounted read-only.
+
+This example is not specific to ZFS and should be able to be applied to other DKMS modules.