diff --git a/.github/workflows/build-stable.yaml b/.github/workflows/build-stable.yaml
index 6ad9081..73b5381 100644
--- a/.github/workflows/build-stable.yaml
+++ b/.github/workflows/build-stable.yaml
@@ -8,8 +8,13 @@ on:
         required: true
         default: '5.4.0-1058-raspi'
         type: string
+      lttng_version:
+        description: 'LTTNG version e.g. 2.12'
+        required: false
+        type: string
 jobs:
   call-rpi4-kernel-build:
     uses: ./.github/workflows/rpi4-kernel-build.yml
     with:
       uname_r: ${{ github.event.inputs.uname_r }}
+      lttng_version: ${{ github.event.inputs.lttng_version }}
diff --git a/Dockerfile b/Dockerfile
index 459a28f..4371f4f 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -116,9 +116,8 @@ RUN cd /home/user/linux_build \
     && gunzip patch-`cat /home/user/rt_patch`.patch.gz
 
 # download lttng source for use later
-# TODO(flynneva): make script to auto-determine which version to get?
 RUN cd /home/user/ \
-    && sudo apt-add-repository ppa:lttng/stable-${LTTNG_VERSION} \
+    && sudo apt-add-repository -s -y ppa:lttng/stable-${LTTNG_VERSION} \
     && sudo apt-get update \
     && apt-get source lttng-modules-dkms