setup-nvidia: Stop when NVIDIA sysext is loaded

Don't build NVIDIA drivers when the flatcar-nvidia-drivers sysext is
loaded, only load the prebuilt modules. Also make the nvidia.service run
after the sysexts are merged. Otherwise, it might start building the
modules and conflict with the prebuilt drivers sysext.

sdk_container/src/third_party/coreos-overlay/x11-drivers/nvidia-drivers-service/files/bin/setup-nvidia

@@ -97,20 +97,30 @@ EOF
 }
 
 function install_and_load() {
-  # This creates symlinks to sonames
-  mkdir -p /etc/ld.so.conf.d/
-  echo "/opt/nvidia/${NVIDIA_CURRENT_INSTALLATION}/usr/lib64" > /etc/ld.so.conf.d/nvidia.conf
-  ldconfig
-
   modprobe -a i2c_core ipmi_msghandler ipmi_devintf
   # This is needed on amd64 due to CONFIG_ACPI_VIDEO=m
   modprobe -q video || true
 
-  pushd "/opt/nvidia/${NVIDIA_CURRENT_INSTALLATION}/usr/lib/modules/$(uname -r)/video/"
-  insmod nvidia.ko
-  insmod nvidia-modeset.ko
-  insmod nvidia-uvm.ko
-  popd
+  if systemd-sysext list | grep -q flatcar-nvidia-drivers; then
+    modprobe nvidia
+    modprobe nvidia-modeset
+    modprobe nvidia-uvm
+
+    systemctl daemon-reload
+    # create the nvpd user
+    systemd-sysusers
+  else
+    # This creates symlinks to sonames
+    mkdir -p /etc/ld.so.conf.d/
+    echo "/opt/nvidia/${NVIDIA_CURRENT_INSTALLATION}/usr/lib64" > /etc/ld.so.conf.d/nvidia.conf
+
+    pushd "/opt/nvidia/${NVIDIA_CURRENT_INSTALLATION}/usr/lib/modules/$(uname -r)/video/"
+    insmod nvidia.ko
+    insmod nvidia-modeset.ko
+    insmod nvidia-uvm.ko
+    popd
+  fi
+  ldconfig
 
   # based on https://docs.nvidia.com/cuda/cuda-installation-guide-linux/index.html#runfile-verifications
   if [ ! -c /dev/nvidiactl ]
@@ -161,6 +171,11 @@ function is_nvidia_installation_required() {
   if [[ -d "/opt/nvidia/${NVIDIA_FLATCAR_VERSION_PAIR}" ]]; then
     return 1
   fi
+
+  if systemd-sysext list | grep -q flatcar-nvidia-drivers; then
+    echo "Pre-build NVIDIA drivers sysext is loaded, skipping drivers build."
+    return 1
+  fi
 }
 
 function presetup() {

sdk_container/src/third_party/coreos-overlay/x11-drivers/nvidia-drivers-service/files/units/nvidia.service

@@ -1,7 +1,7 @@
 [Unit]
 Description=NVIDIA Configure Service
 Wants=network-online.target
-After=network-online.target
+After=network-online.target systemd-sysext.service
 Before=containerd.target
 
 [Service]