fips: ensure fs module for /boot is installed

When using dracut with  --hostonly and --no-hostonly-default-device,
/boot will be inaccessible as dracut will most fs modules unless
specified. But FIPS require /boot to be accessible, and it will try
to mount it on boot. It will fail if corresponding fs module is missing.

For most case /boot will be a simple partition, include the fs module
will be enough for FIPS to mount it. For other cases users have to pass
extra parameters by themselves.

Suggested-by: Kenneth Dsouza <kdsouza@redhat.com>
Signed-off-by: Kairui Song <kasong@redhat.com>

modules.d/01fips/module-setup.sh

@@ -12,7 +12,7 @@ depends() {
 
 # called by dracut
 installkernel() {
-    local _fipsmodules _mod
+    local _fipsmodules _mod _bootfstype
     if [[ -f "${srcmods}/modules.fips" ]]; then
         _fipsmodules="$(cat "${srcmods}/modules.fips")"
     else
@@ -47,6 +47,16 @@ installkernel() {
             echo "blacklist $_mod" >> "${initdir}/etc/modprobe.d/fips.conf"
         fi
     done
+
+    # with hostonly_default_device fs module for /boot is not installed by default
+    if [[ $hostonly ]] && [[ "$hostonly_default_device" == "no" ]]; then
+        _bootfstype=$(find_mp_fstype /boot)
+        if [[ -n "$_bootfstype" ]]; then
+            hostonly='' instmods $_bootfstype
+        else
+            dwarning "Can't determine fs type for /boot, FIPS check may fail."
+        fi
+    fi
 }
 
 # called by dracut