install: inject kernel arguments for seperate /boot during installation

Signed-off-by: Huijing Hei <[email protected]>

Author: HuijingHei

crates/lib/src/install.rs

@@ -970,6 +970,23 @@ async fn install_container(
         }
     }
 
+    // For seperate /boot filesystem, the better workaround is
+    // to inject kernel arguments during installation.
+    // See discussion in https://github.com/bootc-dev/bootc/issues/1388
+    if let Some(boot) = root_setup.boot.as_ref() {
+        if !boot.source.is_empty() {
+            let mount_extra = format!(
+                "systemd.mount-extra={}:{}:{}:{}",
+                boot.source,
+                boot.target,
+                boot.fstype,
+                boot.options.as_deref().unwrap_or("defaults")
+            );
+            kargs.extend(&Cmdline::from(mount_extra.as_str()));
+            tracing::debug!("Add {mount_extra} to kargs");
+        }
+    }
+
     // Finally map into &[&str] for ostree_container
     let kargs_strs: Vec<&str> = kargs.iter_str().collect();