cmd/earlyinit: improve error messages

This improves readability, especially on a small display.

Signed-off-by: Ophestra <cat@gensokyo.uk>

cmd/earlyinit/main.go

@@ -7,6 +7,7 @@ package main
 import (
 	"context"
 	"crypto/rand"
+	"io"
 	"log"
 	"os"
 	"os/signal"
@@ -51,13 +52,14 @@ func init() {
 func fatal(v ...any) {
 	log.Println(v...)
 	log.Println("unable to continue, please reboot and resolve the problem manually")
+	log.SetOutput(io.Discard)
 	select {}
 }
 
 // must calls fatal with err if it is non-nil.
 func must(err error) {
 	if err != nil {
-		log.Println(err)
+		fatal(err)
 		select {}
 	}
 }

cmd/earlyinit/modprobe.go

@@ -26,8 +26,9 @@ var _ report.RepresentableError = ModprobeError{}
 func (ModprobeError) Representable() {}
 func (e ModprobeError) Error() string {
 	return fmt.Sprintf(
-		"modprobe exit status %d: %s",
+		"%s (exit status %d)",
-		e.ExitCode, strings.TrimSpace(e.Stderr),
+		strings.TrimPrefix(strings.TrimSpace(e.Stderr), "modprobe: "),
+		e.ExitCode,
 	)
 }