Make every failed check and unreadable counter fatal instead of degrading

system.go

@@ -462,6 +462,7 @@ func checkGovernor(want string) checkResult {
 	paths, err := filepath.Glob("/sys/devices/system/cpu/cpu*/cpufreq/scaling_governor")
 	if err != nil || len(paths) == 0 {
 		res.err = fmt.Errorf("no cpufreq governors found")
+		res.fatal = true
 		return res
 	}
 	var wrong []string
@@ -470,6 +471,7 @@ func checkGovernor(want string) checkResult {
 		b, err := os.ReadFile(p)
 		if err != nil {
 			res.err = err
+			res.fatal = true
 			return res
 		}
 		got := strings.TrimSpace(string(b))
@@ -490,6 +492,7 @@ func checkGovernor(want string) checkResult {
 		if err := os.WriteFile(p, []byte(want), 0o644); err != nil {
 			res.err = err
 			res.state = fmt.Sprintf("could not set %s", p)
+			res.fatal = true
 			return res
 		}
 	}
@@ -532,6 +535,7 @@ func checkCoalesce(fd int, ifname string, rxUsecs, txUsecs uint32) checkResult {
 	ec, err := getCoalesce(fd, ifname)
 	if err != nil {
 		res.err = err
+		res.fatal = true
 		return res
 	}
 	desc := func(e ethtoolCoalesce) string {
@@ -552,6 +556,7 @@ func checkCoalesce(fd int, ifname string, rxUsecs, txUsecs uint32) checkResult {
 	if err := ethtoolCall(fd, ifname, unsafe.Pointer(&ec)); err != nil {
 		res.err = err
 		res.state = "could not set"
+		res.fatal = true
 		return res
 	}
 	res.fixed = true
@@ -564,6 +569,7 @@ func checkRings(fd int, ifname string, rxWant, txWant uint32) checkResult {
 	rp, err := getRings(fd, ifname)
 	if err != nil {
 		res.err = err
+		res.fatal = true
 		return res
 	}
 	rx := min(rxWant, rp.rxMaxPending)
@@ -579,6 +585,7 @@ func checkRings(fd int, ifname string, rxWant, txWant uint32) checkResult {
 	if err := ethtoolCall(fd, ifname, unsafe.Pointer(&rp)); err != nil {
 		res.err = err
 		res.state = "could not set"
+		res.fatal = true
 		return res
 	}
 	res.fixed = true