diff --git a/sys/oom_linux.go b/sys/oom_linux.go
index 6e759a0b1..82a347c6f 100644
--- a/sys/oom_linux.go
+++ b/sys/oom_linux.go
@@ -65,7 +65,8 @@ func SetOOMScore(pid, score int) error {
 	return nil
 }
 
-// GetOOMScoreAdj gets the oom score for a process
+// GetOOMScoreAdj gets the oom score for a process. It returns 0 (zero) if either
+// no oom score is set, or a sore is set to 0.
 func GetOOMScoreAdj(pid int) (int, error) {
 	path := fmt.Sprintf("/proc/%d/oom_score_adj", pid)
 	data, err := ioutil.ReadFile(path)
diff --git a/sys/oom_linux_test.go b/sys/oom_linux_test.go
index bcbb1bc04..3cea56a75 100644
--- a/sys/oom_linux_test.go
+++ b/sys/oom_linux_test.go
@@ -71,9 +71,11 @@ func TestSetOOMScoreBoundaries(t *testing.T) {
 
 	score, err := GetOOMScoreAdj(os.Getpid())
 	assert.NilError(t, err)
-	if score == 0 || score == OOMScoreAdjMin {
-		// we won't be able to set the score lower than the parent process,
-		// so only test if parent process does not have a oom-score-adj
+	if score == OOMScoreAdjMin {
+		// We won't be able to set the score lower than the parent process. This
+		// could also be tested if the parent process does not have a oom-score-adj
+		// set, but GetOOMScoreAdj does not distinguish between "not set" and
+		// "score is set, but zero".
 		_, adjustment, err = adjustOom(OOMScoreAdjMin)
 		assert.NilError(t, err)
 		assert.Check(t, is.Equal(adjustment, OOMScoreAdjMin))