diff --git a/tests/hwsim/test_ap_vht.py b/tests/hwsim/test_ap_vht.py
index 8ffa81895..2b691ff71 100644
--- a/tests/hwsim/test_ap_vht.py
+++ b/tests/hwsim/test_ap_vht.py
@@ -553,7 +553,7 @@ def run_ap_vht160_no_dfs(dev, apdev, channel, ht_capab):
             cmd = subprocess.Popen(["iw", "reg", "get"], stdout=subprocess.PIPE)
             reg = cmd.stdout.readlines()
             for r in reg:
-                if "5490" in r and "DFS" in r:
+                if b"5490" in r and b"DFS" in r:
                     raise HwsimSkip("ZA regulatory rule did not have DFS requirement removed")
             raise Exception("AP setup timed out")
 
diff --git a/tests/hwsim/test_he.py b/tests/hwsim/test_he.py
index f033285a6..28123e853 100644
--- a/tests/hwsim/test_he.py
+++ b/tests/hwsim/test_he.py
@@ -623,7 +623,7 @@ def run_ap_he160_no_dfs(dev, apdev, channel, ht_capab):
             cmd = subprocess.Popen(["iw", "reg", "get"], stdout=subprocess.PIPE)
             reg = cmd.stdout.readlines()
             for r in reg:
-                if "5490" in r and "DFS" in r:
+                if b"5490" in r and b"DFS" in r:
                     raise HwsimSkip("ZA regulatory rule did not have DFS requirement removed")
             raise Exception("AP setup timed out")