diff --git a/tests/hwsim/hwsim_utils.py b/tests/hwsim/hwsim_utils.py
index 48eee0f8b..7b0afb496 100644
--- a/tests/hwsim/hwsim_utils.py
+++ b/tests/hwsim/hwsim_utils.py
@@ -11,7 +11,7 @@ logger = logging.getLogger()
 
 from wpasupplicant import WpaSupplicant
 
-def _sync_carrier(dev, ifname):
+def sync_carrier(dev, ifname=None):
     ifname = ifname or dev.ifname
     carrier_p2p = None
     try:
@@ -40,7 +40,7 @@ def config_data_test(dev1, dev2, dev1group, dev2group, ifname1, ifname2):
     if "OK" not in res:
         raise Exception("Failed to enable data test functionality")
 
-    _sync_carrier(dev1, ifname1)
+    sync_carrier(dev1, ifname1)
 
     cmd = "DATA_TEST_CONFIG 1"
     if ifname2:
@@ -52,7 +52,7 @@ def config_data_test(dev1, dev2, dev1group, dev2group, ifname1, ifname2):
     if "OK" not in res:
         raise Exception("Failed to enable data test functionality")
 
-    _sync_carrier(dev2, ifname2)
+    sync_carrier(dev2, ifname2)
 
 def run_multicast_connectivity_test(dev1, dev2, tos=None,
                                     dev1group=False, dev2group=False,
diff --git a/tests/hwsim/test_ap_hs20.py b/tests/hwsim/test_ap_hs20.py
index afb54c5d5..81becf04f 100644
--- a/tests/hwsim/test_ap_hs20.py
+++ b/tests/hwsim/test_ap_hs20.py
@@ -5483,6 +5483,7 @@ def run_proxyarp_errors(dev, apdev, params):
         pkt = build_ns(src_ll=addr0, ip_src="aaaa:bbbb:cccc::2",
                        ip_dst="ff02::1:ff00:2", target="aaaa:bbbb:cccc::2",
                        opt=src_ll_opt0)
+        hwsim_utils.sync_carrier(dev[0])
         if "OK" not in dev[0].request("DATA_TEST_FRAME " + binascii.hexlify(pkt).decode()):
             raise Exception("DATA_TEST_FRAME failed")
         wait_fail_trigger(hapd, "GET_ALLOC_FAIL")