Subject: [PATCH net-next 3/6] selftests: drv-net: gro: always wait for FIN in the capacity test

From: Jakub Kicinski <[email-masked]>
Date: Wed, 1 Apr 2026 11:26:22 -0700

The new capacity/order test exits as soon as it sees the expected
packet sequence. This may allow the "flushing" FIN packet to spill
over to the next test. Let's always wait for the FIN before exiting.

Signed-off-by: Jakub Kicinski <[email-masked]>
---
 tools/testing/selftests/net/lib/gro.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/net/lib/gro.c b/tools/testing/selftests/net/lib/gro.c
index 27ccd742615a..f05398c18e0c 100644
--- a/tools/testing/selftests/net/lib/gro.c
+++ b/tools/testing/selftests/net/lib/gro.c
@@ -1154,7 +1154,7 @@ static void check_capacity_pkts(int fd)
 	memset(coalesced, 0, sizeof(coalesced));
 	memset(flow_order, -1, sizeof(flow_order));
 
-	while (total_data < num_flows * CAPACITY_PAYLOAD_LEN * 2) {
+	while (1) {
 		ip_ext_len = 0;
 		pkt_size = recv(fd, buffer, IP_MAXPACKET + ETH_HLEN + 1, 0);
 		if (pkt_size < 0)
@@ -1167,7 +1167,6 @@ static void check_capacity_pkts(int fd)
 
 		tcph = (struct tcphdr *)(buffer + tcp_offset + ip_ext_len);
 
-		/* FIN packet terminates reception */
 		if (tcph->fin)
 			break;
 
@@ -1189,7 +1188,13 @@ static void check_capacity_pkts(int fd)
 			data_len = pkt_size - total_hdr_len - ip_ext_len;
 		}
 
-		flow_order[num_pkt] = flow_id;
+		if (num_pkt < num_flows * 2) {
+			flow_order[num_pkt] = flow_id;
+		} else if (num_pkt == num_flows * 2) {
+			vlog("More packets than expected (%d)\n",
+			     num_flows * 2);
+			fail_reason = fail_reason ?: "too many packets";
+		}
 		coalesced[flow_id] = data_len;
 
 		if (data_len == CAPACITY_PAYLOAD_LEN * 2) {
-- 
2.53.0