6.17-stable review patch. If anyone has any objections, please let me know.
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From: Anubhav Singh anubhavsinggh@google.com
[ Upstream commit 02d064de05b1fcca769391fa82d205bed8bb9bf0 ]
Due to the gro_sender sending data packets and FIN packets in very quick succession, these are received almost simultaneously by the gro_receiver. FIN packets are sometimes processed before the data packets leading to intermittent (~1/100) test failures.
This change adds a delay of 100ms before sending FIN packets in gro:tcp test to avoid the out-of-order delivery. The same mitigation already exists for the gro:ip test.
Fixes: 7d1575014a63 ("selftests/net: GRO coalesce test") Reviewed-by: Willem de Bruijn willemb@google.com Signed-off-by: Anubhav Singh anubhavsinggh@google.com Link: https://patch.msgid.link/20251030062818.1562228-1-anubhavsinggh@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- tools/testing/selftests/net/gro.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/tools/testing/selftests/net/gro.c b/tools/testing/selftests/net/gro.c index d5824eadea109..209ec60052f5b 100644 --- a/tools/testing/selftests/net/gro.c +++ b/tools/testing/selftests/net/gro.c @@ -969,6 +969,7 @@ static void check_recv_pkts(int fd, int *correct_payload,
static void gro_sender(void) { + const int fin_delay_us = 100 * 1000; static char fin_pkt[MAX_HDR_LEN]; struct sockaddr_ll daddr = {}; int txfd = -1; @@ -1012,15 +1013,22 @@ static void gro_sender(void) write_packet(txfd, fin_pkt, total_hdr_len, &daddr); } else if (strcmp(testname, "tcp") == 0) { send_changed_checksum(txfd, &daddr); + /* Adding sleep before sending FIN so that it is not + * received prior to other packets. + */ + usleep(fin_delay_us); write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
send_changed_seq(txfd, &daddr); + usleep(fin_delay_us); write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
send_changed_ts(txfd, &daddr); + usleep(fin_delay_us); write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
send_diff_opt(txfd, &daddr); + usleep(fin_delay_us); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); } else if (strcmp(testname, "ip") == 0) { send_changed_ECN(txfd, &daddr);