From b8e9e7d82e7eefd5d2d528469d94ec20e96b38c3 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Sat, 12 Sep 2026 13:31:01 -0700 Subject: [PATCH] selftests: drv-net: devmem: set reuseaddr on the sender's source port devmem.py fails on the HW runners with: CMD[remote]: dd if=/dev/zero bs=512 count=1 2>/dev/null | socat -b 512 \ -u - TCP6:[fd00:2::1]:50051,bind=[fd00:2::2]:50051,nodelay STDERR: socat[41018] W bind(5, {AF=10 [fd00:2::2]:50051}, 28): \ Address already in use ncdevmem installs a 5-tuple flow rule which matches the source port, so socat has to bind it explicitly. The port comes from rand_port(), which checks availability on the DUT - but we bind on the remote... That said the failure rate seems to high to be random collisions (~2% per sub-test). It's probably TIME_WAIT sockets on the remote, run_rx_hds() alone creates 12 of them. Set reuseaddr so a TIME_WAIT socket does not fail the bind. Collisions with a live socket are still possible, we'll see if they are frequent enough to care. Reviewed-by: Breno Leitao Reviewed-by: Bobby Eshleman Signed-off-by: Jakub Kicinski Link: https://patch.msgid.link/20260912203101.153688-1-kuba@kernel.org Signed-off-by: Paolo Abeni --- tools/testing/selftests/drivers/net/hw/devmem_lib.py | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/drivers/net/hw/devmem_lib.py b/tools/testing/selftests/drivers/net/hw/devmem_lib.py index 3554954a6691..71b916c16196 100644 --- a/tools/testing/selftests/drivers/net/hw/devmem_lib.py +++ b/tools/testing/selftests/drivers/net/hw/devmem_lib.py @@ -201,7 +201,7 @@ def socat_send(cfg, port, buf_size=0): else: addr = cfg.baddr - suffix = f",bind={cfg.remote_baddr}:{port}" + suffix = f",bind={cfg.remote_baddr}:{port},reuseaddr" buf = "" if buf_size: @@ -213,7 +213,7 @@ def socat_send(cfg, port, buf_size=0): def socat_listen(cfg, port): """Socat listen command for TX tests.""" - return f"socat -U - TCP{cfg.addr_ipver}-LISTEN:{port}" + return f"socat -U - TCP{cfg.addr_ipver}-LISTEN:{port},reuseaddr" def setup_test(cfg, bin_local):