Re: [PATCH net] selftests: forwarding: vxlan_bridge_1d: Fix vxlan ecn decapsulate value
From: Hangbin Liu <hidden>
Date: 2021-03-22 01:17:20
On Sun, Mar 21, 2021 at 07:20:55PM +0200, Ido Schimmel wrote:
On Fri, Mar 19, 2021 at 10:33:14PM +0800, Hangbin Liu wrote:quoted
The ECN bit defines ECT(1) = 1, ECT(0) = 2. So inner 0x02 + outer 0x01 should be inner ECT(0) + outer ECT(1). Based on the description of __INET_ECN_decapsulate, the final decapsulate value should be ECT(1). So fix the test expect value to 0x01. Before the fix: TEST: VXLAN: ECN decap: 01/02->0x02 [FAIL] Expected to capture 10 packets, got 0. After the fix: TEST: VXLAN: ECN decap: 01/02->0x01 [ OK ] Fixes: a0b61f3d8ebf ("selftests: forwarding: vxlan_bridge_1d: Add an ECN decap test") Signed-off-by: Hangbin Liu <redacted>Fixes: b723748750ec ("tunnel: Propagate ECT(1) when decapsulating as recommended by RFC6040") The commit you cited is from 2018 whereas this one is from 2020. The test stopped working after the latter. The reason I didn't see it is because this commit only changed one caller of __INET_ECN_decapsulate(). Another caller is mlxsw which uses the function to understand how to program the hardware to perform decapsulation. See commit 28e450333d4d ("inet: Refactor INET_ECN_decapsulate()").
Hi Ido, Thanks for this info. I don't have mlxsw card in hand, so I never run the driver test before. Cheers Hangbin
quoted hunk ↗ jump to hunk
After your patch I get: TEST: VXLAN: ECN decap: 01/02->0x01 [FAIL] Expected to capture 10 packets, got 0. Fixed by:diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c index b8b08a6a1d10..61eb34e20fde 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c@@ -341,7 +341,12 @@ static int mlxsw_sp_ipip_ecn_decap_init_one(struct mlxsw_sp *mlxsw_sp, u8 new_inner_ecn; trap_en = __INET_ECN_decapsulate(outer_ecn, inner_ecn, &set_ce); - new_inner_ecn = set_ce ? INET_ECN_CE : inner_ecn; + if (set_ce) + new_inner_ecn = INET_ECN_CE; + else if (outer_ecn == INET_ECN_ECT_1) + new_inner_ecn = INET_ECN_ECT_1; + else + new_inner_ecn = inner_ecn; mlxsw_reg_tidem_pack(tidem_pl, outer_ecn, inner_ecn, new_inner_ecn, trap_en, trap_en ? MLXSW_TRAP_ID_DECAP_ECN0 : 0);diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_nve.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_nve.c index e5ec595593f4..74f2c4ce7063 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_nve.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_nve.c@@ -913,7 +913,12 @@ static int __mlxsw_sp_nve_ecn_decap_init(struct mlxsw_sp *mlxsw_sp, u8 new_inner_ecn; trap_en = !!__INET_ECN_decapsulate(outer_ecn, inner_ecn, &set_ce); - new_inner_ecn = set_ce ? INET_ECN_CE : inner_ecn; + if (set_ce) + new_inner_ecn = INET_ECN_CE; + else if (outer_ecn == INET_ECN_ECT_1) + new_inner_ecn = INET_ECN_ECT_1; + else + new_inner_ecn = inner_ecn; mlxsw_reg_tndem_pack(tndem_pl, outer_ecn, inner_ecn, new_inner_ecn, trap_en, trap_en ? MLXSW_TRAP_ID_DECAP_ECN0 : 0);I will prepare a patch