patch 'net/ixgbe: fix unexpected VLAN Rx in promisc mode on VF' has been queued to stable release 21.11.3

[Kevin Traynor]

Hi,

FYI, your patch has been queued to stable release 21.11.3

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 11/14/22. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/kevintraynor/dpdk-stable

This queued commit can be viewed at:
https://github.com/kevintraynor/dpdk-stable/commit/d95fd8e5d86a0bd94bee8afad8a4946daf758064

Thanks.

Kevin

---
>From d95fd8e5d86a0bd94bee8afad8a4946daf758064 Mon Sep 17 00:00:00 2001
From: Olivier Matz <olivier.matz at 6wind.com>
Date: Thu, 29 Sep 2022 14:09:01 +0200
Subject: [PATCH] net/ixgbe: fix unexpected VLAN Rx in promisc mode on VF
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

[ upstream commit 15ce76460a681b133709475f0eb5dbe12bb61b32 ]

When the promiscuous mode is enabled on a VF, the IXGBE_VMOLR_VPE
bit (VLAN Promiscuous Enable) is set. This means that the VF will
receive packets whose VLAN is not the same as the VLAN of the VF.

For instance, in this situation:

┌────────┐    ┌────────┐    ┌────────┐
│        │    │        │    │        │
│        │    │        │    │        │
│     VF0├────┤VF1  VF2├────┤VF3     │
│        │    │        │    │        │
└────────┘    └────────┘    └────────┘
   VM1           VM2           VM3

vf 0:  vlan 1000
vf 1:  vlan 1000
vf 2:  vlan 1001
vf 3:  vlan 1001

If we tcpdump on VF3, we see all the packets, even those transmitted
on vlan 1000.

This behavior prevents to bridge VF1 and VF2 in VM2, because it will
create a loop: packets transmitted on VF1 will be received by VF2 and
vice-versa, and bridged again through the software bridge.

This patch remove the activation of VLAN Promiscuous when a VF enables
the promiscuous mode. However, the IXGBE_VMOLR_UPE bit (Unicast
Promiscuous) is kept, so that a VF receives all packets that has the
same VLAN, whatever the destination MAC address.

A similar patch was accepted in Linux kernel (see link).
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7bb0fb7c63df

Fixes: 0355c379b71f ("net/ixgbe: support VF promiscuous by PF driver")

Signed-off-by: Olivier Matz <olivier.matz at 6wind.com>
Acked-by: Wenjun Wu <wenjun1.wu at intel.com>
---
 drivers/net/ixgbe/ixgbe_pf.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ixgbe/ixgbe_pf.c b/drivers/net/ixgbe/ixgbe_pf.c
index c5ef940533..0a0f639e39 100644
--- a/drivers/net/ixgbe/ixgbe_pf.c
+++ b/drivers/net/ixgbe/ixgbe_pf.c
@@ -772,7 +772,7 @@ ixgbe_set_vf_mc_promisc(struct rte_eth_dev *dev, uint32_t vf, uint32_t *msgbuf)
 		}
 
-		disable = 0;
+		disable = IXGBE_VMOLR_VPE;
 		enable = IXGBE_VMOLR_BAM | IXGBE_VMOLR_ROMPE |
-			 IXGBE_VMOLR_MPE | IXGBE_VMOLR_UPE | IXGBE_VMOLR_VPE;
+			 IXGBE_VMOLR_MPE | IXGBE_VMOLR_UPE;
 		break;
 	default:
-- 
2.38.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2022-11-11 10:32:17.664744660 +0000
+++ 0024-net-ixgbe-fix-unexpected-VLAN-Rx-in-promisc-mode-on-.patch	2022-11-11 10:32:17.076300776 +0000
@@ -1 +1 @@
-From 15ce76460a681b133709475f0eb5dbe12bb61b32 Mon Sep 17 00:00:00 2001
+From d95fd8e5d86a0bd94bee8afad8a4946daf758064 Mon Sep 17 00:00:00 2001
@@ -8,0 +9,2 @@
+[ upstream commit 15ce76460a681b133709475f0eb5dbe12bb61b32 ]
+
@@ -44 +45,0 @@
-Cc: stable at dpdk.org