FAILED: patch "[PATCH] ixgbe: fix unexpected VLAN Rx in promisc mode on VF" failed to apply to 4.9-stable tree

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 7bb0fb7c63df95d6027dc50d6af3bc3bbbc25483 Mon Sep 17 00:00:00 2001
From: Olivier Matz <[email protected]>
Date: Wed, 6 Apr 2022 11:52:52 +0200
Subject: [PATCH] ixgbe: fix unexpected VLAN Rx in promisc mode on VF
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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 than 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.

index 8d108a78941b..d4e63f0644c3 100644
@@ -1208,9 +1208,9 @@ static int ixgbe_update_vf_xcast_mode(struct ixgbe_adapter *adapter,
 			return -EPERM;
 		}
 
-		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:
 		return -EOPNOTSUPP;