• Olivier Matz's avatar
    ixgbe: fix unexpected VLAN Rx in promisc mode on VF · 7bb0fb7c
    Olivier Matz authored
    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.
    
    Fixes: 8443c1a4 ("ixgbe, ixgbevf: Add new mbox API xcast mode")
    Cc: stable@vger.kernel.org
    Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
    Signed-off-by: default avatarOlivier Matz <olivier.matz@6wind.com>
    Tested-by: default avatarKonrad Jankowski <konrad0.jankowski@intel.com>
    Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
    7bb0fb7c
ixgbe_sriov.c 48.1 KB