1. 15 Nov, 2022 1 commit
    • Amit Cohen's avatar
      mlxsw: Avoid warnings when not offloaded FDB entry with IPv6 is removed · 30f5312d
      Amit Cohen authored
      FDB entries that perform VXLAN encapsulation with an IPv6 underlay hold
      a reference on a resource - the KVDL entry where the IPv6 underlay
      destination IP is stored. For that, the driver maintains two hash tables:
      1. Maps IPv6 to KVDL index
      2. Maps {MAC, FID index} to IPv6 address
      
      When a FDB entry is removed, the second table is used to find the relevant
      IPv6 address and the first table is used to remove the reference count and
      free the index if is not used anymore.
      
      In order for a packet to be forwarded to a single remote VTEP, FDB
      entries need to be configured at both the bridge and VXLAN devices' FDB
      tables. Both entries are squashed into one {MAC, VLAN/VNI} -> IP entry
      in the hardware. Therefore, in case one entry is removed, the entry will
      be removed from the hardware and the remaining entry will be unmarked
      with 'offload' flag since it is not offloaded anymore.
      
      For example, the two FDB entries should be added to allow packets to be
      forwarded via vx10:
      $ bridge fdb add dev vx10 aa:bb:cc:dd:ee:ff self static dst 2001:db8:5::1
      $ bridge fdb add dev vx10 aa:bb:cc:dd:ee:ff master static vlan 10
      
      When one entry will be removed, the second one will not be offloaded
      anymore. When the first entry (in VXLAN FDB) will be removed / will not be
      offloaded anymore, the two mappings in IPv6 hash tables will be removed.
      
      In case that the second entry is removed before the first one, unexpected
      warnings[1][2] will be shown in user space as a result of removing the
      first entry. The issue is that not offloaded entry is removed, the driver
      tries to search the relevant entries in the hash tables, does not find them
      and therefore warns.
      
      Do not handle removing of not offloaded VXLAN FDB entries, as they were
      already removed when the offload flag was removed.
      
      [1]:
      WARNING: CPU: 1 PID: 239 at drivers/net/ethernet/mellanox/mlxsw/spectrum_nve.c:914 mlxsw_sp_nve_ipv6_addr_map_del+0x6b/0x80 [mlxsw_spectrum]
      ...
      Hardware name: Mellanox Technologies Ltd. Mellanox switch/Mellanox switch, BIOS 4.6.5 05/21/2015
      Workqueue: mlxsw_core_ordered mlxsw_sp_switchdev_vxlan_fdb_event_work [mlxsw_spectrum]
      RIP: 0010:mlxsw_sp_nve_ipv6_addr_map_del+0x6b/0x80 [mlxsw_spectrum]
      ...
      Call Trace:
        <TASK>
        mlxsw_sp_port_fdb_tunnel_uc_op+0x6cf/0x7b0 [mlxsw_spectrum]
        mlxsw_sp_switchdev_vxlan_fdb_event_work+0x17c/0x420 [mlxsw_spectrum]
        ? finish_task_switch.isra.0+0x8c/0x290
        process_one_work+0x1cd/0x390
        worker_thread+0x48/0x3c0
        ? process_one_work+0x390/0x390
        kthread+0xe0/0x110
        ? kthread_complete_and_exit+0x20/0x20
        ret_from_fork+0x1f/0x30
        </TASK>
      
      [2]:
      WARNING: CPU: 0 PID: 239 at drivers/net/ethernet/mellanox/mlxsw/spectrum.c:3035 mlxsw_sp_ipv6_addr_put+0x142/0x220 [mlxsw_spectrum]
      ...
      Hardware name: Mellanox Technologies Ltd. Mellanox switch/Mellanox switch, BIOS 4.6.5 05/21/2015
      Workqueue: mlxsw_core_ordered mlxsw_sp_switchdev_vxlan_fdb_event_work [mlxsw_spectrum]
      RIP: 0010:mlxsw_sp_ipv6_addr_put+0x142/0x220 [mlxsw_spectrum]
      ...
      Call Trace:
        <TASK>
        ? mlxsw_sp_port_fdb_tun_uc_op6_sfd_write+0x5c1/0x610 [mlxsw_spectrum]
        mlxsw_sp_port_fdb_tunnel_uc_op+0x6ec/0x7b0 [mlxsw_spectrum]
        mlxsw_sp_switchdev_vxlan_fdb_event_work+0x17c/0x420 [mlxsw_spectrum]
        ? finish_task_switch.isra.0+0x8c/0x290
        process_one_work+0x1cd/0x390
        worker_thread+0x48/0x3c0
        ? process_one_work+0x390/0x390
        kthread+0xe0/0x110
        ? kthread_complete_and_exit+0x20/0x20
        ret_from_fork+0x1f/0x30
        </TASK>
      
      Fixes: 0860c764 ("mlxsw: spectrum_nve: Keep track of IPv6 addresses used by FDB entries")
      Signed-off-by: default avatarAmit Cohen <amcohen@nvidia.com>
      Reviewed-by: default avatarIdo Schimmel <idosch@nvidia.com>
      Signed-off-by: default avatarPetr Machata <petrm@nvidia.com>
      Link: https://lore.kernel.org/r/c186de8cbd28e3eb661e06f31f7f2f2dff30020f.1668184350.git.petrm@nvidia.comSigned-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      30f5312d
  2. 14 Nov, 2022 12 commits
  3. 12 Nov, 2022 8 commits
  4. 11 Nov, 2022 10 commits
  5. 10 Nov, 2022 9 commits