| Message ID | 20210518210849.1673577-3-jarod@redhat.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [1/4] bonding: add pure source-mac-based tx hashing option | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | warning | Series does not have a cover letter |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Guessed tree name to be net-next |
| netdev/subject_prefix | warning | Target tree name not specified in the subject |
| netdev/cc_maintainers | success | CCed 6 of 6 maintainers |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | fail | Errors and warnings before: 0 this patch: 2 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 35 lines checked |
| netdev/build_allmodconfig_warn | fail | Errors and warnings before: 0 this patch: 2 |
| netdev/header_inline | success | Link |
Jarod Wilson <jarod@redhat.com> wrote: >With a virtual machine behind a bridge on top of a bond, outgoing traffic >should retain the VM's source MAC. That works fine most of the time, until >doing a failover, and then the MAC gets rewritten to the bond slave's MAC, >and the return traffic gets dropped. If we don't rewrite the MAC there, we >don't lose any traffic. Please have the log message here specify that this applies only to balance-alb mode, and, the usual nomenclature for bonding patches is "[PATCH] bonding:"; for this case, I'd suggest "balance-alb:" right afterwards to be clear that it's only for alb mode. I didn't really spot the "bond_alb" tag for what it was on first read, and it is the only indication that this change is specific to alb mode other than the patch itself. >Cc: Jay Vosburgh <j.vosburgh@gmail.com> >Cc: Veaceslav Falico <vfalico@gmail.com> >Cc: Andy Gospodarek <andy@greyhouse.net> >Cc: "David S. Miller" <davem@davemloft.net> >Cc: Jakub Kicinski <kuba@kernel.org> >Cc: Thomas Davis <tadavis@lbl.gov> >Cc: netdev@vger.kernel.org >Signed-off-by: Jarod Wilson <jarod@redhat.com> >--- > drivers/net/bonding/bond_alb.c | 23 ++++++++++++++++++++++- > 1 file changed, 22 insertions(+), 1 deletion(-) > >diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c >index 3455f2cc13f2..ce8257c7cbea 100644 >--- a/drivers/net/bonding/bond_alb.c >+++ b/drivers/net/bonding/bond_alb.c >@@ -1302,6 +1302,26 @@ void bond_alb_deinitialize(struct bonding *bond) > rlb_deinitialize(bond); > } > >+static bool bond_alb_bridged_mac(struct bonding *bond, struct ethhdr *eth_data) >+{ >+ struct list_head *iter; >+ struct slave *slave; >+ >+ if (BOND_MODE(bond) != BOND_MODE_ALB) >+ return false; >+ >+ /* Don't modify source MACs that do not originate locally >+ * (e.g.,arrive via a bridge). >+ */ >+ if (!netif_is_bridge_port(bond->dev)) >+ return false; I believe this logic will fail if the plumbing is, e.g., bond -> vlan -> bridge, as netif_is_bridge_port() would not return true for the bond in that case. Making this reliable is tricky at best, and may be impossible to be correct for all possible cases. As such, I think the comment above should reflect the limited scope of what is actually being checked here (i.e., the bond itself is directly a bridge port). -J >+ >+ if (bond_slave_has_mac_rx(bond, eth_data->h_source)) >+ return false; >+ >+ return true; >+} >+ > static netdev_tx_t bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond, > struct slave *tx_slave) > { >@@ -1316,7 +1336,8 @@ static netdev_tx_t bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond, > } > > if (tx_slave && bond_slave_can_tx(tx_slave)) { >- if (tx_slave != rcu_access_pointer(bond->curr_active_slave)) { >+ if (tx_slave != rcu_access_pointer(bond->curr_active_slave) && >+ !bond_alb_bridged_mac(bond, eth_data)) { > ether_addr_copy(eth_data->h_source, > tx_slave->dev->dev_addr); > } >-- >2.30.2 > --- -Jay Vosburgh, jay.vosburgh@canonical.com
diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c index 3455f2cc13f2..ce8257c7cbea 100644 --- a/drivers/net/bonding/bond_alb.c +++ b/drivers/net/bonding/bond_alb.c @@ -1302,6 +1302,26 @@ void bond_alb_deinitialize(struct bonding *bond) rlb_deinitialize(bond); } +static bool bond_alb_bridged_mac(struct bonding *bond, struct ethhdr *eth_data) +{ + struct list_head *iter; + struct slave *slave; + + if (BOND_MODE(bond) != BOND_MODE_ALB) + return false; + + /* Don't modify source MACs that do not originate locally + * (e.g.,arrive via a bridge). + */ + if (!netif_is_bridge_port(bond->dev)) + return false; + + if (bond_slave_has_mac_rx(bond, eth_data->h_source)) + return false; + + return true; +} + static netdev_tx_t bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond, struct slave *tx_slave) { @@ -1316,7 +1336,8 @@ static netdev_tx_t bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond, } if (tx_slave && bond_slave_can_tx(tx_slave)) { - if (tx_slave != rcu_access_pointer(bond->curr_active_slave)) { + if (tx_slave != rcu_access_pointer(bond->curr_active_slave) && + !bond_alb_bridged_mac(bond, eth_data)) { ether_addr_copy(eth_data->h_source, tx_slave->dev->dev_addr); }
With a virtual machine behind a bridge on top of a bond, outgoing traffic should retain the VM's source MAC. That works fine most of the time, until doing a failover, and then the MAC gets rewritten to the bond slave's MAC, and the return traffic gets dropped. If we don't rewrite the MAC there, we don't lose any traffic. Cc: Jay Vosburgh <j.vosburgh@gmail.com> Cc: Veaceslav Falico <vfalico@gmail.com> Cc: Andy Gospodarek <andy@greyhouse.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Thomas Davis <tadavis@lbl.gov> Cc: netdev@vger.kernel.org Signed-off-by: Jarod Wilson <jarod@redhat.com> --- drivers/net/bonding/bond_alb.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-)