[netdevice] Allow duplicate MAC addresses
Many laptops now include the ability to specify a "system-specific MAC
address" (also known as "pass-through MAC"), which is supposed to be
used for both the onboard NIC and for any attached docking station or
other USB NIC. This is intended to simplify interoperability with
software or hardware that relies on a MAC address to recognise an
individual machine: for example, a deployment server may associate the
MAC address with a particular operating system image to be deployed.
This therefore creates legitimate situations in which duplicate MAC
addresses may exist within the same system. Remove the code that
rejects attempts to register a network device with a duplicate MAC.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
diff --git a/src/drivers/net/ecm.c b/src/drivers/net/ecm.c
index 68ac962..ab1f983 100644
--- a/src/drivers/net/ecm.c
+++ b/src/drivers/net/ecm.c
@@ -121,10 +121,9 @@
}
/* Apply system-specific MAC address as current link-layer
- * address, if present and not already used.
+ * address, if present.
*/
- if ( ( ( rc = acpi_mac ( amac ) ) == 0 ) &&
- ! find_netdev_by_ll_addr ( ðernet_protocol, amac ) ) {
+ if ( ( rc = acpi_mac ( amac ) ) == 0 ) {
memcpy ( netdev->ll_addr, amac, ETH_ALEN );
DBGC ( usb, "USB %s using system-specific MAC %s\n",
func->name, eth_ntoa ( netdev->ll_addr ) );
diff --git a/src/include/ipxe/netdevice.h b/src/include/ipxe/netdevice.h
index 29358db..af932c2 100644
--- a/src/include/ipxe/netdevice.h
+++ b/src/include/ipxe/netdevice.h
@@ -729,8 +729,6 @@
extern struct net_device * find_netdev_by_scope_id ( unsigned int scope_id );
extern struct net_device * find_netdev_by_location ( unsigned int bus_type,
unsigned int location );
-extern struct net_device *
-find_netdev_by_ll_addr ( struct ll_protocol *ll_protocol, const void *ll_addr );
extern struct net_device * last_opened_netdev ( void );
extern int net_tx ( struct io_buffer *iobuf, struct net_device *netdev,
struct net_protocol *net_protocol, const void *ll_dest,
diff --git a/src/net/netdevice.c b/src/net/netdevice.c
index 597c622..07961bf 100644
--- a/src/net/netdevice.c
+++ b/src/net/netdevice.c
@@ -735,18 +735,6 @@
ll_protocol->ll_header_len );
}
- /* Reject network devices that are already available via a
- * different hardware device.
- */
- duplicate = find_netdev_by_ll_addr ( ll_protocol, netdev->ll_addr );
- if ( duplicate && ( duplicate->dev != netdev->dev ) ) {
- DBGC ( netdev, "NETDEV rejecting duplicate (phys %s) of %s "
- "(phys %s)\n", netdev->dev->name, duplicate->name,
- duplicate->dev->name );
- rc = -EEXIST;
- goto err_duplicate;
- }
-
/* Reject named network devices that already exist */
if ( netdev->name[0] && ( duplicate = find_netdev ( netdev->name ) ) ) {
DBGC ( netdev, "NETDEV rejecting duplicate name %s\n",
@@ -1003,27 +991,6 @@
}
/**
- * Get network device by link-layer address
- *
- * @v ll_protocol Link-layer protocol
- * @v ll_addr Link-layer address
- * @ret netdev Network device, or NULL
- */
-struct net_device * find_netdev_by_ll_addr ( struct ll_protocol *ll_protocol,
- const void *ll_addr ) {
- struct net_device *netdev;
-
- list_for_each_entry ( netdev, &net_devices, list ) {
- if ( ( netdev->ll_protocol == ll_protocol ) &&
- ( memcmp ( netdev->ll_addr, ll_addr,
- ll_protocol->ll_addr_len ) == 0 ) )
- return netdev;
- }
-
- return NULL;
-}
-
-/**
* Get most recently opened network device
*
* @ret netdev Most recently opened network device, or NULL
