Re: Re: [RFC net-next 3/6] ethernet: prestera: use eth_hw_addr_set_port()
From: Taras Chornyi [C] <hidden>
Date: 2021-10-18 16:54:15
---------------------------------------------------------------------- On Fri, Oct 15, 2021 at 12:38:45PM -0700, Jakub Kicinski wrote:
quoted hunk ↗ jump to hunk
Commit 406f42fa0d3c ("net-next: When a bond have a massive amount of VLANs...") introduced a rbtree for faster Ethernet address look up. To maintain netdev->dev_addr in this tree we need to make all the writes to it got through appropriate helpers. We need to make sure the last byte is zeroed. Signed-off-by: Jakub Kicinski <kuba@kernel.org> --- CC: vkochan@marvell.com CC: tchornyi@marvell.com --- drivers/net/ethernet/marvell/prestera/prestera_main.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)diff --git a/drivers/net/ethernet/marvell/prestera/prestera_main.c b/drivers/net/ethernet/marvell/prestera/prestera_main.c index b667f560b931..7d179927dabe 100644 --- a/drivers/net/ethernet/marvell/prestera/prestera_main.c +++ b/drivers/net/ethernet/marvell/prestera/prestera_main.c@@ -290,6 +290,7 @@ static int prestera_port_create(struct prestera_switch *sw, u32 id) { struct prestera_port *port; struct net_device *dev; + u8 addr[ETH_ALEN] = {}; int err; dev = alloc_etherdev(sizeof(*port));@@ -341,8 +342,8 @@ static int prestera_port_create(struct prestera_switch *sw, u32 id) /* firmware requires that port's MAC address consist of the first * 5 bytes of the base MAC address */ - memcpy(dev->dev_addr, sw->base_mac, dev->addr_len - 1); - dev->dev_addr[dev->addr_len - 1] = port->fp_id; + memcpy(addr, sw->base_mac, dev->addr_len - 1);
This code is a bit buggy. We do care about the last byte of the base mac address. For example if base mac is xx:xx:xx:xx:xx:10 first port mac should be xx:xx:xx:xx:xx:11
+ eth_hw_addr_set_port(dev, addr, port->fp_id);
Instead of having yet another temporary copy, can't we zero out sw->base_mac[ETH_ALEN - 1] in prestera_switch_set_base_mac_addr()?
err = prestera_hw_port_mac_set(port, dev->dev_addr);
if (err) {
--
2.31.1