[PATCH net-next v2] net/faraday: Disallow using reversed MAC address from hardware

[PATCH net-next v2] net/faraday: Disallow using reversed MAC address from hardware

[Gavin Shan]

The initial MAC address is retrieved from hardware if it's not
provided by device-tree. The reserved MAC address from hardware
will be used if non-reserved MAC address is invalid. It will
cause mismatched MAC address seen by hardware and software.

This disallows using the reserved hardware MAC address to avoid
the mismatched MAC address seen by hardware and software.

Fixes: 113ce107afe9 ("net/faraday: Read MAC address from chip")
Suggested-by: David Laight <David.Laight@ACULAB.COM>
Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
---
v2: Add "net-next" in the subject
---
 drivers/net/ethernet/faraday/ftgmac100.c | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
index 2d4c7ea..36361f8 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c
@@ -163,15 +163,6 @@ static void ftgmac100_setup_mac(struct ftgmac100 *priv)
 	mac[4] = (l >> 8) & 0xff;
 	mac[5] = l & 0xff;
 
-	if (!is_valid_ether_addr(mac)) {
-		mac[5] = (m >> 8) & 0xff;
-		mac[4] = m & 0xff;
-		mac[3] = (l >> 24) & 0xff;
-		mac[2] = (l >> 16) & 0xff;
-		mac[1] = (l >>  8) & 0xff;
-		mac[0] = l & 0xff;
-	}
-
 	if (is_valid_ether_addr(mac)) {
 		ether_addr_copy(priv->netdev->dev_addr, mac);
 		dev_info(priv->dev, "Read MAC address %pM from chip\n", mac);
-- 
2.1.0

Re: [PATCH net-next v2] net/faraday: Disallow using reversed MAC address from hardware

[David Miller]

From: Gavin Shan <gwshan@linux.vnet.ibm.com>
Date: Thu, 21 Jul 2016 11:42:54 +1000

> The initial MAC address is retrieved from hardware if it's not
> provided by device-tree. The reserved MAC address from hardware
> will be used if non-reserved MAC address is invalid. It will
> cause mismatched MAC address seen by hardware and software.
> 
> This disallows using the reserved hardware MAC address to avoid
> the mismatched MAC address seen by hardware and software.
> 
> Fixes: 113ce107afe9 ("net/faraday: Read MAC address from chip")
> Suggested-by: David Laight <David.Laight@ACULAB.COM>
> Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
> ---
> v2: Add "net-next" in the subject

Makes sense, applied, thanks.

Re: [PATCH net-next v2] net/faraday: Disallow using reversed MAC address from hardware

[Andrew Lunn]

On Thu, Jul 21, 2016 at 11:42:54AM +1000, Gavin Shan wrote:
> The initial MAC address is retrieved from hardware if it's not
> provided by device-tree. The reserved MAC address from hardware
> will be used if non-reserved MAC address is invalid. It will
> cause mismatched MAC address seen by hardware and software.
> 
> This disallows using the reserved hardware MAC address to avoid
> the mismatched MAC address seen by hardware and software.
> 
> Fixes: 113ce107afe9 ("net/faraday: Read MAC address from chip")
> Suggested-by: David Laight <David.Laight@ACULAB.COM>
> Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>

Too late now, since it has been accepted, but the subject line says
reversed, not reserved.

	  Andrew

Re: [PATCH net-next v2] net/faraday: Disallow using reversed MAC address from hardware

[Gavin Shan]

On Thu, Jul 21, 2016 at 04:01:09PM +0200, Andrew Lunn wrote:
>On Thu, Jul 21, 2016 at 11:42:54AM +1000, Gavin Shan wrote:
>> The initial MAC address is retrieved from hardware if it's not
>> provided by device-tree. The reserved MAC address from hardware
>> will be used if non-reserved MAC address is invalid. It will
>> cause mismatched MAC address seen by hardware and software.
>> 
>> This disallows using the reserved hardware MAC address to avoid
>> the mismatched MAC address seen by hardware and software.
>> 
>> Fixes: 113ce107afe9 ("net/faraday: Read MAC address from chip")
>> Suggested-by: David Laight <David.Laight@ACULAB.COM>
>> Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
>
>Too late now, since it has been accepted, but the subject line says
>reversed, not reserved.
>

Yes, It should be reversed, not reserved in the commit log.

Thanks,
Gavin