Fw: [PATCH] e100: Fix inconsistency in bad frames handling

Fw: [PATCH] e100: Fix inconsistency in bad frames handling

[Andrew Morton]

Begin forwarded message:

Date: Sun, 5 Jun 2011 03:14:49 +0200
From: Andrea Merello <andrea.merello@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: [PATCH] e100: Fix inconsistency in bad frames handling


Hello!

In e100 driver it seems that the intention was to accept bad frames in
promiscuous mode and loopback mode.
I think this is evident because of the following code in the driver:

if (nic->flags & promiscuous || nic->loopback) {
               config->rx_save_bad_frames = 0x1;       /* 1=save, 0=discard */
               config->rx_discard_short_frames = 0x0;  /* 1=discard, 0=save */
               config->promiscuous_mode = 0x1;         /* 1=on, 0=off */
       }


However this intention is not really realized because bad frames are
discarded later by SW check.
This patch finally honors the above intention, making the RX code to
let bad frames to pass when the NIC is in promiscuous or loopback
mode.

This helped me a lot to debug an FPGA ethernet core.
Maybe it can be also useful to someone else..

Thanks
Andrea

 --- drivers/net/e100_orig.c     2011-06-14 23:29:38.322267075 +0200
+++ drivers/net/e100.c  2011-06-14 23:34:10.700791472 +0200
@@ -1975,7 +1975,8 @@ static int e100_rx_indicate(struct nic *
       skb_put(skb, actual_size);
       skb->protocol = eth_type_trans(skb, nic->netdev);

-       if (unlikely(!(rfd_status & cb_ok))) {
+       if (unlikely(!(nic->flags & promiscuous || nic->loopback) &&
+           !(rfd_status & cb_ok))) {
               /* Don't indicate if hardware indicates errors */
               dev_kfree_skb_any(skb);
       } else if (actual_size > ETH_DATA_LEN + VLAN_ETH_HLEN) {
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: Fw: [PATCH] e100: Fix inconsistency in bad frames handling

[Eric Dumazet]

Le lundi 06 juin 2011 à 21:44 -0700, Andrew Morton a écrit :
> 
> Begin forwarded message:
> 
> Date: Sun, 5 Jun 2011 03:14:49 +0200
> From: Andrea Merello <andrea.merello@gmail.com>
> To: linux-kernel@vger.kernel.org
> Subject: [PATCH] e100: Fix inconsistency in bad frames handling
> 
> 
> Hello!
> 
> In e100 driver it seems that the intention was to accept bad frames in
> promiscuous mode and loopback mode.
> I think this is evident because of the following code in the driver:
> 
> if (nic->flags & promiscuous || nic->loopback) {
>                config->rx_save_bad_frames = 0x1;       /* 1=save, 0=discard */
>                config->rx_discard_short_frames = 0x0;  /* 1=discard, 0=save */
>                config->promiscuous_mode = 0x1;         /* 1=on, 0=off */
>        }
> 
> 
> However this intention is not really realized because bad frames are
> discarded later by SW check.
> This patch finally honors the above intention, making the RX code to
> let bad frames to pass when the NIC is in promiscuous or loopback
> mode.
> 
> This helped me a lot to debug an FPGA ethernet core.
> Maybe it can be also useful to someone else..
> 
> Thanks
> Andrea
> 
>  --- drivers/net/e100_orig.c     2011-06-14 23:29:38.322267075 +0200
> +++ drivers/net/e100.c  2011-06-14 23:34:10.700791472 +0200
> @@ -1975,7 +1975,8 @@ static int e100_rx_indicate(struct nic *
>        skb_put(skb, actual_size);
>        skb->protocol = eth_type_trans(skb, nic->netdev);
> 
> -       if (unlikely(!(rfd_status & cb_ok))) {
> +       if (unlikely(!(nic->flags & promiscuous || nic->loopback) &&
> +           !(rfd_status & cb_ok))) {
>                /* Don't indicate if hardware indicates errors */
>                dev_kfree_skb_any(skb);
>        } else if (actual_size > ETH_DATA_LEN + VLAN_ETH_HLEN) {


Thanks Andrew, subject already opened on netdev :)

http://www.spinics.net/lists/netdev/msg166301.html

Lets close this thread and continue on previous one ?