Re: [dpdk-dev] [PATCH v2] ixgbe: Drop flow control frames from VFs

["Zhang, Helin" <helin.zhang@intel.com>]

> -----Original Message-----
> From: Lu, Wenzhuo
> Sent: Thursday, October 22, 2015 3:34 PM
> To: dev@dpdk.org
> Cc: Zhang, Helin; Lu, Wenzhuo
> Subject: [PATCH v2] ixgbe: Drop flow control frames from VFs
> 
> This patch will drop flow control frames from being transmitted from VSIs.
> With this patch in place a malicious VF cannot send flow control or PFC packets
> out on the wire.
> 
> V2:
> Reword the comments.
> 
> Signed-off-by: Wenzhuo Lu <wenzhuo.lu@intel.com>
> ---
>  drivers/net/ixgbe/ixgbe_pf.c | 43
> +++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 43 insertions(+)
> 
> diff --git a/drivers/net/ixgbe/ixgbe_pf.c b/drivers/net/ixgbe/ixgbe_pf.c index
> fd1c4ca..b33f4e9 100644
> --- a/drivers/net/ixgbe/ixgbe_pf.c
> +++ b/drivers/net/ixgbe/ixgbe_pf.c
> @@ -55,6 +55,7 @@
>  #define IXGBE_MAX_VFTA     (128)
>  #define IXGBE_VF_MSG_SIZE_DEFAULT 1
>  #define IXGBE_VF_GET_QUEUE_MSG_SIZE 5
> +#define IXGBE_ETHERTYPE_FLOW_CTRL 0x8808
> 
>  static inline uint16_t
>  dev_num_vf(struct rte_eth_dev *eth_dev) @@ -166,6 +167,46 @@ void
> ixgbe_pf_host_uninit(struct rte_eth_dev *eth_dev)
>  	*vfinfo = NULL;
>  }
> 
> +static void
> +ixgbe_add_tx_flow_control_drop_filter(struct rte_eth_dev *eth_dev) {
> +	struct ixgbe_hw *hw =
> +		IXGBE_DEV_PRIVATE_TO_HW(eth_dev->data->dev_private);
> +	struct ixgbe_filter_info *filter_info =
> +		IXGBE_DEV_PRIVATE_TO_FILTER_INFO(eth_dev->data->dev_private);
> +	uint16_t vf_num;
> +	int i;
> +
> +	/* occupy an entity of ether type filter */
> +	for (i = 0; i < IXGBE_MAX_ETQF_FILTERS; i++) {
> +		if (!(filter_info->ethertype_mask & (1 << i))) {
> +			filter_info->ethertype_mask |= 1 << i;
> +			filter_info->ethertype_filters[i] =
> +				IXGBE_ETHERTYPE_FLOW_CTRL;
> +			break;
> +		}
> +	}
> +	if (i == IXGBE_MAX_ETQF_FILTERS) {
> +		RTE_LOG(ERR, PMD, "Cannot find an unused ether type filter"
> +				" entity for flow control.\n");
> +		return;
> +	}
> +
> +	if (hw->mac.ops.set_ethertype_anti_spoofing) {
> +		IXGBE_WRITE_REG(hw, IXGBE_ETQF(i),
> +				(IXGBE_ETQF_FILTER_EN |
> +				IXGBE_ETQF_TX_ANTISPOOF |
> +				IXGBE_ETHERTYPE_FLOW_CTRL));
> +
> +		vf_num = dev_num_vf(eth_dev);
> +		for (i = 0; i < vf_num; i++) {
> +			hw->mac.ops.set_ethertype_anti_spoofing(hw, true, i);
> +		}
> +	}
ixgbe_set_ethertype_anti_spoofing() is exposed by ixgbe_api.h, and can be used directly.
I think we need a return value for above function, and then the caller can check it.
If it fails, does it need to return out, or just skip the failure?
In addition, is this operation only for x550, right? If yes, it may need a check above.

Regards,
Helin

> +
> +	return;
> +}
> +
>  int ixgbe_pf_host_configure(struct rte_eth_dev *eth_dev)  {
>  	uint32_t vtctl, fcrth;
> @@ -262,6 +303,8 @@ int ixgbe_pf_host_configure(struct rte_eth_dev
> *eth_dev)
>  		IXGBE_WRITE_REG(hw, IXGBE_FCRTH_82599(i), fcrth);
>  	}
> 
> +	ixgbe_add_tx_flow_control_drop_filter(eth_dev);
> +
>  	return 0;
>  }
> 
> --
> 1.9.3