[PATCH iwl-next v2] ice: implement symmetric RSS hash configuration

[PATCH iwl-next v2] ice: implement symmetric RSS hash configuration

[Aleksandr Loktionov]

The driver advertises symmetric RSS support via supported_input_xfrm
but ice_set_rxfh() ignored the input_xfrm parameter, making it
impossible to configure symmetric hashing.

Fix ice_set_rxfh() to check rxfh->input_xfrm and call
ice_set_rss_hfunc() with ICE_AQ_VSI_Q_OPT_RSS_HASH_SYM_TPLZ when
RXH_XFRM_SYM_XOR is requested.

Modify ice_set_rss_vsi_ctx() to use vsi->rss_hfunc instead of
hardcoding ICE_AQ_VSI_Q_OPT_RSS_HASH_TPLZ, and export it for
use by ice_set_rxfh().

The kernel requires get_rxfh_fields() to report symmetric hash
configurations when symmetric transforms are supported. Update
ice_get_rxfh_fields() to return symmetric field configuration
(src+dst IP and ports) for all flow types.

Tested with tools/testing/selftests/drivers/net/hw/rss_input_xfrm.py

Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
---
v1 -> v2 preserve valid symmetric RSS fields.
---
 drivers/net/ethernet/intel/ice/ice_ethtool.c | 45 ++++++++++++++++----
 drivers/net/ethernet/intel/ice/ice_lib.c     |  7 +--
 drivers/net/ethernet/intel/ice/ice_lib.h     |  1 +
 3 files changed, 41 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c
index c6bc29c..27c97ca 100644
--- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
@@ -3008,14 +3008,18 @@ ice_set_rxfh_fields(struct net_device *netdev,
 	return 0;
 }
 
+#define ICE_RSS_ALLOWED_FIELDS	(RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3)
+#define ICE_RSS_L3_PAIR		(RXH_IP_SRC | RXH_IP_DST)
+#define ICE_RSS_L4_PAIR		(RXH_L4_B_0_1 | RXH_L4_B_2_3)
+
 static int
 ice_get_rxfh_fields(struct net_device *netdev, struct ethtool_rxfh_fields *nfc)
 {
 	struct ice_netdev_priv *np = netdev_priv(netdev);
 	struct ice_vsi *vsi = np->vsi;
 	struct ice_pf *pf = vsi->back;
+	u64 l3, l4, hash_flds;
 	struct device *dev;
-	u64 hash_flds;
 	bool symm;
 	u32 hdrs;
 
@@ -3037,8 +3041,10 @@ ice_get_rxfh_fields(struct net_device *netdev, struct ethtool_rxfh_fields *nfc)
 
 	hash_flds = ice_get_rss_cfg(&pf->hw, vsi->idx, hdrs, &symm);
 	if (hash_flds == ICE_HASH_INVALID) {
-		dev_dbg(dev, "No hash fields found for the given header type, vsi num = %d\n",
+		/* Provide default symmetric hash fields when no config exists */
+		dev_dbg(dev, "No RSS config for this flow, using symmetric defaults, vsi num = %d\n",
 			vsi->vsi_num);
+		nfc->data = RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3;
 		return 0;
 	}
 
@@ -3067,6 +3073,13 @@ ice_get_rxfh_fields(struct net_device *netdev, struct ethtool_rxfh_fields *nfc)
 	    hash_flds & ICE_FLOW_HASH_FLD_GTPU_DWN_TEID)
 		nfc->data |= (u64)RXH_GTP_TEID;
 
+	nfc->data &= ICE_RSS_ALLOWED_FIELDS;
+	l3 = nfc->data & ICE_RSS_L3_PAIR;
+	l4 = nfc->data & ICE_RSS_L4_PAIR;
+	if (!nfc->data ||
+	    (l3 && l3 != ICE_RSS_L3_PAIR) ||
+	    (l4 && l4 != ICE_RSS_L4_PAIR))
+		nfc->data = ICE_RSS_ALLOWED_FIELDS;
 	return 0;
 }
 
@@ -3667,7 +3680,6 @@ ice_set_rxfh(struct net_device *netdev, struct ethtool_rxfh_param *rxfh,
 	     struct netlink_ext_ack *extack)
 {
 	struct ice_netdev_priv *np = netdev_priv(netdev);
-	u8 hfunc = ICE_AQ_VSI_Q_OPT_RSS_HASH_TPLZ;
 	struct ice_vsi *vsi = np->vsi;
 	struct ice_pf *pf = vsi->back;
 	struct device *dev;
@@ -3689,13 +3701,28 @@ ice_set_rxfh(struct net_device *netdev, struct ethtool_rxfh_param *rxfh,
 		return -EOPNOTSUPP;
 	}
 
-	/* Update the VSI's hash function */
-	if (rxfh->input_xfrm & RXH_XFRM_SYM_XOR)
-		hfunc = ICE_AQ_VSI_Q_OPT_RSS_HASH_SYM_TPLZ;
+	/* Handle RSS symmetric hash transformation */
+	if (rxfh->input_xfrm != RXH_XFRM_NO_CHANGE) {
+		u8 new_hfunc;
 
-	err = ice_set_rss_hfunc(vsi, hfunc);
-	if (err)
-		return err;
+		if (rxfh->input_xfrm == RXH_XFRM_SYM_XOR)
+			new_hfunc = ICE_AQ_VSI_Q_OPT_RSS_HASH_SYM_TPLZ;
+		else if (!rxfh->input_xfrm)
+			new_hfunc = ICE_AQ_VSI_Q_OPT_RSS_HASH_TPLZ;
+		else
+			return -EOPNOTSUPP;
+
+		if (new_hfunc != vsi->rss_hfunc) {
+			err = ice_set_rss_hfunc(vsi, new_hfunc);
+			if (err) {
+				netdev_err(netdev, "Failed to set RSS hash function\n");
+				return err;
+			}
+			netdev_dbg(netdev, "RSS hash function: %sToeplitz\n",
+				    new_hfunc == ICE_AQ_VSI_Q_OPT_RSS_HASH_SYM_TPLZ ?
+				    "Symmetric " : "");
+		}
+	}
 
 	if (rxfh->key) {
 		if (!vsi->rss_hkey_user) {
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c b/drivers/net/ethernet/intel/ice/ice_lib.c
index d921269..5b1934b 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_lib.c
@@ -1155,7 +1155,7 @@ static void ice_set_fd_vsi_ctx(struct ice_vsi_ctx *ctxt, struct ice_vsi *vsi)
  * @ctxt: the VSI context being set
  * @vsi: the VSI being configured
  */
-static void ice_set_rss_vsi_ctx(struct ice_vsi_ctx *ctxt, struct ice_vsi *vsi)
+void ice_set_rss_vsi_ctx(struct ice_vsi_ctx *ctxt, struct ice_vsi *vsi)
 {
 	u8 lut_type, hash_type;
 	struct device *dev;
@@ -1181,8 +1181,9 @@ static void ice_set_rss_vsi_ctx(struct ice_vsi_ctx *ctxt, struct ice_vsi *vsi)
 		return;
 	}
 
-	hash_type = ICE_AQ_VSI_Q_OPT_RSS_HASH_TPLZ;
-	vsi->rss_hfunc = hash_type;
+	if (!vsi->rss_hfunc)
+		vsi->rss_hfunc = ICE_AQ_VSI_Q_OPT_RSS_HASH_TPLZ;
+	hash_type = vsi->rss_hfunc;
 
 	ctxt->info.q_opt_rss =
 		FIELD_PREP(ICE_AQ_VSI_Q_OPT_RSS_LUT_M, lut_type) |
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.h b/drivers/net/ethernet/intel/ice/ice_lib.h
index 49454d98..29ba335 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.h
+++ b/drivers/net/ethernet/intel/ice/ice_lib.h
@@ -46,6 +46,7 @@ void ice_vsi_delete(struct ice_vsi *vsi);
 int ice_vsi_cfg_tc(struct ice_vsi *vsi, u8 ena_tc);
 
 int ice_vsi_cfg_rss_lut_key(struct ice_vsi *vsi);
+void ice_set_rss_vsi_ctx(struct ice_vsi_ctx *ctxt, struct ice_vsi *vsi);
 
 void ice_vsi_cfg_netdev_tc(struct ice_vsi *vsi, u8 ena_tc);
 
-- 
2.52.0

Re: [PATCH iwl-next v2] ice: implement symmetric RSS hash configuration

[Simon Horman]

On Tue, Feb 17, 2026 at 02:00:39PM +0100, Aleksandr Loktionov wrote:
> The driver advertises symmetric RSS support via supported_input_xfrm
> but ice_set_rxfh() ignored the input_xfrm parameter, making it
> impossible to configure symmetric hashing.
> 
> Fix ice_set_rxfh() to check rxfh->input_xfrm and call
> ice_set_rss_hfunc() with ICE_AQ_VSI_Q_OPT_RSS_HASH_SYM_TPLZ when
> RXH_XFRM_SYM_XOR is requested.
> 
> Modify ice_set_rss_vsi_ctx() to use vsi->rss_hfunc instead of
> hardcoding ICE_AQ_VSI_Q_OPT_RSS_HASH_TPLZ, and export it for
> use by ice_set_rxfh().
> 
> The kernel requires get_rxfh_fields() to report symmetric hash
> configurations when symmetric transforms are supported. Update
> ice_get_rxfh_fields() to return symmetric field configuration
> (src+dst IP and ports) for all flow types.
> 
> Tested with tools/testing/selftests/drivers/net/hw/rss_input_xfrm.py
> 
> Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
> ---
> v1 -> v2 preserve valid symmetric RSS fields.

Thanks for the update.

Reviewed-by: Simon Horman <horms@kernel.org>

Re: [Intel-wired-lan] [PATCH iwl-next v2] ice: implement symmetric RSS hash configuration

[Marcin Szycik]

On 17.02.2026 14:00, Aleksandr Loktionov wrote:
> The driver advertises symmetric RSS support via supported_input_xfrm
> but ice_set_rxfh() ignored the input_xfrm parameter, making it

s/ignored/ignores/

> impossible to configure symmetric hashing.
> 
> Fix ice_set_rxfh() to check rxfh->input_xfrm and call
> ice_set_rss_hfunc() with ICE_AQ_VSI_Q_OPT_RSS_HASH_SYM_TPLZ when
> RXH_XFRM_SYM_XOR is requested.
> 
> Modify ice_set_rss_vsi_ctx() to use vsi->rss_hfunc instead of
> hardcoding ICE_AQ_VSI_Q_OPT_RSS_HASH_TPLZ, and export it for
> use by ice_set_rxfh().
> 
> The kernel requires get_rxfh_fields() to report symmetric hash
> configurations when symmetric transforms are supported. Update
> ice_get_rxfh_fields() to return symmetric field configuration
> (src+dst IP and ports) for all flow types.
> 
> Tested with tools/testing/selftests/drivers/net/hw/rss_input_xfrm.py
> 
> Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
> ---
> v1 -> v2 preserve valid symmetric RSS fields.
> ---
>  drivers/net/ethernet/intel/ice/ice_ethtool.c | 45 ++++++++++++++++----
>  drivers/net/ethernet/intel/ice/ice_lib.c     |  7 +--
>  drivers/net/ethernet/intel/ice/ice_lib.h     |  1 +
>  3 files changed, 41 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c
> index c6bc29c..27c97ca 100644
> --- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
> +++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
> @@ -3008,14 +3008,18 @@ ice_set_rxfh_fields(struct net_device *netdev,
>  	return 0;
>  }
>  
> +#define ICE_RSS_ALLOWED_FIELDS	(RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3)
> +#define ICE_RSS_L3_PAIR		(RXH_IP_SRC | RXH_IP_DST)
> +#define ICE_RSS_L4_PAIR		(RXH_L4_B_0_1 | RXH_L4_B_2_3)
> +
>  static int
>  ice_get_rxfh_fields(struct net_device *netdev, struct ethtool_rxfh_fields *nfc)
>  {
>  	struct ice_netdev_priv *np = netdev_priv(netdev);
>  	struct ice_vsi *vsi = np->vsi;
>  	struct ice_pf *pf = vsi->back;
> +	u64 l3, l4, hash_flds;
>  	struct device *dev;
> -	u64 hash_flds;
>  	bool symm;
>  	u32 hdrs;
>  
> @@ -3037,8 +3041,10 @@ ice_get_rxfh_fields(struct net_device *netdev, struct ethtool_rxfh_fields *nfc)
>  
>  	hash_flds = ice_get_rss_cfg(&pf->hw, vsi->idx, hdrs, &symm);
>  	if (hash_flds == ICE_HASH_INVALID) {
> -		dev_dbg(dev, "No hash fields found for the given header type, vsi num = %d\n",
> +		/* Provide default symmetric hash fields when no config exists */
> +		dev_dbg(dev, "No RSS config for this flow, using symmetric defaults, vsi num = %d\n",
>  			vsi->vsi_num);
> +		nfc->data = RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3;

This is the same as ICE_RSS_ALLOWED_FIELDS, use it or:
#define ICE_RSS_DEFAULT_FIELDS ICE_RSS_ALLOWED_FIELDS

>  		return 0;
>  	}

Thanks,
Marcin

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