Track the number of indirection table entries the user originally
provided (context 0/default as well!).

Replace IFF_RXFH_CONFIGURED with rss_indir_user_size: the flag is
redundant now that user_size captures the same information.

Add ethtool_rxfh_indir_clear() for drivers that must reset the
indirection table.

Convert bnxt and mlx5 to use it.

Signed-off-by: Björn Töpel <bjorn@kernel.org>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c     |  2 +-
 .../net/ethernet/mellanox/mlx5/core/en_main.c |  2 +-
 include/linux/ethtool.h                       |  7 ++++++
 include/linux/netdevice.h                     |  7 +-----
 net/ethtool/common.c                          | 20 ++++++++++++++++
 net/ethtool/ioctl.c                           |  9 +++----
 net/ethtool/rss.c                             | 24 ++++++++++++-------
 7 files changed, 51 insertions(+), 20 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index c982aac714d1..04da3f708b4b 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -8117,7 +8117,7 @@ static int __bnxt_reserve_rings(struct bnxt *bp)
 		     bnxt_get_nr_rss_ctxs(bp, rx_rings) ||
 		     bnxt_get_max_rss_ring(bp) >= rx_rings)) {
 			netdev_warn(bp->dev, "RSS table entries reverting to default\n");
-			bp->dev->priv_flags &= ~IFF_RXFH_CONFIGURED;
+			ethtool_rxfh_indir_clear(bp->dev);
 		}
 	}
 	bp->rx_nr_rings = rx_rings;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index f7009da94f0b..1a010a115cff 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -6488,7 +6488,7 @@ int mlx5e_attach_netdev(struct mlx5e_priv *priv)
 		/* Reducing the number of channels - RXFH has to be reset, and
 		 * mlx5e_num_channels_changed below will build the RQT.
 		 */
-		priv->netdev->priv_flags &= ~IFF_RXFH_CONFIGURED;
+		ethtool_rxfh_indir_clear(priv->netdev);
 		priv->channels.params.num_channels = max_nch;
 		if (priv->channels.params.mqprio.mode == TC_MQPRIO_MODE_CHANNEL) {
 			mlx5_core_warn(priv->mdev, "MLX5E: Disabling MQPRIO channel mode\n");
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 83c375840835..d4d3c57bc7c0 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -176,6 +176,8 @@ static inline u32 ethtool_rxfh_indir_default(u32 index, u32 n_rx_rings)
  * struct ethtool_rxfh_context - a custom RSS context configuration
  * @indir_size: Number of u32 entries in indirection table
  * @key_size: Size of hash key, in bytes
+ * @indir_user_size: number of user provided entries for the
+ *	indirection table
  * @priv_size: Size of driver private data, in bytes
  * @hfunc: RSS hash function identifier.  One of the %ETH_RSS_HASH_*
  * @input_xfrm: Defines how the input data is transformed. Valid values are one
@@ -186,6 +188,7 @@ static inline u32 ethtool_rxfh_indir_default(u32 index, u32 n_rx_rings)
 struct ethtool_rxfh_context {
 	u32 indir_size;
 	u32 key_size;
+	u32 indir_user_size;
 	u16 priv_size;
 	u8 hfunc;
 	u8 input_xfrm;
@@ -214,6 +217,7 @@ static inline u8 *ethtool_rxfh_context_key(struct ethtool_rxfh_context *ctx)
 }
 
 void ethtool_rxfh_context_lost(struct net_device *dev, u32 context_id);
+void ethtool_rxfh_indir_clear(struct net_device *dev);
 
 struct link_mode_info {
 	int	speed;
@@ -1333,12 +1337,15 @@ int ethtool_virtdev_set_link_ksettings(struct net_device *dev,
  * @rss_ctx:		XArray of custom RSS contexts
  * @rss_lock:		Protects entries in @rss_ctx.  May be taken from
  *			within RTNL.
+ * @rss_indir_user_size: Number of user provided entries for the default
+ *			 (context 0) indirection table.
  * @wol_enabled:	Wake-on-LAN is enabled
  * @module_fw_flash_in_progress: Module firmware flashing is in progress.
  */
 struct ethtool_netdev_state {
 	struct xarray		rss_ctx;
 	struct mutex		rss_lock;
+	u32			rss_indir_user_size;
 	unsigned		wol_enabled:1;
 	unsigned		module_fw_flash_in_progress:1;
 };
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index ae269a2e7f4d..dc28954d4df6 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1714,7 +1714,6 @@ struct net_device_ops {
  * @IFF_OPENVSWITCH: device is a Open vSwitch master
  * @IFF_L3MDEV_SLAVE: device is enslaved to an L3 master device
  * @IFF_TEAM: device is a team device
- * @IFF_RXFH_CONFIGURED: device has had Rx Flow indirection table configured
  * @IFF_PHONY_HEADROOM: the headroom value is controlled by an external
  *	entity (i.e. the master device for bridged veth)
  * @IFF_MACSEC: device is a MACsec device
@@ -1750,7 +1749,6 @@ enum netdev_priv_flags {
 	IFF_OPENVSWITCH			= 1<<20,
 	IFF_L3MDEV_SLAVE		= 1<<21,
 	IFF_TEAM			= 1<<22,
-	IFF_RXFH_CONFIGURED		= 1<<23,
 	IFF_PHONY_HEADROOM		= 1<<24,
 	IFF_MACSEC			= 1<<25,
 	IFF_NO_RX_HANDLER		= 1<<26,
@@ -5568,10 +5566,7 @@ static inline bool netif_is_lag_port(const struct net_device *dev)
 	return netif_is_bond_slave(dev) || netif_is_team_port(dev);
 }
 
-static inline bool netif_is_rxfh_configured(const struct net_device *dev)
-{
-	return dev->priv_flags & IFF_RXFH_CONFIGURED;
-}
+bool netif_is_rxfh_configured(const struct net_device *dev);
 
 static inline bool netif_is_failover(const struct net_device *dev)
 {
diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index e252cf20c22f..ee91f1155830 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -1204,6 +1204,26 @@ void ethtool_rxfh_context_lost(struct net_device *dev, u32 context_id)
 }
 EXPORT_SYMBOL(ethtool_rxfh_context_lost);
 
+bool netif_is_rxfh_configured(const struct net_device *dev)
+{
+	return dev->ethtool->rss_indir_user_size;
+}
+EXPORT_SYMBOL(netif_is_rxfh_configured);
+
+/**
+ * ethtool_rxfh_indir_clear - Clear user indirection table config
+ * @dev: network device
+ *
+ * Mark the default RSS context indirection table as unconfigured and
+ * send an %ETHTOOL_MSG_RSS_NTF notification.
+ */
+void ethtool_rxfh_indir_clear(struct net_device *dev)
+{
+	dev->ethtool->rss_indir_user_size = 0;
+	ethtool_rss_notify(dev, ETHTOOL_MSG_RSS_NTF, 0);
+}
+EXPORT_SYMBOL(ethtool_rxfh_indir_clear);
+
 enum ethtool_link_medium ethtool_str_to_medium(const char *str)
 {
 	int i;
diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index ff4b4780d6af..3d31a5a041e3 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -1404,9 +1404,9 @@ static noinline_for_stack int ethtool_set_rxfh_indir(struct net_device *dev,
 
 	/* indicate whether rxfh was set to default */
 	if (user_size == 0)
-		dev->priv_flags &= ~IFF_RXFH_CONFIGURED;
+		dev->ethtool->rss_indir_user_size = 0;
 	else
-		dev->priv_flags |= IFF_RXFH_CONFIGURED;
+		dev->ethtool->rss_indir_user_size = rxfh_dev.indir_size;
 
 out_unlock:
 	mutex_unlock(&dev->ethtool->rss_lock);
@@ -1721,9 +1721,9 @@ static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev,
 	if (!rxfh_dev.rss_context) {
 		/* indicate whether rxfh was set to default */
 		if (rxfh.indir_size == 0)
-			dev->priv_flags &= ~IFF_RXFH_CONFIGURED;
+			dev->ethtool->rss_indir_user_size = 0;
 		else if (rxfh.indir_size != ETH_RXFH_INDIR_NO_CHANGE)
-			dev->priv_flags |= IFF_RXFH_CONFIGURED;
+			dev->ethtool->rss_indir_user_size = dev_indir_size;
 	}
 	/* Update rss_ctx tracking */
 	if (rxfh_dev.rss_delete) {
@@ -1736,6 +1736,7 @@ static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev,
 			ctx->indir_configured =
 				rxfh.indir_size &&
 				rxfh.indir_size != ETH_RXFH_INDIR_NO_CHANGE;
+			ctx->indir_user_size = dev_indir_size;
 		}
 		if (rxfh_dev.key) {
 			memcpy(ethtool_rxfh_context_key(ctx), rxfh_dev.key,
diff --git a/net/ethtool/rss.c b/net/ethtool/rss.c
index da5934cceb07..e6fc6e64fb27 100644
--- a/net/ethtool/rss.c
+++ b/net/ethtool/rss.c
@@ -686,7 +686,7 @@ rss_set_prep_indir(struct net_device *dev, struct genl_info *info,
 
 	*mod |= memcmp(rxfh->indir, data->indir_table, data->indir_size);
 
-	return 0;
+	return user_size;
 
 err_free:
 	kfree(rxfh->indir);
@@ -833,6 +833,7 @@ ethnl_rss_set(struct ethnl_req_info *req_info, struct genl_info *info)
 	struct nlattr **tb = info->attrs;
 	struct rss_reply_data data = {};
 	const struct ethtool_ops *ops;
+	u32 indir_user_size;
 	int ret;
 
 	ops = dev->ethtool_ops;
@@ -845,8 +846,9 @@ ethnl_rss_set(struct ethnl_req_info *req_info, struct genl_info *info)
 	rxfh.rss_context = request->rss_context;
 
 	ret = rss_set_prep_indir(dev, info, &data, &rxfh, &indir_reset, &mod);
-	if (ret)
+	if (ret < 0)
 		goto exit_clean_data;
+	indir_user_size = ret;
 	indir_mod = !!tb[ETHTOOL_A_RSS_INDIR];
 
 	rxfh.hfunc = data.hfunc;
@@ -889,12 +891,15 @@ ethnl_rss_set(struct ethnl_req_info *req_info, struct genl_info *info)
 	if (ret)
 		goto exit_unlock;
 
-	if (ctx)
+	if (ctx) {
 		rss_set_ctx_update(ctx, tb, &data, &rxfh);
-	else if (indir_reset)
-		dev->priv_flags &= ~IFF_RXFH_CONFIGURED;
-	else if (indir_mod)
-		dev->priv_flags |= IFF_RXFH_CONFIGURED;
+		if (indir_user_size)
+			ctx->indir_user_size = indir_user_size;
+	} else if (indir_reset) {
+		dev->ethtool->rss_indir_user_size = 0;
+	} else if (indir_mod) {
+		dev->ethtool->rss_indir_user_size = indir_user_size;
+	}
 
 exit_unlock:
 	mutex_unlock(&dev->ethtool->rss_lock);
@@ -999,6 +1004,7 @@ int ethnl_rss_create_doit(struct sk_buff *skb, struct genl_info *info)
 	const struct ethtool_ops *ops;
 	struct rss_req_info req = {};
 	struct net_device *dev;
+	u32 indir_user_size;
 	struct sk_buff *rsp;
 	void *hdr;
 	u32 limit;
@@ -1035,8 +1041,9 @@ int ethnl_rss_create_doit(struct sk_buff *skb, struct genl_info *info)
 		goto exit_ops;
 
 	ret = rss_set_prep_indir(dev, info, &data, &rxfh, &indir_dflt, &mod);
-	if (ret)
+	if (ret < 0)
 		goto exit_clean_data;
+	indir_user_size = ret;
 
 	ethnl_update_u8(&rxfh.hfunc, tb[ETHTOOL_A_RSS_HFUNC], &mod);
 
@@ -1080,6 +1087,7 @@ int ethnl_rss_create_doit(struct sk_buff *skb, struct genl_info *info)
 
 	/* Store the config from rxfh to Xarray.. */
 	rss_set_ctx_update(ctx, tb, &data, &rxfh);
+	ctx->indir_user_size = indir_user_size;
 	/* .. copy from Xarray to data. */
 	__rss_prepare_ctx(dev, &data, ctx);
 
-- 
2.53.0

On Wed, 18 Mar 2026 13:25:58 +0100 Björn Töpel wrote:
> diff --git a/net/ethtool/common.c b/net/ethtool/common.c
> index e252cf20c22f..ee91f1155830 100644
> --- a/net/ethtool/common.c
> +++ b/net/ethtool/common.c
> @@ -1204,6 +1204,26 @@ void ethtool_rxfh_context_lost(struct net_device *dev, u32 context_id)
>  }
>  EXPORT_SYMBOL(ethtool_rxfh_context_lost);
>  
> +bool netif_is_rxfh_configured(const struct net_device *dev)
> +{
> +	return dev->ethtool->rss_indir_user_size;
> +}
> +EXPORT_SYMBOL(netif_is_rxfh_configured);
> +
> +/**
> + * ethtool_rxfh_indir_clear - Clear user indirection table config
> + * @dev: network device
> + *
> + * Mark the default RSS context indirection table as unconfigured and
> + * send an %ETHTOOL_MSG_RSS_NTF notification.

If you're adding kdoc you should very clearly state this is function
should only be called if the driver lost the ability to maintain the
indirection table, usually after HW fault recovery reduced the max
queue count.

> + */
> +void ethtool_rxfh_indir_clear(struct net_device *dev)

ethtool_rxfh_indir_lost() would be a better name, it would align with 
ethtool_rxfh_context_lost() right above the code you're adding, right?

> +{

Let's add an error in here like the one we have in
ethtool_rxfh_context_lost(), this should stop arbitrary use.
And you can remove the local warning in bnxt if we do that.

> +	dev->ethtool->rss_indir_user_size = 0;
> +	ethtool_rss_notify(dev, ETHTOOL_MSG_RSS_NTF, 0);
> +}
> +EXPORT_SYMBOL(ethtool_rxfh_indir_clear);
> +
>  enum ethtool_link_medium ethtool_str_to_medium(const char *str)
>  {
>  	int i;