diff mbox series

[net-next,v3,06/12] ethtool: rss: don't report key if device doesn't support it

Message ID 20240806193317.1491822-7-kuba@kernel.org (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series ethtool: rss: driver tweaks and netlink context dumps | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; GEN HAS DIFF 2 files changed, 119 insertions(+);
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 35 this patch: 35
netdev/build_tools success Errors and warnings before: 9 this patch: 9
netdev/cc_maintainers warning 8 maintainers not CCed: intel-wired-lan@lists.osuosl.org linux-rdma@vger.kernel.org anthony.l.nguyen@intel.com leon@kernel.org habetsm.xilinx@gmail.com saeedm@nvidia.com linux-net-drivers@amd.com tariqt@nvidia.com
netdev/build_clang success Errors and warnings before: 90 this patch: 90
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1742 this patch: 1742
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 137 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 60 this patch: 60
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-08-07--03-00 (tests: 707)

Commit Message

Jakub Kicinski Aug. 6, 2024, 7:33 p.m. UTC
marvell/otx2 and mvpp2 do not support setting different
keys for different RSS contexts. Contexts have separate
indirection tables but key is shared with all other contexts.
This is likely fine, indirection table is the most important
piece.

Don't report the key-related parameters from such drivers.
This prevents driver-errors, e.g. otx2 always writes
the main key, even when user asks to change per-context key.
The second reason is that without this change tracking
the keys by the core gets complicated. Even if the driver
correctly reject setting key with rss_context != 0,
change of the main key would have to be reflected in
the XArray for all additional contexts.

Since the additional contexts don't have their own keys
not including the attributes (in Netlink speak) seems
intuitive. ethtool CLI seems to deal with it just fine.

Having to set the flag in majority of the drivers is
a bit tedious but not reporting the key is a safer
default.

Reviewed-by: Joe Damato <jdamato@fastly.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
v3:
 - add safety note to the commit message
 - use true in sfc, drop sienna
 - extend kdoc of @rxfh_per_ctx_key
---
 .../net/ethernet/broadcom/bnxt/bnxt_ethtool.c |  1 +
 drivers/net/ethernet/intel/ice/ice_ethtool.c  |  1 +
 .../ethernet/mellanox/mlx5/core/en_ethtool.c  |  1 +
 drivers/net/ethernet/sfc/ef100_ethtool.c      |  1 +
 drivers/net/ethernet/sfc/ethtool.c            |  1 +
 include/linux/ethtool.h                       |  4 +++
 net/ethtool/ioctl.c                           | 25 ++++++++++++++++---
 net/ethtool/rss.c                             | 21 +++++++++++-----
 8 files changed, 45 insertions(+), 10 deletions(-)

Comments

Edward Cree Aug. 8, 2024, 11:26 a.m. UTC | #1
On 06/08/2024 20:33, Jakub Kicinski wrote:
> marvell/otx2 and mvpp2 do not support setting different
> keys for different RSS contexts. Contexts have separate
> indirection tables but key is shared with all other contexts.
> This is likely fine, indirection table is the most important
> piece.
> 
> Don't report the key-related parameters from such drivers.
> This prevents driver-errors, e.g. otx2 always writes
> the main key, even when user asks to change per-context key.
> The second reason is that without this change tracking
> the keys by the core gets complicated. Even if the driver
> correctly reject setting key with rss_context != 0,
> change of the main key would have to be reflected in
> the XArray for all additional contexts.
> 
> Since the additional contexts don't have their own keys
> not including the attributes (in Netlink speak) seems
> intuitive. ethtool CLI seems to deal with it just fine.
> 
> Having to set the flag in majority of the drivers is
> a bit tedious but not reporting the key is a safer
> default.
> 
> Reviewed-by: Joe Damato <jdamato@fastly.com>
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Reviewed-by: Edward Cree <ecree.xilinx@gmail.com>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index 33e8cf0a3764..77621ccfff5e 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -5289,6 +5289,7 @@  void bnxt_ethtool_free(struct bnxt *bp)
 
 const struct ethtool_ops bnxt_ethtool_ops = {
 	.cap_link_lanes_supported	= 1,
+	.rxfh_per_ctx_key		= 1,
 	.rxfh_max_context_id		= BNXT_MAX_ETH_RSS_CTX,
 	.rxfh_indir_space		= BNXT_MAX_RSS_TABLE_ENTRIES_P5,
 	.rxfh_priv_size			= sizeof(struct bnxt_rss_ctx),
diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c
index 8c990c976132..b5b57926cdc0 100644
--- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
@@ -4725,6 +4725,7 @@  static const struct ethtool_ops ice_ethtool_ops = {
 				     ETHTOOL_COALESCE_USE_ADAPTIVE |
 				     ETHTOOL_COALESCE_RX_USECS_HIGH,
 	.cap_rss_sym_xor_supported = true,
+	.rxfh_per_ctx_key	= true,
 	.get_link_ksettings	= ice_get_link_ksettings,
 	.set_link_ksettings	= ice_set_link_ksettings,
 	.get_fec_stats		= ice_get_fec_stats,
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index 0b941482db30..2d514210aaec 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -2593,6 +2593,7 @@  static void mlx5e_get_ts_stats(struct net_device *netdev,
 
 const struct ethtool_ops mlx5e_ethtool_ops = {
 	.cap_rss_ctx_supported	= true,
+	.rxfh_per_ctx_key	= true,
 	.supported_coalesce_params = ETHTOOL_COALESCE_USECS |
 				     ETHTOOL_COALESCE_MAX_FRAMES |
 				     ETHTOOL_COALESCE_USE_ADAPTIVE |
diff --git a/drivers/net/ethernet/sfc/ef100_ethtool.c b/drivers/net/ethernet/sfc/ef100_ethtool.c
index 746b5314acb5..5c2551369812 100644
--- a/drivers/net/ethernet/sfc/ef100_ethtool.c
+++ b/drivers/net/ethernet/sfc/ef100_ethtool.c
@@ -58,6 +58,7 @@  const struct ethtool_ops ef100_ethtool_ops = {
 
 	.get_rxfh_indir_size	= efx_ethtool_get_rxfh_indir_size,
 	.get_rxfh_key_size	= efx_ethtool_get_rxfh_key_size,
+	.rxfh_per_ctx_key	= true,
 	.rxfh_priv_size		= sizeof(struct efx_rss_context_priv),
 	.get_rxfh		= efx_ethtool_get_rxfh,
 	.set_rxfh		= efx_ethtool_set_rxfh,
diff --git a/drivers/net/ethernet/sfc/ethtool.c b/drivers/net/ethernet/sfc/ethtool.c
index 15245720c949..848b1923133a 100644
--- a/drivers/net/ethernet/sfc/ethtool.c
+++ b/drivers/net/ethernet/sfc/ethtool.c
@@ -267,6 +267,7 @@  const struct ethtool_ops efx_ethtool_ops = {
 	.set_rxnfc		= efx_ethtool_set_rxnfc,
 	.get_rxfh_indir_size	= efx_ethtool_get_rxfh_indir_size,
 	.get_rxfh_key_size	= efx_ethtool_get_rxfh_key_size,
+	.rxfh_per_ctx_key	= true,
 	.rxfh_priv_size		= sizeof(struct efx_rss_context_priv),
 	.get_rxfh		= efx_ethtool_get_rxfh,
 	.set_rxfh		= efx_ethtool_set_rxfh,
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 55c9f613ab64..8c89dc33d51c 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -731,6 +731,9 @@  struct kernel_ethtool_ts_info {
  *	do not have to set this bit.
  * @cap_rss_sym_xor_supported: indicates if the driver supports symmetric-xor
  *	RSS.
+ * @rxfh_per_ctx_key: device supports setting different RSS key for each
+ *	additional context. Netlink API should report hfunc, key, and input_xfrm
+ *	for every context, not just context 0.
  * @rxfh_indir_space: max size of RSS indirection tables, if indirection table
  *	size as returned by @get_rxfh_indir_size may change during lifetime
  *	of the device. Leave as 0 if the table size is constant.
@@ -952,6 +955,7 @@  struct ethtool_ops {
 	u32     cap_link_lanes_supported:1;
 	u32     cap_rss_ctx_supported:1;
 	u32	cap_rss_sym_xor_supported:1;
+	u32	rxfh_per_ctx_key:1;
 	u32	rxfh_indir_space;
 	u16	rxfh_key_space;
 	u16	rxfh_priv_size;
diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index 52dfb07393a6..e32b791f8d1c 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -1261,10 +1261,15 @@  static noinline_for_stack int ethtool_get_rxfh(struct net_device *dev,
 		if (rxfh_dev.indir)
 			memcpy(rxfh_dev.indir, ethtool_rxfh_context_indir(ctx),
 			       indir_bytes);
-		if (rxfh_dev.key)
-			memcpy(rxfh_dev.key, ethtool_rxfh_context_key(ctx),
-			       user_key_size);
-		rxfh_dev.hfunc = ctx->hfunc;
+		if (!ops->rxfh_per_ctx_key) {
+			rxfh_dev.key_size = 0;
+		} else {
+			if (rxfh_dev.key)
+				memcpy(rxfh_dev.key,
+				       ethtool_rxfh_context_key(ctx),
+				       user_key_size);
+			rxfh_dev.hfunc = ctx->hfunc;
+		}
 		rxfh_dev.input_xfrm = ctx->input_xfrm;
 		ret = 0;
 	} else {
@@ -1281,6 +1286,11 @@  static noinline_for_stack int ethtool_get_rxfh(struct net_device *dev,
 				&rxfh_dev.input_xfrm,
 				sizeof(rxfh.input_xfrm))) {
 		ret = -EFAULT;
+	} else if (copy_to_user(useraddr +
+				offsetof(struct ethtool_rxfh, key_size),
+				&rxfh_dev.key_size,
+				sizeof(rxfh.key_size))) {
+		ret = -EFAULT;
 	} else if (copy_to_user(useraddr +
 			      offsetof(struct ethtool_rxfh, rss_config[0]),
 			      rss_config, total_size)) {
@@ -1386,6 +1396,13 @@  static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev,
 
 	indir_bytes = dev_indir_size * sizeof(rxfh_dev.indir[0]);
 
+	/* Check settings which may be global rather than per RSS-context */
+	if (rxfh.rss_context && !ops->rxfh_per_ctx_key)
+		if (rxfh.key_size ||
+		    (rxfh.hfunc && rxfh.hfunc != ETH_RSS_HASH_NO_CHANGE) ||
+		    (rxfh.input_xfrm && rxfh.input_xfrm != RXH_XFRM_NO_CHANGE))
+			return -EOPNOTSUPP;
+
 	rss_config = kzalloc(indir_bytes + dev_key_size, GFP_USER);
 	if (!rss_config)
 		return -ENOMEM;
diff --git a/net/ethtool/rss.c b/net/ethtool/rss.c
index a06bdac8b8a2..cd8100d81919 100644
--- a/net/ethtool/rss.c
+++ b/net/ethtool/rss.c
@@ -10,6 +10,7 @@  struct rss_req_info {
 
 struct rss_reply_data {
 	struct ethnl_reply_data		base;
+	bool				no_key_fields;
 	u32				indir_size;
 	u32				hkey_size;
 	u32				hfunc;
@@ -60,9 +61,12 @@  rss_prepare_data(const struct ethnl_req_info *req_base,
 		return -EOPNOTSUPP;
 
 	/* Some drivers don't handle rss_context */
-	if (request->rss_context && !(ops->cap_rss_ctx_supported ||
-				      ops->create_rxfh_context))
-		return -EOPNOTSUPP;
+	if (request->rss_context) {
+		if (!ops->cap_rss_ctx_supported && !ops->create_rxfh_context)
+			return -EOPNOTSUPP;
+
+		data->no_key_fields = !ops->rxfh_per_ctx_key;
+	}
 
 	ret = ethnl_ops_begin(dev);
 	if (ret < 0)
@@ -132,13 +136,18 @@  rss_fill_reply(struct sk_buff *skb, const struct ethnl_req_info *req_base,
 	    nla_put_u32(skb, ETHTOOL_A_RSS_CONTEXT, request->rss_context))
 		return -EMSGSIZE;
 
+	if ((data->indir_size &&
+	     nla_put(skb, ETHTOOL_A_RSS_INDIR,
+		     sizeof(u32) * data->indir_size, data->indir_table)))
+		return -EMSGSIZE;
+
+	if (data->no_key_fields)
+		return 0;
+
 	if ((data->hfunc &&
 	     nla_put_u32(skb, ETHTOOL_A_RSS_HFUNC, data->hfunc)) ||
 	    (data->input_xfrm &&
 	     nla_put_u32(skb, ETHTOOL_A_RSS_INPUT_XFRM, data->input_xfrm)) ||
-	    (data->indir_size &&
-	     nla_put(skb, ETHTOOL_A_RSS_INDIR,
-		     sizeof(u32) * data->indir_size, data->indir_table)) ||
 	    (data->hkey_size &&
 	     nla_put(skb, ETHTOOL_A_RSS_HKEY, data->hkey_size, data->hkey)))
 		return -EMSGSIZE;