Re: [net-next PATCH v0 3/6] net: netcp: Fixes error in oversized memory allocation for statistics storage

The CPSW driver keeps internally some, but not all, of
the statistics available in the hw statistics modules.  Furthermore,
some of the locations in the hw statistics modules are reserved and
contain no useful information.  Prior to this patch, the driver
allocates memory of the size of the the whole hw statistics modules,
instead of the size of statistics-entries-interested-in (i.e. et_stats),
for internal storage.  This patch fixes that.

Signed-off-by: WingMan Kwok <redacted>
---
  drivers/net/ethernet/ti/netcp_ethss.c |   42 ++++++++++++++++-----------------
  1 file changed, 21 insertions(+), 21 deletions(-)

diff --git a/drivers/net/ethernet/ti/netcp_ethss.c b/drivers/net/ethernet/ti/netcp_ethss.c
index b954856..a1f16e1 100644
--- a/drivers/net/ethernet/ti/netcp_ethss.c
+++ b/drivers/net/ethernet/ti/netcp_ethss.c

@@ -2555,10 +2555,12 @@ static int set_xgbe_ethss10_priv(struct gbe_priv *gbe_dev,
  	}
  	gbe_dev->xgbe_serdes_regs = regs;

+	gbe_dev->et_stats = xgbe10_et_stats;
+	gbe_dev->num_et_stats = ARRAY_SIZE(xgbe10_et_stats);
+
  	gbe_dev->hw_stats = devm_kzalloc(gbe_dev->dev,
-				  XGBE10_NUM_STAT_ENTRIES *
-				  (gbe_dev->max_num_ports) * sizeof(u64),
-	

+					 gbe_dev->num_et_stats * sizeof(u64),
+					 GFP_KERNEL);
  	if (!gbe_dev->hw_stats) {
  		dev_err(gbe_dev->dev, "hw_stats memory allocation failed\n");
  		return -ENOMEM;

@@ -2577,8 +2579,6 @@ static int set_xgbe_ethss10_priv(struct gbe_priv *gbe_dev,
  	gbe_dev->ale_ports = gbe_dev->max_num_ports;
  	gbe_dev->host_port = XGBE10_HOST_PORT_NUM;
  	gbe_dev->ale_entries = XGBE10_NUM_ALE_ENTRIES;
-	gbe_dev->et_stats = xgbe10_et_stats;
-	gbe_dev->num_et_stats = ARRAY_SIZE(xgbe10_et_stats);
  	gbe_dev->stats_en_mask = (1 << (gbe_dev->max_num_ports)) - 1;

  	/* Subsystem registers */

@@ -2663,10 +2663,12 @@ static int set_gbe_ethss14_priv(struct gbe_priv *gbe_dev,
  	}
  	gbe_dev->switch_regs = regs;

+	gbe_dev->et_stats = gbe13_et_stats;
+	gbe_dev->num_et_stats = ARRAY_SIZE(gbe13_et_stats);
+
  	gbe_dev->hw_stats = devm_kzalloc(gbe_dev->dev,
-					  GBE13_NUM_HW_STAT_ENTRIES *
-					  gbe_dev->max_num_slaves * sizeof(u64),
-					  GFP_KERNEL);
+					 gbe_dev->num_et_stats * sizeof(u64),
+					 GFP_KERNEL);
  	if (!gbe_dev->hw_stats) {
  		dev_err(gbe_dev->dev, "hw_stats memory allocation failed\n");
  		return -ENOMEM;

@@ -2689,8 +2691,6 @@ static int set_gbe_ethss14_priv(struct gbe_priv *gbe_dev,
  	gbe_dev->ale_ports = gbe_dev->max_num_ports;
  	gbe_dev->host_port = GBE13_HOST_PORT_NUM;
  	gbe_dev->ale_entries = GBE13_NUM_ALE_ENTRIES;
-	gbe_dev->et_stats = gbe13_et_stats;
-	gbe_dev->num_et_stats = ARRAY_SIZE(gbe13_et_stats);
  	gbe_dev->stats_en_mask = GBE13_REG_VAL_STAT_ENABLE_ALL;

  	/* Subsystem registers */

@@ -2717,10 +2717,18 @@ static int set_gbenu_ethss_priv(struct gbe_priv *gbe_dev,
  	void __iomem *regs;
  	int i, ret;

+	gbe_dev->et_stats = gbenu_et_stats;
+
+	if (IS_SS_ID_NU(gbe_dev))
+		gbe_dev->num_et_stats = GBENU_ET_STATS_HOST_SIZE +
+			(gbe_dev->max_num_slaves * GBENU_ET_STATS_PORT_SIZE);
+	else
+		gbe_dev->num_et_stats = GBENU_ET_STATS_HOST_SIZE +
+					GBENU_ET_STATS_PORT_SIZE;
+
  	gbe_dev->hw_stats = devm_kzalloc(gbe_dev->dev,
-				  GBENU_NUM_HW_STAT_ENTRIES *
-				  (gbe_dev->max_num_ports) * sizeof(u64),
-				  GFP_KERNEL);
+					 gbe_dev->num_et_stats * sizeof(u64),
+					 GFP_KERNEL);
  	if (!gbe_dev->hw_stats) {
  		dev_err(gbe_dev->dev, "hw_stats memory allocation failed\n");
  		return -ENOMEM;

@@ -2753,16 +2761,8 @@ static int set_gbenu_ethss_priv(struct gbe_priv *gbe_dev,
  	gbe_dev->ale_ports = gbe_dev->max_num_ports;
  	gbe_dev->host_port = GBENU_HOST_PORT_NUM;
  	gbe_dev->ale_entries = GBE13_NUM_ALE_ENTRIES;
-	gbe_dev->et_stats = gbenu_et_stats;
  	gbe_dev->stats_en_mask = (1 << (gbe_dev->max_num_ports)) - 1;

-	if (IS_SS_ID_NU(gbe_dev))
-		gbe_dev->num_et_stats = GBENU_ET_STATS_HOST_SIZE +
-			(gbe_dev->max_num_slaves * GBENU_ET_STATS_PORT_SIZE);
-	else
-		gbe_dev->num_et_stats = GBENU_ET_STATS_HOST_SIZE +
-					GBENU_ET_STATS_PORT_SIZE;
-
  	/* Subsystem registers */
  	GBENU_SET_REG_OFS(gbe_dev, ss_regs, id_ver);