Hello Florian Fainelli,
The patch 80f8dea8767e: "net: systemport: Restore Broadcom tag match
filters upon resume" from Nov 6, 2018, leads to the following static
checker warning:
drivers/net/ethernet/broadcom/bcmsysport.c:2202 bcm_sysport_rule_set()
warn: array off by one? 'priv->filters_loc[index]'
drivers/net/ethernet/broadcom/bcmsysport.c
2168 static int bcm_sysport_rule_set(struct bcm_sysport_priv *priv,
2169 struct ethtool_rxnfc *nfc)
2170 {
2171 unsigned int index;
2172 u32 reg;
2173
2174 /* We cannot match locations greater than what the classification ID
2175 * permits (256 entries)
2176 */
2177 if (nfc->fs.location > RXCHK_BRCM_TAG_CID_MASK)
2178 return -E2BIG;
2179
2180 /* We cannot support flows that are not destined for a wake-up */
2181 if (nfc->fs.ring_cookie != RX_CLS_FLOW_WAKE)
2182 return -EOPNOTSUPP;
2183
2184 /* All filters are already in use, we cannot match more rules */
2185 if (bitmap_weight(priv->filters, RXCHK_BRCM_TAG_MAX) ==
2186 RXCHK_BRCM_TAG_MAX)
2187 return -ENOSPC;
^^^^^^^^^^^^^^
This check means we have space.
2188
2189 index = find_first_zero_bit(priv->filters, RXCHK_BRCM_TAG_MAX);
2190 if (index > RXCHK_BRCM_TAG_MAX)
^^^^^^^^^^^^^^^^^^^^^^^^^^
This check is off by one, but it's not required. You could fix it or
delete it?
2191 return -ENOSPC;
2192
2193 /* Location is the classification ID, and index is the position
2194 * within one of our 8 possible filters to be programmed
2195 */
2196 reg = rxchk_readl(priv, RXCHK_BRCM_TAG(index));
2197 reg &= ~(RXCHK_BRCM_TAG_CID_MASK << RXCHK_BRCM_TAG_CID_SHIFT);
2198 reg |= nfc->fs.location << RXCHK_BRCM_TAG_CID_SHIFT;
2199 rxchk_writel(priv, reg, RXCHK_BRCM_TAG(index));
2200 rxchk_writel(priv, 0xff00ffff, RXCHK_BRCM_TAG_MASK(index));
2201
2202 priv->filters_loc[index] = nfc->fs.location;
^^^^^
2203 set_bit(index, priv->filters);
^^^^^
Off by one.
2204
2205 return 0;
2206 }
regards,
dan carpenter
