[PATCH net 4/6] bnxt_en: Pass correct extended TX port statistics size to firmware.

[Michael Chan]

If driver determines that extended TX port statistics are not supported
or allocation of the data structure fails, make sure to pass 0 TX stats
size to firmware to disable it.  The firmware returned TX stats size should
also be set to 0 for consistency.  This will prevent
bnxt_get_ethtool_stats() from accessing the NULL TX stats pointer in
case there is mismatch between firmware and driver.

Fixes: 36e53349b60b ("bnxt_en: Add additional extended port statistics.")
Signed-off-by: Michael Chan <michael.c...@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c 
b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index b03669f..a9172b2 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -6753,6 +6753,7 @@ static int bnxt_hwrm_port_qstats_ext(struct bnxt *bp)
        struct hwrm_queue_pri2cos_qcfg_input req2 = {0};
        struct hwrm_port_qstats_ext_input req = {0};
        struct bnxt_pf_info *pf = &bp->pf;
+       u32 tx_stat_size;
        int rc;
 
        if (!(bp->flags & BNXT_FLAG_PORT_STATS_EXT))
@@ -6762,13 +6763,16 @@ static int bnxt_hwrm_port_qstats_ext(struct bnxt *bp)
        req.port_id = cpu_to_le16(pf->port_id);
        req.rx_stat_size = cpu_to_le16(sizeof(struct rx_port_stats_ext));
        req.rx_stat_host_addr = cpu_to_le64(bp->hw_rx_port_stats_ext_map);
-       req.tx_stat_size = cpu_to_le16(sizeof(struct tx_port_stats_ext));
+       tx_stat_size = bp->hw_tx_port_stats_ext ?
+                      sizeof(*bp->hw_tx_port_stats_ext) : 0;
+       req.tx_stat_size = cpu_to_le16(tx_stat_size);
        req.tx_stat_host_addr = cpu_to_le64(bp->hw_tx_port_stats_ext_map);
        mutex_lock(&bp->hwrm_cmd_lock);
        rc = _hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
        if (!rc) {
                bp->fw_rx_stats_ext_size = le16_to_cpu(resp->rx_stat_size) / 8;
-               bp->fw_tx_stats_ext_size = le16_to_cpu(resp->tx_stat_size) / 8;
+               bp->fw_tx_stats_ext_size = tx_stat_size ?
+                       le16_to_cpu(resp->tx_stat_size) / 8 : 0;
        } else {
                bp->fw_rx_stats_ext_size = 0;
                bp->fw_tx_stats_ext_size = 0;
-- 
2.5.1