ixgbe: fix bit masking in queue stop

The masking for the RX/TX enable bit was incorrect in the rx and tx
queue stop functions. Instead of using "& MASK" it used "| MASK" which
would always return true. This error was found by converity scan.

CID 13215 : Wrong operator used (CONSTANT_EXPRESSION_RESULT)
operator_confusion: txdctl | 33554432 is always 1/true regardless of the
values of its operand. This occurs as the logical second operand of
'&&'.

CID 13216 : Wrong operator used (CONSTANT_EXPRESSION_RESULT)
operator_confusion: rxdctl | 33554432 is always 1/true regardless of the
values of its operand. This occurs as the logical second operand of
'&&'.

Coverity issue: 13215
Coverity issue: 13216
Fixes: 029fd06d40fa ("ixgbe: queue start and stop")

Signed-off-by: Piotr Azarewicz <piotrx.t.azarewicz@intel.com>
Acked-by: Wenzhuo Lu <wenzhuo.lu@intel.com>

diff --git a/drivers/net/ixgbe/ixgbe_rxtx.c b/drivers/net/ixgbe/ixgbe_rxtx.c
index 35673fc..ceaf4ab 100644 (file)
--- a/drivers/net/ixgbe/ixgbe_rxtx.c
+++ b/drivers/net/ixgbe/ixgbe_rxtx.c
@@ -4817,12 +4817,12 @@ ixgbe_dev_rx_queue_stop(struct rte_eth_dev *dev, uint16_t rx_queue_id)
                rxdctl &= ~IXGBE_RXDCTL_ENABLE;
                IXGBE_WRITE_REG(hw, IXGBE_RXDCTL(rxq->reg_idx), rxdctl);
 
-               /* Wait until RX Enable ready */
+               /* Wait until RX Enable bit clear */
                poll_ms = RTE_IXGBE_REGISTER_POLL_WAIT_10_MS;
                do {
                        rte_delay_ms(1);
                        rxdctl = IXGBE_READ_REG(hw, IXGBE_RXDCTL(rxq->reg_idx));
-               } while (--poll_ms && (rxdctl | IXGBE_RXDCTL_ENABLE));
+               } while (--poll_ms && (rxdctl & IXGBE_RXDCTL_ENABLE));
                if (!poll_ms)
                        PMD_INIT_LOG(ERR, "Could not disable Rx Queue %d",
                                     rx_queue_id);
@@ -4920,14 +4920,14 @@ ixgbe_dev_tx_queue_stop(struct rte_eth_dev *dev, uint16_t tx_queue_id)
        txdctl &= ~IXGBE_TXDCTL_ENABLE;
        IXGBE_WRITE_REG(hw, IXGBE_TXDCTL(txq->reg_idx), txdctl);
 
-       /* Wait until TX Enable ready */
+       /* Wait until TX Enable bit clear */
        if (hw->mac.type == ixgbe_mac_82599EB) {
                poll_ms = RTE_IXGBE_REGISTER_POLL_WAIT_10_MS;
                do {
                        rte_delay_ms(1);
                        txdctl = IXGBE_READ_REG(hw,
                                                IXGBE_TXDCTL(txq->reg_idx));
-               } while (--poll_ms && (txdctl | IXGBE_TXDCTL_ENABLE));
+               } while (--poll_ms && (txdctl & IXGBE_TXDCTL_ENABLE));
                if (!poll_ms)
                        PMD_INIT_LOG(ERR, "Could not disable "
                                     "Tx Queue %d", tx_queue_id);