bnx2x: Prevent restarting Tx during bnx2x_nic_unload
Tx queues were stopped before bp->state was changed to a value different
from BNX2X_STATE_OPEN, which allowed the bnx2x_tx_int() called from the
NAPI context to re-enable it. This then allowed the netdev->ndo_start_xmit()
to be called in the middle of the function reset and rings freeing.
This patch changes bp->state to a value different
from BNX2X_STATE_OPEN BEFORE disabling the Tx queues in order to restore the
broken protection against the above race in the bnx2x_tx_int().
Signed-off-by: Vladislav Zolotarov <vladz@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/bnx2x/bnx2x_cmn.c b/drivers/net/bnx2x/bnx2x_cmn.c
index 5b0dba6..d724a18 100644
--- a/drivers/net/bnx2x/bnx2x_cmn.c
+++ b/drivers/net/bnx2x/bnx2x_cmn.c
@@ -1989,14 +1989,20 @@
return -EINVAL;
}
+ /*
+ * It's important to set the bp->state to the value different from
+ * BNX2X_STATE_OPEN and only then stop the Tx. Otherwise bnx2x_tx_int()
+ * may restart the Tx from the NAPI context (see bnx2x_tx_int()).
+ */
+ bp->state = BNX2X_STATE_CLOSING_WAIT4_HALT;
+ smp_mb();
+
/* Stop Tx */
bnx2x_tx_disable(bp);
#ifdef BCM_CNIC
bnx2x_cnic_notify(bp, CNIC_CTL_STOP_CMD);
#endif
- bp->state = BNX2X_STATE_CLOSING_WAIT4_HALT;
- smp_mb();
bp->rx_mode = BNX2X_RX_MODE_NONE;