ixgbe: fix setting of promisc mode when using mac-vlans

Introduce uc_set_promisc flag to fix enabling of promisc mode
when exceeding the number of supported RAR entries.

Issue discovered by Ben Greear when using mac-vlans.

Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ixgbe/ixgbe_common.c b/drivers/net/ixgbe/ixgbe_common.c
index 6eb5814..753f2ab 100644
--- a/drivers/net/ixgbe/ixgbe_common.c
+++ b/drivers/net/ixgbe/ixgbe_common.c
@@ -1392,14 +1392,17 @@
 			fctrl = IXGBE_READ_REG(hw, IXGBE_FCTRL);
 			fctrl |= IXGBE_FCTRL_UPE;
 			IXGBE_WRITE_REG(hw, IXGBE_FCTRL, fctrl);
+			hw->addr_ctrl.uc_set_promisc = true;
 		}
 	} else {
 		/* only disable if set by overflow, not by user */
-		if (old_promisc_setting && !hw->addr_ctrl.user_set_promisc) {
+		if ((old_promisc_setting && hw->addr_ctrl.uc_set_promisc) &&
+		   !(hw->addr_ctrl.user_set_promisc)) {
 			hw_dbg(hw, " Leaving address overflow promisc mode\n");
 			fctrl = IXGBE_READ_REG(hw, IXGBE_FCTRL);
 			fctrl &= ~IXGBE_FCTRL_UPE;
 			IXGBE_WRITE_REG(hw, IXGBE_FCTRL, fctrl);
+			hw->addr_ctrl.uc_set_promisc = false;
 		}
 	}