Correct the multicast handling in the E1000 drivers as was

done in ixgbe, thanks to Mike Karels for this fix. When exiting
promiscuous mode MPE bit was being unconditionally cleared, this
should not be done if we are in MAX multicast groups.

1 files changed, 29 insertions, 4 deletions

diff --git a/sys/dev/e1000/if_em.c b/sys/dev/e1000/if_em.c
index 64be42d..12d8834 100644
--- a/sys/dev/e1000/if_em.c
+++ b/sys/dev/e1000/if_em.c
@@ -94,7 +94,7 @@ int	em_display_debug_stats = 0;
 /*********************************************************************
  *  Driver version:
  *********************************************************************/
-char em_driver_version[] = "7.3.7";
+char em_driver_version[] = "7.3.8";
 
 /*********************************************************************
  *  PCI Device ID Table
@@ -2133,12 +2133,37 @@ em_set_promisc(struct adapter *adapter)
 static void
 em_disable_promisc(struct adapter *adapter)
 {
-	u32	reg_rctl;
+	struct ifnet	*ifp = adapter->ifp;
+	u32		reg_rctl;
+	int		mcnt = 0;
 
 	reg_rctl = E1000_READ_REG(&adapter->hw, E1000_RCTL);
-
 	reg_rctl &=  (~E1000_RCTL_UPE);
-	reg_rctl &=  (~E1000_RCTL_MPE);
+	if (ifp->if_flags & IFF_ALLMULTI)
+		mcnt = MAX_NUM_MULTICAST_ADDRESSES;
+	else {
+		struct  ifmultiaddr *ifma;
+#if __FreeBSD_version < 800000
+		IF_ADDR_LOCK(ifp);
+#else   
+		if_maddr_rlock(ifp);
+#endif
+		TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
+			if (ifma->ifma_addr->sa_family != AF_LINK)
+				continue;
+			if (mcnt == MAX_NUM_MULTICAST_ADDRESSES)
+				break;
+			mcnt++;
+		}
+#if __FreeBSD_version < 800000
+		IF_ADDR_UNLOCK(ifp);
+#else
+		if_maddr_runlock(ifp);
+#endif
+	}
+	/* Don't disable if in MAX groups */
+	if (mcnt < MAX_NUM_MULTICAST_ADDRESSES)
+		reg_rctl &=  (~E1000_RCTL_MPE);
 	reg_rctl &=  (~E1000_RCTL_SBP);
 	E1000_WRITE_REG(&adapter->hw, E1000_RCTL, reg_rctl);
 }