diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 4587a4c369232589fbbc77200ca3257440f850de..c77fa3529e15ffafe9a7e8d8ea3bbd2fc9517db6 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -163,6 +163,16 @@ extern int
 __ethtool_get_link_ksettings(struct net_device *dev,
 			     struct ethtool_link_ksettings *link_ksettings);
 
+/**
+ * ethtool_intersect_link_masks - Given two link masks, AND them together
+ * @dst: first mask and where result is stored
+ * @src: second mask to intersect with
+ *
+ * Given two link mode masks, AND them together and save the result in dst.
+ */
+void ethtool_intersect_link_masks(struct ethtool_link_ksettings *dst,
+				  struct ethtool_link_ksettings *src);
+
 void ethtool_convert_legacy_u32_to_link_mode(unsigned long *dst,
 					     u32 legacy_u32);
 
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 3228411ada0fa77e2796b733a695826282d82df9..0c406306792a5d211006e30ecdd7d5018b5f4462 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -403,6 +403,22 @@ static int __ethtool_set_flags(struct net_device *dev, u32 data)
 	return 0;
 }
 
+/* Given two link masks, AND them together and save the result in dst. */
+void ethtool_intersect_link_masks(struct ethtool_link_ksettings *dst,
+				  struct ethtool_link_ksettings *src)
+{
+	unsigned int size = BITS_TO_LONGS(__ETHTOOL_LINK_MODE_MASK_NBITS);
+	unsigned int idx = 0;
+
+	for (; idx < size; idx++) {
+		dst->link_modes.supported[idx] &=
+			src->link_modes.supported[idx];
+		dst->link_modes.advertising[idx] &=
+			src->link_modes.advertising[idx];
+	}
+}
+EXPORT_SYMBOL(ethtool_intersect_link_masks);
+
 void ethtool_convert_legacy_u32_to_link_mode(unsigned long *dst,
 					     u32 legacy_u32)
 {