diff -u linux-4.4.0/debian/changelog linux-4.4.0/debian/changelog
--- linux-4.4.0/debian/changelog
+++ linux-4.4.0/debian/changelog
@@ -1,3 +1,13 @@
+linux (4.4.0-22.40~ubuntu1) xenial; urgency=low
+
+  [ Ivan Suzdal]
+
+  * LP: #1582328
+    - e1000: Double Tx descriptors needed check for 82544
+    - e1000: Do not overestimate descriptor counts in Tx pre-check
+
+ -- Ivan Suzdal <isuzdal@mirantis.com>  Mon, 16 May 2016 16:44:54 +0000
+
 linux (4.4.0-22.40) xenial; urgency=low
 
   [ Kamal Mostafa ]
only in patch2:
unchanged:
--- linux-4.4.0.orig/.pc/.quilt_patches
+++ linux-4.4.0/.pc/.quilt_patches
@@ -0,0 +1 @@
+debian/patches
only in patch2:
unchanged:
--- linux-4.4.0.orig/.pc/.quilt_series
+++ linux-4.4.0/.pc/.quilt_series
@@ -0,0 +1 @@
+series
only in patch2:
unchanged:
--- linux-4.4.0.orig/.pc/.version
+++ linux-4.4.0/.pc/.version
@@ -0,0 +1 @@
+2
only in patch2:
unchanged:
--- linux-4.4.0.orig/debian/patches/0001-e1000-double-check-for-82544.patch
+++ linux-4.4.0/debian/patches/0001-e1000-double-check-for-82544.patch
@@ -0,0 +1,35 @@
+Index: linux-4.4.0/drivers/net/ethernet/intel/e1000/e1000_main.c
+===================================================================
+--- linux-4.4.0.orig/drivers/net/ethernet/intel/e1000/e1000_main.c
++++ linux-4.4.0/drivers/net/ethernet/intel/e1000/e1000_main.c
+@@ -3256,12 +3256,29 @@ static netdev_tx_t e1000_xmit_frame(stru
+ 			     nr_frags, mss);
+ 
+ 	if (count) {
++		/* The descriptors needed is higher than other Intel drivers
++		 * due to a number of workarounds.  The breakdown is below:
++		 * Data descriptors: MAX_SKB_FRAGS + 1
++		 * Context Descriptor: 1
++		 * Keep head from touching tail: 2
++		 * Workarounds: 3
++		 */
++		int desc_needed = MAX_SKB_FRAGS + 7;
++
+ 		netdev_sent_queue(netdev, skb->len);
+ 		skb_tx_timestamp(skb);
+ 
+ 		e1000_tx_queue(adapter, tx_ring, tx_flags, count);
++
++		/* 82544 potentially requires twice as many data descriptors
++		 * in order to guarantee buffers don't end on evenly-aligned
++		 * dwords
++		 */
++		if (adapter->pcix_82544)
++			desc_needed += MAX_SKB_FRAGS + 1;
++
+ 		/* Make sure there is space in the ring for the next send. */
+-		e1000_maybe_stop_tx(netdev, tx_ring, MAX_SKB_FRAGS + 2);
++		e1000_maybe_stop_tx(netdev, tx_ring, desc_needed);
+ 
+ 		if (!skb->xmit_more ||
+ 		    netif_xmit_stopped(netdev_get_tx_queue(netdev, 0))) {
only in patch2:
unchanged:
--- linux-4.4.0.orig/debian/patches/0002-e1000-do-not-overestimate-descriptor-counts-in-Tx-pre-check.patch
+++ linux-4.4.0/debian/patches/0002-e1000-do-not-overestimate-descriptor-counts-in-Tx-pre-check.patch
@@ -0,0 +1,13 @@
+Index: linux-4.4.0/drivers/net/ethernet/intel/e1000/e1000_main.c
+===================================================================
+--- linux-4.4.0.orig/drivers/net/ethernet/intel/e1000/e1000_main.c
++++ linux-4.4.0/drivers/net/ethernet/intel/e1000/e1000_main.c
+@@ -3106,7 +3106,7 @@ static int e1000_maybe_stop_tx(struct ne
+ 	return __e1000_maybe_stop_tx(netdev, size);
+ }
+ 
+-#define TXD_USE_COUNT(S, X) (((S) >> (X)) + 1)
++#define TXD_USE_COUNT(S, X) (((S) + ((1 << (X)) - 1)) >> (X))
+ static netdev_tx_t e1000_xmit_frame(struct sk_buff *skb,
+ 				    struct net_device *netdev)
+ {
only in patch2:
unchanged:
--- linux-4.4.0.orig/debian/patches/series
+++ linux-4.4.0/debian/patches/series
@@ -0,0 +1,2 @@
+0001-e1000-double-check-for-82544.patch
+0002-e1000-do-not-overestimate-descriptor-counts-in-Tx-pre-check.patch