From: Hans-Joachim Picht <hpicht@redhat.com>
Date: Tue, 14 Jul 2009 14:03:32 +0200
Subject: [s390] qeth: improve no_checksumming handling for layer3
Message-id: 20090714120332.GA26518@redhat.com
O-Subject: [RHEL5 U5 PATCH 1/1] s390 - qeth: improve no_checksumming handling for layer3
Bugzilla: 503238
RH-Acked-by: Jiri Olsa <jolsa@redhat.com>
RH-Acked-by: Pete Zaitcev <zaitcev@redhat.com>

Description
============

Problem: If sysfs-attribute checksumming is set to
"no-checksumming" for a layer3 qeth device, incoming
data is stored in skbs with incorrect setting of
skb->ip_summed.

Solution: Set skb->ip_summed to CHECKSUM_UNNECESSARY if
RX-checksumming is not required.

Bugzilla
=========

BZ 503238
https://bugzilla.redhat.com/show_bug.cgi?id=503238

Upstream status of the patch:
=============================

Patch is upstream as of commit b91398008cae916c528d907f5d7a9ed54f35b4e9

Test status:
============

The patch has been tested and fixes the problem.
The fix has been verified by the IBM test department.

Please ACK.

With best regards,

	--Hans

diff --git a/drivers/s390/net/qeth_main.c b/drivers/s390/net/qeth_main.c
index 16109c1..d11ea35 100644
--- a/drivers/s390/net/qeth_main.c
+++ b/drivers/s390/net/qeth_main.c
@@ -2628,16 +2628,22 @@ qeth_rebuild_skb(struct qeth_card *card, struct sk_buff *skb,
 		qeth_rebuild_skb_fake_ll(card, skb, hdr);
 	else
 		skb->mac.raw = skb->data;
-	skb->ip_summed = card->options.checksum_type;
-	if (card->options.checksum_type == HW_CHECKSUMMING){
-		if ( (hdr->hdr.l3.ext_flags &
-		      (QETH_HDR_EXT_CSUM_HDR_REQ |
-		       QETH_HDR_EXT_CSUM_TRANSP_REQ)) ==
-		     (QETH_HDR_EXT_CSUM_HDR_REQ |
-		      QETH_HDR_EXT_CSUM_TRANSP_REQ) )
+	switch (card->options.checksum_type) {
+	case SW_CHECKSUMMING:
+		skb->ip_summed = CHECKSUM_NONE;
+		break;
+	case NO_CHECKSUMMING:
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+		break;
+	case HW_CHECKSUMMING:
+		if ((hdr->hdr.l3.ext_flags &
+		    (QETH_HDR_EXT_CSUM_HDR_REQ |
+		     QETH_HDR_EXT_CSUM_TRANSP_REQ)) ==
+		    (QETH_HDR_EXT_CSUM_HDR_REQ |
+		     QETH_HDR_EXT_CSUM_TRANSP_REQ))
 			skb->ip_summed = CHECKSUM_UNNECESSARY;
 		else
-			skb->ip_summed = SW_CHECKSUMMING;
+			skb->ip_summed = CHECKSUM_NONE;
 	}
 	return vlan_id;
 }