lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Mon, 3 Oct 2016 08:31:07 +0100
From:   Paul Durrant <paul.durrant@...rix.com>
To:     <netdev@...r.kernel.org>, <xen-devel@...ts.xenproject.org>
CC:     Paul Durrant <paul.durrant@...rix.com>,
        Wei Liu <wei.liu2@...rix.com>
Subject: [PATCH net-next 2/7] xen-netback: retire guest rx side prefix GSO feature

As far as I am aware only very old Windows network frontends make use of
this style of passing GSO packets from backend to frontend. These
frontends can easily be replaced by the freely available Xen Project
Windows PV network frontend, which uses the 'default' mechanism for
passing GSO packets, which is also used by all Linux frontends.

NOTE: Removal of this feature will not cause breakage in old Windows
      frontends. They simply will no longer receive GSO packets - the
      packets instead being fragmented in the backend.

Signed-off-by: Paul Durrant <paul.durrant@...rix.com>
---
Cc: Wei Liu <wei.liu2@...rix.com>
---
 drivers/net/xen-netback/common.h    |  1 -
 drivers/net/xen-netback/interface.c |  4 ++--
 drivers/net/xen-netback/rx.c        | 26 --------------------------
 drivers/net/xen-netback/xenbus.c    | 21 ---------------------
 4 files changed, 2 insertions(+), 50 deletions(-)

diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h
index 3a56268..e16004a 100644
--- a/drivers/net/xen-netback/common.h
+++ b/drivers/net/xen-netback/common.h
@@ -260,7 +260,6 @@ struct xenvif {
 
 	/* Frontend feature information. */
 	int gso_mask;
-	int gso_prefix_mask;
 
 	u8 can_sg:1;
 	u8 ip_csum:1;
diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c
index 83deeeb..1a009e7 100644
--- a/drivers/net/xen-netback/interface.c
+++ b/drivers/net/xen-netback/interface.c
@@ -328,9 +328,9 @@ static netdev_features_t xenvif_fix_features(struct net_device *dev,
 
 	if (!vif->can_sg)
 		features &= ~NETIF_F_SG;
-	if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV4))
+	if (~(vif->gso_mask) & GSO_BIT(TCPV4))
 		features &= ~NETIF_F_TSO;
-	if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV6))
+	if (~(vif->gso_mask) & GSO_BIT(TCPV6))
 		features &= ~NETIF_F_TSO6;
 	if (!vif->ip_csum)
 		features &= ~NETIF_F_IP_CSUM;
diff --git a/drivers/net/xen-netback/rx.c b/drivers/net/xen-netback/rx.c
index 03836aa..6bd7d6e 100644
--- a/drivers/net/xen-netback/rx.c
+++ b/drivers/net/xen-netback/rx.c
@@ -347,16 +347,6 @@ static int xenvif_gop_skb(struct sk_buff *skb,
 			gso_type = XEN_NETIF_GSO_TYPE_TCPV6;
 	}
 
-	/* Set up a GSO prefix descriptor, if necessary */
-	if ((1 << gso_type) & vif->gso_prefix_mask) {
-		RING_COPY_REQUEST(&queue->rx, queue->rx.req_cons++, &req);
-		meta = npo->meta + npo->meta_prod++;
-		meta->gso_type = gso_type;
-		meta->gso_size = skb_shinfo(skb)->gso_size;
-		meta->size = 0;
-		meta->id = req.id;
-	}
-
 	RING_COPY_REQUEST(&queue->rx, queue->rx.req_cons++, &req);
 	meta = npo->meta + npo->meta_prod++;
 
@@ -511,22 +501,6 @@ static void xenvif_rx_action(struct xenvif_queue *queue)
 	while ((skb = __skb_dequeue(&rxq)) != NULL) {
 		struct xen_netif_extra_info *extra = NULL;
 
-		if ((1 << queue->meta[npo.meta_cons].gso_type) &
-		    vif->gso_prefix_mask) {
-			resp = RING_GET_RESPONSE(&queue->rx,
-						 queue->rx.rsp_prod_pvt++);
-
-			resp->flags = XEN_NETRXF_gso_prefix |
-				      XEN_NETRXF_more_data;
-
-			resp->offset = queue->meta[npo.meta_cons].gso_size;
-			resp->id = queue->meta[npo.meta_cons].id;
-			resp->status = XENVIF_RX_CB(skb)->meta_slots_used;
-
-			npo.meta_cons++;
-			XENVIF_RX_CB(skb)->meta_slots_used--;
-		}
-
 		queue->stats.tx_bytes += skb->len;
 		queue->stats.tx_packets++;
 
diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index bacf6e0..6c57b02 100644
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c
@@ -1154,7 +1154,6 @@ static int read_xenbus_vif_flags(struct backend_info *be)
 	vif->can_sg = !!val;
 
 	vif->gso_mask = 0;
-	vif->gso_prefix_mask = 0;
 
 	if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv4",
 			 "%d", &val) < 0)
@@ -1162,32 +1161,12 @@ static int read_xenbus_vif_flags(struct backend_info *be)
 	if (val)
 		vif->gso_mask |= GSO_BIT(TCPV4);
 
-	if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv4-prefix",
-			 "%d", &val) < 0)
-		val = 0;
-	if (val)
-		vif->gso_prefix_mask |= GSO_BIT(TCPV4);
-
 	if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv6",
 			 "%d", &val) < 0)
 		val = 0;
 	if (val)
 		vif->gso_mask |= GSO_BIT(TCPV6);
 
-	if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv6-prefix",
-			 "%d", &val) < 0)
-		val = 0;
-	if (val)
-		vif->gso_prefix_mask |= GSO_BIT(TCPV6);
-
-	if (vif->gso_mask & vif->gso_prefix_mask) {
-		xenbus_dev_fatal(dev, err,
-				 "%s: gso and gso prefix flags are not "
-				 "mutually exclusive",
-				 dev->otherend);
-		return -EOPNOTSUPP;
-	}
-
 	if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-no-csum-offload",
 			 "%d", &val) < 0)
 		val = 0;
-- 
2.1.4

Powered by blists - more mailing lists