This is a note to let you know that I've just added the patch titled

    xen-netfront: Remove BUGs on paged skb data which crosses a page boundary

to the 3.10-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     
xen-netfront-remove-bugs-on-paged-skb-data-which-crosses-a-page-boundary.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 8d609725d4357f499e2103e46011308b32f53513 Mon Sep 17 00:00:00 2001
From: Seth Forshee <[email protected]>
Date: Tue, 25 Nov 2014 20:28:24 -0600
Subject: xen-netfront: Remove BUGs on paged skb data which crosses a page 
boundary

From: Seth Forshee <[email protected]>

commit 8d609725d4357f499e2103e46011308b32f53513 upstream.

These BUGs can be erroneously triggered by frags which refer to
tail pages within a compound page. The data in these pages may
overrun the hardware page while still being contained within the
compound page, but since compound_order() evaluates to 0 for tail
pages the assertion fails. The code already iterates through
subsequent pages correctly in this scenario, so the BUGs are
unnecessary and can be removed.

Fixes: f36c374782e4 ("xen/netfront: handle compound page fragments on transmit")
Signed-off-by: Seth Forshee <[email protected]>
Reviewed-by: David Vrabel <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/net/xen-netfront.c |    5 -----
 1 file changed, 5 deletions(-)

--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -459,9 +459,6 @@ static void xennet_make_frags(struct sk_
                len = skb_frag_size(frag);
                offset = frag->page_offset;
 
-               /* Data must not cross a page boundary. */
-               BUG_ON(len + offset > PAGE_SIZE<<compound_order(page));
-
                /* Skip unused frames from start of page */
                page += offset >> PAGE_SHIFT;
                offset &= ~PAGE_MASK;
@@ -469,8 +466,6 @@ static void xennet_make_frags(struct sk_
                while (len > 0) {
                        unsigned long bytes;
 
-                       BUG_ON(offset >= PAGE_SIZE);
-
                        bytes = PAGE_SIZE - offset;
                        if (bytes > len)
                                bytes = len;


Patches currently in stable-queue which might be from 
[email protected] are

queue-3.10/xen-netfront-remove-bugs-on-paged-skb-data-which-crosses-a-page-boundary.patch
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