From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Mon, 29 Jun 2009 12:06:41 +0800

On Mon, Jun 29, 2009 at 12:03:30PM +0800, Herbert Xu wrote:

quoted

tcp: Stop non-TSO packets morphing into TSO

Here's a follow-up patch to optimise this boundary case.

tcp: Do not tack on TSO data to non-TSO packet

If a socket starts out on a non-TSO route, and then switches to
a TSO route, then we will tack on data to the tail of the tx queue
even if it started out life as non-TSO.  This is suboptimal because
all of it will then be copied and checksummed unnecessarily.

This patch fixes this by ensuring that skb->ip_summed is set to
CHECKSUM_PARTIAL before appending extra data beyond the MSS.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Applied.