4.7-stable review patch.  If anyone has any objections, please let me know.


From: Artem Germanov <agerma...@anchorfree.com>

[ Upstream commit db7196a0d0984b933ccf2cd6a60e26abf466e8a3 ]

Commit 76174004a0f19785a328f40388e87e982bbf69b9
(tcp: do not slow start when cwnd equals ssthresh )
introduced regression in TCP YeAH. Using 100ms delay 1% loss virtual
ethernet link kernel 4.2 shows bandwidth ~500KB/s for single TCP
connection and kernel 4.3 and above (including 4.8-rc4) shows bandwidth
   That is caused by stalled cwnd when cwnd equals ssthresh. This patch
fixes it by proper increasing cwnd in this case.

Signed-off-by: Artem Germanov <agerma...@anchorfree.com>
Acked-by: Dmitry Adamushko <d.adamus...@anchorfree.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
 net/ipv4/tcp_yeah.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/ipv4/tcp_yeah.c
+++ b/net/ipv4/tcp_yeah.c
@@ -76,7 +76,7 @@ static void tcp_yeah_cong_avoid(struct s
        if (!tcp_is_cwnd_limited(sk))
-       if (tp->snd_cwnd <= tp->snd_ssthresh)
+       if (tcp_in_slow_start(tp))
                tcp_slow_start(tp, acked);
        else if (!yeah->doing_reno_now) {

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