tree 1b4d10e614534a14be24c3ddbb54cef0118ad1ea
parent 0ee3341eb34eb1a6b1106df95ebd0bc8b394a7f7
author Jason Wang <jasowang@redhat.com> 1560763254 -0400
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1564904000 +0200

vhost_net: disable zerocopy by default

[ Upstream commit 098eadce3c622c07b328d0a43dda379b38cf7c5e ]

Vhost_net was known to suffer from HOL[1] issues which is not easy to
fix. Several downstream disable the feature by default. What's more,
the datapath was split and datacopy path got the support of batching
and XDP support recently which makes it faster than zerocopy part for
small packets transmission.

It looks to me that disable zerocopy by default is more
appropriate. It cold be enabled by default again in the future if we
fix the above issues.

[1] https://patchwork.kernel.org/patch/3787671/

Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>