[ Upstream commit a0dced17ad9dc08b1b25e0065b54c97a318e6e8b ]

This reverts commit 71130f29979c7c7956b040673e6b9d5643003176.

In commit 71130f29979c ("vxlan: fix tos value before xmit") we want to
make sure the tos value are filtered by RT_TOS() based on RFC1349.

       0     1     2     3     4     5     6     7
    +-----+-----+-----+-----+-----+-----+-----+-----+
    |   PRECEDENCE    |          TOS          | MBZ |
    +-----+-----+-----+-----+-----+-----+-----+-----+

But RFC1349 has been obsoleted by RFC2474. The new DSCP field defined like

       0     1     2     3     4     5     6     7
    +-----+-----+-----+-----+-----+-----+-----+-----+
    |          DS FIELD, DSCP           | ECN FIELD |
    +-----+-----+-----+-----+-----+-----+-----+-----+

So with

IPTOS_TOS_MASK          0x1E
RT_TOS(tos)		((tos)&IPTOS_TOS_MASK)

the first 3 bits DSCP info will get lost.

To take all the DSCP info in xmit, we should revert the patch and just push
all tos bits to ip_tunnel_ecn_encap(), which will handling ECN field later.

Fixes: 71130f29979c ("vxlan: fix tos value before xmit")
Signed-off-by: NHangbin Liu <liuhangbin@gmail.com>
Acked-by: NGuillaume Nault <gnault@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>