net/af_iucv: don't use paged skbs for TX on HiperSockets
authorJulian Wiedmann <jwi@linux.vnet.ibm.com>
Tue, 10 Jan 2017 16:10:34 +0000 (17:10 +0100)
committerDavid S. Miller <davem@davemloft.net>
Wed, 11 Jan 2017 02:08:29 +0000 (21:08 -0500)
commitdc5367bcc556e97555fc94a32cd1aadbebdff47e
tree78778f65fe742ff199468fc3ac00e572513b89bc
parent5d722b3024f6762addb8642ffddc9f275b5107ae
net/af_iucv: don't use paged skbs for TX on HiperSockets

With commit e53743994e21
("af_iucv: use paged SKBs for big outbound messages"),
we transmit paged skbs for both of AF_IUCV's transport modes
(IUCV or HiperSockets).
The qeth driver for Layer 3 HiperSockets currently doesn't
support NETIF_F_SG, so these skbs would just be linearized again
by the stack.
Avoid that overhead by using paged skbs only for IUCV transport.

cc stable, since this also circumvents a significant skb leak when
sending large messages (where the skb then needs to be linearized).

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> # v4.8+
Fixes: e53743994e21 ("af_iucv: use paged SKBs for big outbound messages")
Signed-off-by: David S. Miller <davem@davemloft.net>
net/iucv/af_iucv.c