From: "Michael S. Tsirkin" <mst@redhat.com>
To: Jarod Wilson <jarod@redhat.com>
Cc: "VMware, Inc." <pv-drivers@vmware.com>,
netdev@vger.kernel.org, Haiyang Zhang <haiyangz@microsoft.com>,
linux-kernel@vger.kernel.org,
virtualization@lists.linux-foundation.org,
Shrikrishna Khare <skhare@vmware.com>
Subject: Re: [PATCH net-next 5/6] net: use core MTU range checking in virt drivers
Date: Wed, 19 Oct 2016 17:03:43 +0300 [thread overview]
Message-ID: <20161019170330-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <20161019165629-mutt-send-email-mst@kernel.org>
On Wed, Oct 19, 2016 at 04:59:46PM +0300, Michael S. Tsirkin wrote:
> On Tue, Oct 18, 2016 at 10:33:32PM -0400, Jarod Wilson wrote:
> > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > index fad84f3..4885a42 100644
> > --- a/drivers/net/virtio_net.c
> > +++ b/drivers/net/virtio_net.c
> > @@ -1419,17 +1419,6 @@ static const struct ethtool_ops virtnet_ethtool_ops = {
> > .set_settings = virtnet_set_settings,
> > };
> >
> > -#define MIN_MTU 68
> > -#define MAX_MTU 65535
> > -
> > -static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
> > -{
> > - if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
> > - return -EINVAL;
> > - dev->mtu = new_mtu;
> > - return 0;
> > -}
> > -
> > static const struct net_device_ops virtnet_netdev = {
> > .ndo_open = virtnet_open,
> > .ndo_stop = virtnet_close,
> > @@ -1437,7 +1426,6 @@ static const struct net_device_ops virtnet_netdev = {
> > .ndo_validate_addr = eth_validate_addr,
> > .ndo_set_mac_address = virtnet_set_mac_address,
> > .ndo_set_rx_mode = virtnet_set_rx_mode,
> > - .ndo_change_mtu = virtnet_change_mtu,
> > .ndo_get_stats64 = virtnet_stats,
> > .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
> > .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
> > @@ -1748,6 +1736,9 @@ static bool virtnet_validate_features(struct virtio_device *vdev)
> > return true;
> > }
> >
> > +#define MIN_MTU ETH_MIN_MTU
> > +#define MAX_MTU 65535
> > +
>
> Do we need a common macro for this?
I think it's actually IP_MAX_MTU.
> > static int virtnet_probe(struct virtio_device *vdev)
> > {
> > int i, err;
> > @@ -1821,6 +1812,10 @@ static int virtnet_probe(struct virtio_device *vdev)
> >
> > dev->vlan_features = dev->features;
> >
> > + /* MTU range: 68 - 65535 */
> > + dev->min_mtu = MIN_MTU;
> > + dev->max_mtu = MAX_MTU;
> > +
> > /* Configuration may specify what MAC to use. Otherwise random. */
> > if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
> > virtio_cread_bytes(vdev,
> > @@ -1875,8 +1870,10 @@ static int virtnet_probe(struct virtio_device *vdev)
> > mtu = virtio_cread16(vdev,
> > offsetof(struct virtio_net_config,
> > mtu));
> > - if (virtnet_change_mtu(dev, mtu))
> > + if (mtu >= dev->min_mtu && mtu <= dev->max_mtu) {
> > + dev->mtu = mtu;
> > __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
>
> I think the logic is wrong here:
>
> If mtu is legal, we set it but do not tell host.
> If it's out of range we tell host we use it
> but don't actually.
>
> Should be the reverse.
>
> > + }
> > }
> >
> > if (vi->any_header_sg)
>
> --
> MST
next prev parent reply other threads:[~2016-10-19 14:03 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-10-19 2:33 [PATCH net-next 0/6] net: use core MTU range checking everywhere Jarod Wilson
2016-10-19 2:33 ` [PATCH net-next 1/6] net: use core MTU range checking in USB NIC drivers Jarod Wilson
2016-10-19 2:33 ` [PATCH net-next 2/6] net: use core MTU range checking in wireless drivers Jarod Wilson
2016-10-19 7:38 ` Johannes Berg
2016-10-19 14:27 ` Jarod Wilson
2016-10-19 14:28 ` Johannes Berg
2016-10-19 2:33 ` [PATCH net-next 3/6] net: use core MTU range checking in WAN drivers Jarod Wilson
2016-10-21 12:04 ` Krzysztof Hałasa
2016-10-19 2:33 ` [PATCH net-next 4/6] net: use core MTU range checking in core net infra Jarod Wilson
2016-10-19 12:17 ` Jiri Benc
2016-10-19 14:51 ` Jarod Wilson
2016-10-19 13:55 ` Sabrina Dubroca
2016-10-19 14:40 ` Jarod Wilson
2016-10-19 15:28 ` Sabrina Dubroca
2016-10-19 15:46 ` Jarod Wilson
2016-10-19 2:33 ` [PATCH net-next 5/6] net: use core MTU range checking in virt drivers Jarod Wilson
2016-10-19 13:06 ` Aaron Conole
2016-10-19 13:59 ` Michael S. Tsirkin
2016-10-19 14:03 ` Michael S. Tsirkin [this message]
2016-10-19 14:17 ` Jarod Wilson
2016-10-19 14:15 ` Jarod Wilson
2016-10-19 14:07 ` Haiyang Zhang via Virtualization
2016-10-19 14:23 ` Jarod Wilson
2016-10-19 22:21 ` Shrikrishna Khare
2016-10-19 2:33 ` [PATCH net-next 6/6] net: use core MTU range checking in misc drivers Jarod Wilson
2016-10-19 14:37 ` Robin Holt
2016-10-19 16:05 ` Sabrina Dubroca
2016-10-19 22:38 ` Stefan Richter
2016-10-20 3:16 ` Jarod Wilson
[not found] ` <20161020031641.GJ18569-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2016-10-22 9:36 ` Stefan Richter
2016-10-22 18:51 ` Stefan Richter
2016-10-19 19:10 ` [PATCH net-next 0/6] net: use core MTU range checking everywhere David Miller
2016-10-19 19:29 ` Jarod Wilson
2016-10-20 17:55 ` [PATCH net-next v2 0/9] " Jarod Wilson
2016-10-20 17:55 ` [PATCH net-next v2 1/9] ethernet: use net core MTU range checking in more drivers Jarod Wilson
2016-10-20 17:55 ` [PATCH net-next v2 2/9] net: use core MTU range checking in USB NIC drivers Jarod Wilson
2016-10-20 17:55 ` [PATCH net-next v2 3/9] net: use core MTU range checking in wireless drivers Jarod Wilson
2016-10-20 18:22 ` Johannes Berg
2016-10-20 18:38 ` David Miller
2016-10-20 17:55 ` [PATCH net-next v2 4/9] net: use core MTU range checking in WAN drivers Jarod Wilson
2016-10-20 17:55 ` [PATCH net-next v2 5/9] net: use core MTU range checking in core net infra Jarod Wilson
2016-10-20 17:55 ` [PATCH net-next v2 6/9] net: use core MTU range checking in virt drivers Jarod Wilson
2016-10-20 18:05 ` Haiyang Zhang
2016-10-20 20:12 ` Kershner, David A
2016-10-20 20:23 ` Michael S. Tsirkin
2016-10-21 2:37 ` Jarod Wilson
2016-10-21 3:36 ` Michael S. Tsirkin
2016-10-21 13:24 ` Aaron Conole
2016-10-21 10:09 ` Wei Liu
2016-10-20 17:55 ` [PATCH net-next v2 7/9] net: use core MTU range checking in misc drivers Jarod Wilson
2016-10-21 6:52 ` Rémi Denis-Courmont
2016-10-21 16:22 ` Sebastian Reichel
[not found] ` <20161020175524.6184-8-jarod-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2016-10-22 7:17 ` [net-next,v2,7/9] " Sven Eckelmann
2016-10-22 19:16 ` [PATCH net-next v2 7/9] " Stefan Richter
2016-10-22 19:27 ` Stefan Richter
2016-10-23 1:18 ` Jarod Wilson
2016-10-23 14:29 ` [PATCH net-next 1/2] firewire: net: fix maximum possible MTU Stefan Richter
2016-10-23 14:30 ` [PATCH net-next 2/2] firewire: net: set initial MTU = 1500 unconditionally, fix IPv6 on some CardBus cards Stefan Richter
2016-10-24 1:50 ` Jarod Wilson
2016-10-24 12:26 ` [PATCH net-next 2/2 v2] " Stefan Richter
2016-10-25 3:05 ` Jarod Wilson
2016-10-26 21:29 ` [PATCH net-next 2/2] " David Miller
2016-10-29 20:16 ` [PATCH net-next] firewire: net: really fix maximum possible MTU Stefan Richter
2016-10-30 3:01 ` David Miller
2016-10-24 1:50 ` [PATCH net-next 1/2] firewire: net: " Jarod Wilson
2016-10-26 21:29 ` David Miller
2016-10-20 17:55 ` [PATCH net-next v2 8/9] s390/net: use net core MTU range checking Jarod Wilson
2016-10-20 17:55 ` [PATCH net-next v2 9/9] ipv4/6: use core net " Jarod Wilson
2016-10-20 18:53 ` [PATCH net-next v2 0/9] net: use core MTU range checking everywhere David Miller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20161019170330-mutt-send-email-mst@kernel.org \
--to=mst@redhat.com \
--cc=haiyangz@microsoft.com \
--cc=jarod@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=pv-drivers@vmware.com \
--cc=skhare@vmware.com \
--cc=virtualization@lists.linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).