From: "Michael S. Tsirkin" <mst@redhat.com>
To: Simon Horman <horms@kernel.org>
Cc: Daniel Jurgens <danielj@nvidia.com>,
netdev@vger.kernel.org, jasowang@redhat.com,
xuanzhuo@linux.alibaba.com, virtualization@lists.linux.dev,
davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
pabeni@redhat.com, jiri@nvidia.com
Subject: Re: [PATCH net-next 2/4] virtio_net: Remove command data from control_buf
Date: Thu, 28 Mar 2024 11:29:22 -0400 [thread overview]
Message-ID: <20240328112856-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <20240328133516.GK403975@kernel.org>
On Thu, Mar 28, 2024 at 01:35:16PM +0000, Simon Horman wrote:
> On Mon, Mar 25, 2024 at 04:49:09PM -0500, Daniel Jurgens wrote:
> > Allocate memory for the data when it's used. Ideally the could be on the
> > stack, but we can't DMA stack memory. With this change only the header
> > and status memory are shared between commands, which will allow using a
> > tighter lock than RTNL.
> >
> > Signed-off-by: Daniel Jurgens <danielj@nvidia.com>
> > Reviewed-by: Jiri Pirko <jiri@nvidia.com>
>
> ...
>
> > @@ -3893,10 +3925,16 @@ static int virtnet_restore_up(struct virtio_device *vdev)
> >
> > static int virtnet_set_guest_offloads(struct virtnet_info *vi, u64 offloads)
> > {
> > + u64 *_offloads __free(kfree) = NULL;
> > struct scatterlist sg;
> > - vi->ctrl->offloads = cpu_to_virtio64(vi->vdev, offloads);
> >
> > - sg_init_one(&sg, &vi->ctrl->offloads, sizeof(vi->ctrl->offloads));
> > + _offloads = kzalloc(sizeof(*_offloads), GFP_KERNEL);
> > + if (!_offloads)
> > + return -ENOMEM;
> > +
> > + *_offloads = cpu_to_virtio64(vi->vdev, offloads);
>
> Hi Daniel,
>
> There is a type mismatch between *_offloads and cpu_to_virtio64
> which is flagged by Sparse as follows:
>
> .../virtio_net.c:3978:20: warning: incorrect type in assignment (different base types)
> .../virtio_net.c:3978:20: expected unsigned long long [usertype]
> .../virtio_net.c:3978:20: got restricted __virtio64
>
> I think this can be addressed by changing the type of *_offloads to
> __virtio64 *.
Yes pls, endian-ness is easier to get right 1st time than fix
afterwards.
> > +
> > + sg_init_one(&sg, _offloads, sizeof(*_offloads));
> >
> > if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
> > VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, &sg)) {
> > --
> > 2.42.0
> >
> >
next prev parent reply other threads:[~2024-03-28 15:29 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-25 21:49 [PATCH net-next 0/4] Remove RTNL lock protection of CVQ Daniel Jurgens
2024-03-25 21:49 ` [PATCH net-next 1/4] virtio_net: Store RSS setting in virtnet_info Daniel Jurgens
2024-03-25 21:49 ` [PATCH net-next 2/4] virtio_net: Remove command data from control_buf Daniel Jurgens
2024-03-26 7:06 ` Heng Qi
2024-03-28 13:35 ` Simon Horman
2024-03-28 15:29 ` Michael S. Tsirkin [this message]
2024-03-25 21:49 ` [PATCH net-next 3/4] virtio_net: Add a lock for the command VQ Daniel Jurgens
2024-03-25 21:49 ` [PATCH net-next 4/4] virtio_net: Remove rtnl lock protection of command buffers Daniel Jurgens
2024-03-26 8:54 ` Heng Qi
2024-03-26 15:18 ` Dan Jurgens
2024-03-27 2:10 ` Heng Qi
2024-03-27 12:00 ` Heng Qi
2024-03-26 1:33 ` [PATCH net-next 0/4] Remove RTNL lock protection of CVQ Xuan Zhuo
2024-03-26 2:54 ` Heng Qi
2024-03-26 4:11 ` Dan Jurgens
2024-03-26 6:05 ` Heng Qi
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=20240328112856-mutt-send-email-mst@kernel.org \
--to=mst@redhat.com \
--cc=danielj@nvidia.com \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=horms@kernel.org \
--cc=jasowang@redhat.com \
--cc=jiri@nvidia.com \
--cc=kuba@kernel.org \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=virtualization@lists.linux.dev \
--cc=xuanzhuo@linux.alibaba.com \
/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 read-only IMAP folder(s) and NNTP newsgroup(s).