From: Stephen Hemminger <stephen@networkplumber.org>
To: yliu@fridaylinux.org, maxime.coquelin@redhat.com
Cc: dev@dpdk.org, Stephen Hemminger <stephen@networkplumber.org>
Subject: [dpdk-dev] [PATCH 1/2] virtio: don't falsely claim to do IP checksum
Date: Fri, 7 Jul 2017 12:52:49 -0700 [thread overview]
Message-ID: <20170707195250.22259-2-stephen@networkplumber.org> (raw)
In-Reply-To: <20170707195250.22259-1-stephen@networkplumber.org>
The virtio driver is confused about the meaning of the ip_checksum
flag. In DPDK, ip_checksum means the hardware is capable of checking
the Layer 3 IP checksum. But KVM/QEMU does not do that. The flag
VIRTIO_NET_F_GUEST_CSUM controls whether the receive side does
Layer 4 (TCP/UDP) checksum offload.
Fix by erroring out any requests to do IP checksum.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
drivers/net/virtio/virtio_ethdev.c | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)
diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 5c826f47740c..ca607904fa37 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1664,8 +1664,13 @@ virtio_dev_configure(struct rte_eth_dev *dev)
PMD_INIT_LOG(DEBUG, "configure");
req_features = VIRTIO_PMD_DEFAULT_GUEST_FEATURES;
- if (rxmode->hw_ip_checksum)
- req_features |= (1ULL << VIRTIO_NET_F_GUEST_CSUM);
+
+ /* Virtio does L4 checksum but not L3! */
+ if (rxmode->hw_ip_checksum) {
+ PMD_DRV_LOG(NOTICE,
+ "virtio does not support IP checksum");
+ return -ENOTSUP;
+ }
if (rxmode->enable_lro)
req_features |=
(1ULL << VIRTIO_NET_F_GUEST_TSO4) |
@@ -1678,13 +1683,6 @@ virtio_dev_configure(struct rte_eth_dev *dev)
return ret;
}
- if (rxmode->hw_ip_checksum &&
- !vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_CSUM)) {
- PMD_DRV_LOG(NOTICE,
- "rx ip checksum not available on this host");
- return -ENOTSUP;
- }
-
if (rxmode->enable_lro &&
(!vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_TSO4) ||
!vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_TSO4))) {
--
2.11.0
next prev parent reply other threads:[~2017-07-07 19:53 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-07-07 19:52 [dpdk-dev] [PATCH 0/2] virtio fix false offload claims Stephen Hemminger
2017-07-07 19:52 ` Stephen Hemminger [this message]
2017-07-07 19:52 ` [dpdk-dev] [PATCH 2/2] virtio: don't claim to support LRO Stephen Hemminger
2017-07-08 3:12 ` [dpdk-dev] [PATCH 0/2] virtio fix false offload claims Yuanhan Liu
2017-08-23 9:30 ` Olivier MATZ
2017-08-23 15:31 ` Stephen Hemminger
2017-08-23 16:14 ` Olivier MATZ
2017-08-23 16:41 ` Stephen Hemminger
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=20170707195250.22259-2-stephen@networkplumber.org \
--to=stephen@networkplumber.org \
--cc=dev@dpdk.org \
--cc=maxime.coquelin@redhat.com \
--cc=yliu@fridaylinux.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).