From d68b73e2f1c09e64e7f37a766a1b6190088c97da Mon Sep 17 00:00:00 2001 From: Mike Pattrick Date: Thu, 16 Jan 2025 00:21:30 -0500 Subject: [PATCH] docs: Update userspace TSO tunnel fallback documentation. Previously support was added for VXLAN and Geneve tunnels in the TSO software fallback. However, the documentation was not updated appropriately. Now the documentation is brought up to date and a NEWS item is added. Fixes: 82c1028e371e ("Userspace: Software fallback for UDP encapsulated TCP segmentation.") Acked-by: David Marchand Signed-off-by: Mike Pattrick Signed-off-by: Ilya Maximets --- Documentation/topics/userspace-tso.rst | 11 +++++------ NEWS | 2 ++ 2 files changed, 7 insertions(+), 6 deletions(-) diff --git a/Documentation/topics/userspace-tso.rst b/Documentation/topics/userspace-tso.rst index d60abca0e..3e530f5ac 100644 --- a/Documentation/topics/userspace-tso.rst +++ b/Documentation/topics/userspace-tso.rst @@ -120,12 +120,11 @@ in Open vSwitch. Currently, if the NIC supports that, then the feature is enabled, otherwise TSO can still be enabled but SCTP packets sent to the NIC will be dropped. -There is no software implementation of TSO in conjunction with tunnels. So -when VxLAN or Geneve tunnels are in use, all ports attached to the datapath -must support TSO or packets using this combination of features will be dropped -on ports without hardware TSO support. That also means guests using -vhost-user in client mode will receive TSO packet regardless of TSO being -enabled or disabled within the guest. +There is a limited software implementation of TSO when tunnels are used which +only supports VxLAN and Geneve. When these tunnels are used with TSO, +not all ports attached to the datapath need to support hardware TSO. +Guests using vhost-user in client mode will receive TSO packet regardless of +TSO being enabled or disabled within the guest. All kernel devices that use the raw socket interface (veth, for example) require the kernel commit 9d2f67e43b73 ("net/packet: fix packet drop as of diff --git a/NEWS b/NEWS index 1aedbbe44..32f08843c 100644 --- a/NEWS +++ b/NEWS @@ -31,6 +31,8 @@ Post-v3.4.0 that does not have a specific value defined, rather than being treated as a global value, aligning the behavior with that of the kernel datapath. + * Extended the support for TSO software fallback to include support for + VXLAN and Geneve tunneled packets. - Linux TC offload: * Add support for matching tunnel flags if the kernel supports it. * Add support for the "Don't Fragment" (DF) flag in the encap action,