Re: [PATCH v3 01/11] tap: Remove tap_probe_vnet_hdr_len()

[Michael S. Tsirkin]

On Fri, Oct 13, 2023 at 01:14:32PM +0900, Akihiko Odaki wrote:
> On 2023/10/13 10:38, Jason Wang wrote:
> > On Wed, Oct 11, 2023 at 11:40 PM Akihiko Odaki <akihiko.odaki@daynix.com> 
> > wrote:
> > > 
> > > It was necessary since an Linux older than 2.6.35 may implement the
> > > virtio-net header but may not allow to change its length. Remove it
> > > since such an old Linux is no longer supported.
> > 
> > Where can I see this agreement?
> 
> docs/about/build-platforms.rst says:
> > The project aims to support the most recent major version at all times
> > for up to five years after its initial release. Support for the
> > previous major version will be dropped 2 years after the new major
> > version is released or when the vendor itself drops support, whichever
> > comes first. In this context, third-party efforts to extend the
> > lifetime of a distro are not considered, even when they are endorsed
> > by the vendor (eg. Debian LTS); the same is true of repositories that
> > contain packages backported from later releases (e.g. Debian
> > backports). Within each major release, only the most recent minor
> > release is considered.
> >
> > For the purposes of identifying supported software versions available
> > on Linux, the project will look at CentOS, Debian, Fedora, openSUSE,
> > RHEL, SLES and Ubuntu LTS. Other distros will be assumed to ship
> > similar software versions.
> 
> All of the previous major versions of these distributions ship far newer
> kernels.
> 
> CentOS Stream 8 and RHEL 8 ship 4.18.0.

Yes but RHEL7 is still in full support.

> Debian bullseye ships 5.10.0.
> Fedora 37 ships 6.5.6.
> openSUSE Leap 15.4 ships 5.14.21.
> SLES 12 ships 4.12.14.
> Ubuntu 20.04 ships 5.4.

It does not matter that a newer version is shipped. What matters is
whether older one is still supported.