Re: [PATCH] docs/about: Automatically deprecate versioned machine types older than 6 years

[Philippe Mathieu-Daudé]

Hi Thomas,

On 30/4/24 08:45, Thomas Huth wrote:
> Old machine types often have bugs or work-arounds that affect our
> possibilities to move forward with the QEMU code base (see for example
> https://gitlab.com/qemu-project/qemu/-/issues/2213 for a bug that likely
> cannot be fixed without breaking live migration with old machine types,
> or https://lists.gnu.org/archive/html/qemu-devel/2018-12/msg04516.html or
> commit ea985d235b86). So instead of going through the process of manually
> deprecating old machine types again and again, let's rather add an entry
> that can stay, which declares that machine types older than 6 years are
> considered as deprecated automatically. Six years should be sufficient to
> support the release cycles of most Linux distributions.

Thanks for taking that out of my plate :)

IIRC 6 years was because of some old RHEL version, otherwise could
5 years be enough? (maybe it could be good enough for this old RHEL
version as of QEMU v10.0).

> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
>   docs/about/deprecated.rst | 11 +++++++++++
>   1 file changed, 11 insertions(+)
>
> diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
> index 6d595de3b6..fe69e2d44c 100644
> --- a/docs/about/deprecated.rst
> +++ b/docs/about/deprecated.rst
> @@ -220,6 +220,17 @@ is a chance the code will bitrot without anyone noticing.
>   System emulator machines
>   ------------------------
>   
> +Versioned machine types older than 6 years
> +''''''''''''''''''''''''''''''''''''''''''
> +
> +Starting with the release of QEMU 10.0, versioned machine types older than

Why can't we start with QEMU 9.1?

> +6 years will automatically be considered as deprecated and might be due to
> +removal without furthor notice. For example, this affects machine types like
> +pc-i440fx-X.Y, pc-q35-X.Y, pseries-X.Y, s390-ccw-virtio-X.Y or virt-X.Y where
> +X is the major number and Y is the minor number of the old QEMU version.
> +If you are still using machine types from QEMU versions older than 6 years,
> +please update your setting to use a newer versioned machine type instead.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>