Re: [PATCH] xen/pvcalls: backend can be a module

From: Stefano Stabellini
Date: Tue Sep 07 2021 - 20:49:27 EST


On Tue, 7 Sep 2021, Jan Beulich wrote:
> It's not clear to me why only the frontend has been tristate. Switch the
> backend to be, too.
>
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

Actually although the frontend is a tristate, it cannot really work as a
module. Specifically see pvcalls_stream_ops in the enabling patch (still
not upstream):

https://github.com/lf-edge/runx/blob/master/kernel/patches/0001-patch-pvcalls_enable.patch


So I had to change tristate to bool for XEN_PVCALLS_FRONTEND in our
internal kernel tree.

That said, the PVCalls backend could very well be a module and
technically I don't see any reasons why not. So:


Acked-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>



> --- a/drivers/xen/Kconfig
> +++ b/drivers/xen/Kconfig
> @@ -214,7 +214,7 @@ config XEN_PVCALLS_FRONTEND
> implements them.
>
> config XEN_PVCALLS_BACKEND
> - bool "XEN PV Calls backend driver"
> + tristate "XEN PV Calls backend driver"
> depends on INET && XEN && XEN_BACKEND
> help
> Experimental backend for the Xen PV Calls protocol
>