Re: CSME firmware / host coexistence - grab the CSME connection info params

[Thomas Haller <thaller redhat com>]

On Sat, 2022-02-26 at 23:37 +0200, Emmanuel Grumbach via
networkmanager-list wrote:
> Hi,
>
> I'd like to get some guidance on how to continue the implementation
> of the CSME firmware coexistence.
> We now need to fetch the connection parameters from CSME (through the
> kernel). There is a vendor command API in the kernel. This works
> above the nl80211 channel.
>
> So should I include the header file in src/libnm-platform/wifi/nm-
> wifi-utils-nl80211.c ?
> OTOH, only recent kernels have this header, so what's the way to ask:
> try to include this, if you don't have it, let's disable the feature?
> Should I use this type of ifdef:
> #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 27)
> ?
> Do you prefer to have a separate nm-wifi-utils-intel-vnd.c file since
> it exists only as an Intel Vendor command?
> Should I create a new handler in NMWifiUtilsClass for that purpose?
>
> Then, the nm core code could use the NMWifiUtilsClass to fetch the
> data when it sees that RFKILL is asserted with the reason =
> "OS_NOT_OWNER".
>
> Thanks :)

Hi,


Btw, what means "vendor" when you say "vendor command API"? It is kinda
important to us, is that the feature can be used with an upstream
kernel (without propritary modules -- and preferably only with upstream
modules).


Which header is this?

Usually, we want to build a version of NetworkManager that supports
most features, regardless against which kernel (headers) it was build. 
Because, you should be able to upgrade your kernel and get the feature
automatically. It means, we would rather fail at runtime, if kernel
doens't support it.
That means, we either add a fork of the header in `src/linux-headers`.
Alternatively, if we only require a few defines, you can copy them
directly to the source file where needed. It depends on how much is
needed.

If this gets fetched via nl80211, then  src/libnm-platform/wifi/nm-
wifi-utils-nl80211.c is the right place.




best,
Thomas