Re: [RFC PATCH 8/9] block: genhd: export-GPL generic disk device type

[Greg Kroah-Hartman]

On Thu, Apr 09, 2020 at 03:35:42PM -0400, Mathieu Desnoyers wrote:
> Iteration on class devices is exported for use by GPL modules, but
> there is no exported function for getting the generic disk device type
> which is required to perform iteration on the generic disks.
> 
> Export a new getter for disk device type for use by GPL modules. This is
> useful for tracing a meaningful list of block devices from tracers
> implemented as GPL modules.
> 
> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
> Cc: Tejun Heo <tj@xxxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> ---
>  block/genhd.c         | 9 +++++++++
>  include/linux/genhd.h | 2 ++
>  2 files changed, 11 insertions(+)

I understand your need here, however we do not export things for
modules, when there are no in-kernel module users, sorry.

I have your last thread somewhere in my todo pile, to try to respond as
to how to make this not be an issue for you, sorry I haven't gotten to
it.

Why can't you just add a tracepoint instead of having to dig through
this mess?  Wouldn't that solve a lot of these issues for block devices?

thanks,

greg k-h