Re: [PATCH bpf-next v2 07/28] bpf/hid: add a new attach type to change the report descriptor

From: Greg KH
Date: Fri Mar 04 2022 - 13:33:04 EST


On Fri, Mar 04, 2022 at 06:28:31PM +0100, Benjamin Tissoires wrote:
> The report descriptor is the dictionary of the HID protocol specific
> to the given device.
> Changing it is a common habit in the HID world, and making that feature
> accessible from eBPF allows to fix devices without having to install a
> new kernel.
>
> However, the report descriptor is supposed to be static on a device.
> To be able to change it, we need to reconnect the device at the HID
> level.
> So whenever the report descriptor program type is attached or detached,
> we call on a hook on HID to notify it that there is something to be
> done.
>
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>

Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>