You may not be able to distribute the combined work without violating the copyright of the GPL part, even if the other part is not a derivative work of the GPL

You may not be able to distribute the combined work without violating the copyright of the GPL part, even if the other part is not a derivative work of the GPL part. If you really just distribute your part and let the user go and fetch the GPL part by his own means, the FSF has absolutely no say (and this is kind of what most propietary .ko kind of do); but if you also distribute the GPL part to the user... I.e. if you never distribute/reproduce the GPL part, then the GPL obviously can not apply; if you distribute the GPL part, then the GPL terms apply to you, even if your work is not derivative, and even if those terms are "you must do the chicken dance so that we give permission to reproduce our software"; after all, that is how most EULAs are enforced. It just happens that in this case the chicken dance comprises some fancy definitions of linking and some extra things you may have to distribute rather than a exchange of money.