I'm not sure I see the link between it being a character device and the fact that memory pages are W^X. But you are correct that I was wrong when saying you can

I'm not sure I see the link between it being a character device and the fact that memory pages are W^X. But you are correct that I was wrong when saying you can't have it; I also said it was more complex since you have to be careful when switch a page from W to X.