Of course it's not a bug. We type www in front of every domain name to tell the browser we want the Web page and not an FTP site, right?
(Yes, I'm being sarcastic.)
Also... m.lwn.net doesn't exist so far as I can tell. I'm getting DNS failures on both my desktop (Comcast) and phone (Sprint). LWN has always been a pain in the ass to read and use on a phone in my experience, especially when it comes to commenting (iOS devices tend to get especially very confused and lose the scrollbars in the comment fields). If there's a better way to use it, it's clearly not made obvious (or better yet, automatic).
On the upside, at least it's not as bad as the horrendous (if occasionally informative) Phoronix is. That site is a nightmare to use on a desktop with its "oops I moused over a hover-link on the way to trying to click a regular link, and now I have a page-size Flash ad" setup, and it's basically unusable on a phone.