* Linus Torvalds <torva...@linux-foundation.org> wrote: > On Wed, Aug 5, 2015 at 10:48 AM, Ingo Molnar <mi...@kernel.org> wrote: > >> > >> Some of these field names are visible to userspace and can't change. > > > > That's a misconception: bits in the uapi headers can be renamed just fine. > > I disagree. If it causes pain for user space, we just shouldn't do it.
Ok, agreed - I wanted to argue against the "can't change" statement and went overboard with my own statement ... Quite often headers can change and we've changed a number of fields in the past - but if they cause pain (as in this case) we don't do it. So I'd say that based on past experience: - changing small details in uapi headers is usually fine. - changing small details in the ABI is usually not fine. If anything breaks then the policy is the same, regardless of likelihood: reverting the change. > Some people copy the headers (preferred), others include the kernel header > directory with a include path or a symlink, and it's damn painful if we start > changing things that user space depends on. > > I'd say that it's like the ABI - if people don't really notice, you can do > it, > but if it breaks the build of a user app, we should be very very careful. The > breakage is often hard to fix because of nasty versioning issues.. > > Our goal in life really is "don't screw up user space". Yeah, agreed 100%. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/