On Tue, 17 Apr 2012 22:39:15 -0300 Paulo Zanoni <przanoni at gmail.com> wrote: > 2012/4/16 Ben Widawsky <ben at bwidawsk.net>: > > Sparse doesn't like: > > "error: bad constant expression" > > > > <bikeshedding> > I know you'll hate me for asking, but: how difficult is it to fix sparse? > Adding those mallocs/frees increases the code complexity, making it > harder to read... > </bikeshedding> > I don't consider this a bikeshed. I've always been "under the impression" C99 was sort of taboo in the kernel. In this case specifically, it's never a great idea to allocate an unknown amount of stack space as it probably messes with some of the static tools and such. In other words, I believe the right thing to do here is not to fix sparse. Plus there is precedent in other drivers to fix this kind of thing for sparse. I originally had this patch create an arbitrarily large object on the stack and fail if the args_len was too big. I can go back to that certainly if people prefer.
