Re: [PATCH v3] mm, slub: change run-time assertion in kmalloc_index() to compile-time

From: Hyeonggon Yoo
Date: Thu May 13 2021 - 08:38:41 EST

On Thu, May 13, 2021 at 02:29:13PM +0200, Marco Elver wrote:
> On Thu, 13 May 2021 at 14:03, Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx> wrote:
> > On Thu, May 13, 2021 at 12:31:38PM +0200, Marco Elver wrote:
> [...]
> > what about checking size it on top of kmalloc_index? because by definition of
> > KMALLOC_SHIFT_HIGH, it's not always 25. it can be less than 25. for some
> > situations.
> >
> > below is what I suggested beofre. for just reference:
> This doesn't solve the problem. We want the compiler to complain
> whenever kmalloc_index() is used with non-constant in normal code.

in the beginning, I thought kmalloc_index is called only from kmalloc.
but if kmalloc_index is called from other place, I think it should
correctly check its size. that's what kmalloc_index should do.

or... should it be solved as another patch?