Re: [PATCH mm] kfence, slab: fix cache_alloc_debugcheck_after() for bulk allocations

Alexander Potapenko
2021-03-05T08:58:13Z

On Fri, Mar 5, 2021 at 2:31 AM Andrew Morton <akpm@linux-foundation.org> wrote:
>
> On Thu, 4 Mar 2021 22:05:48 +0100 Alexander Potapenko <glider@google.com> wrote:
>
> > On Thu, Mar 4, 2021 at 9:53 PM Marco Elver <elver@google.com> wrote:
> > >
> > > cache_alloc_debugcheck_after() performs checks on an object, including
> > > adjusting the returned pointer. None of this should apply to KFENCE
> > > objects. While for non-bulk allocations, the checks are skipped when we
> > > allocate via KFENCE, for bulk allocations cache_alloc_debugcheck_after()
> > > is called via cache_alloc_debugcheck_after_bulk().
> >
> > @Andrew, is this code used by anyone?
> > As far as I understand, it cannot be enabled by any config option, so
> > nobody really tests it.
> > If it is still needed, shall we promote #if DEBUGs in slab.c to a
> > separate config option, or maybe this code can be safely removed?
>
> It's all used:

Got it, sorry for being too hasty!