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Date:   Wed, 24 May 2023 08:15:23 +0100
From:   Lorenzo Stoakes <lstoakes@gmail.com>
To:     David Hildenbrand <david@redhat.com>
Cc:     Vlastimil Babka <vbabka@suse.cz>, Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Hyeonggon Yoo <42.hyeyoo@gmail.com>,
        Kees Cook <keescook@chromium.org>, linux-mm@kvack.org,
        linux-hardening@vger.kernel.org, patches@lists.linux.dev,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/slab: remove HAVE_HARDENED_USERCOPY_ALLOCATOR
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On Tue, May 23, 2023 at 10:28:32AM +0200, David Hildenbrand wrote:
[snip]
> > > The file is only compiled with CONFIG_HARDENED_USERCOPY:
> > >
> > > mm/Makefile:obj-$(CONFIG_HARDENED_USERCOPY) += usercopy.o
> > >
> >
> > Yeah ugh at this sort of implicit thing. Anyway it'd be preferable to stick
> > #ifdef CONFIG_HARDENED_USERCOPY around the prototype just so it's
> > abundantly clear this function doesn't exist unless that is set.
>
> I recall that it is very common to not use ifdefs unless really required.
> Because less ifefs are obviously preferable ;)
>
> Compilation+linking will fail in any case.
>

I don't want to insist so hard on something that doesn't really matter, the
bike shed can be blue, green or red it's fine :P

So,

Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>