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Date:   Sat, 19 Feb 2022 15:58:51 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-kernel@vger.kernel.org, stable <stable@vger.kernel.org>,
        Daniel Micay <danielmicay@gmail.com>,
        Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Nathan Chancellor <nathan@kernel.org>, linux-mm@kvack.org,
        llvm@lists.linux.dev
Subject: Re: [PATCH] slab: remove __alloc_size attribute from
 __kmalloc_track_caller
Message-ID: <202202191558.11C173F04@keescook>
References: <20220218131358.3032912-1-gregkh@linuxfoundation.org>
 <CAKwvOd=4uwMVBwYU8XPP+cHkw5V1S_t7i8psMTRySsKEcDVZ_A@mail.gmail.com>
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On Fri, Feb 18, 2022 at 09:19:51AM -0800, Nick Desaulniers wrote:
> On Fri, Feb 18, 2022 at 5:14 AM Greg Kroah-Hartman
> <gregkh@linuxfoundation.org> wrote:
> >
> > Commit c37495d6254c ("slab: add __alloc_size attributes for better
> > bounds checking") added __alloc_size attributes to a bunch of kmalloc
> > function prototypes.  Unfortunately the change to __kmalloc_track_caller
> > seems to cause clang to generate broken code and the first time this is
> > called when booting, the box will crash.
> >
> > While the compiler problems are being reworked and attempted to be
> > solved, let's just drop the attribute to solve the issue now.  Once it
> > is resolved it can be added back.
> 
> Sorry about the mess; we'll get it cleaned up!
> Acked-by: Nick Desaulniers <ndesaulniers@google.com>
> Link: https://github.com/ClangBuiltLinux/linux/issues/1599

Thanks for the issue link!

Acked-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook