Re: [PATCH RFC v3 07/36] kmsan: introduce __no_sanitize_memory and __SANITIZE_MEMORY__

From: Alexander Potapenko <glider@google.com>
To: Andrey Konovalov <andreyknvl@google.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	 Linux Memory Management List <linux-mm@kvack.org>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	 Andreas Dilger <adilger.kernel@dilger.ca>,
	Andrew Morton <akpm@linux-foundation.org>,
	 Andrey Ryabinin <aryabinin@virtuozzo.com>,
	Andy Lutomirski <luto@kernel.org>,
	 Ard Biesheuvel <ard.biesheuvel@linaro.org>,
	Arnd Bergmann <arnd@arndb.de>,
	 Christoph Hellwig <hch@infradead.org>,
	Christoph Hellwig <hch@lst.de>,
	 "Darrick J. Wong" <darrick.wong@oracle.com>,
	"David S. Miller" <davem@davemloft.net>,
	 Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	Eric Biggers <ebiggers@google.com>,
	 Eric Dumazet <edumazet@google.com>,
	Eric Van Hensbergen <ericvh@gmail.com>,
	 Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Harry Wentland <harry.wentland@amd.com>,
	 Herbert Xu <herbert@gondor.apana.org.au>,
	Ilya Leoshkevich <iii@linux.ibm.com>,
	 Ingo Molnar <mingo@elte.hu>, Jason Wang <jasowang@redhat.com>,
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	 Marek Szyprowski <m.szyprowski@samsung.com>,
	Marco Elver <elver@google.com>,
	 Mark Rutland <mark.rutland@arm.com>,
	"Martin K. Petersen" <martin.petersen@oracle.com>,
	 Martin Schwidefsky <schwidefsky@de.ibm.com>,
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	 "Michael S . Tsirkin" <mst@redhat.com>,
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	 Qian Cai <cai@lca.pw>, Randy Dunlap <rdunlap@infradead.org>,
	Robin Murphy <robin.murphy@arm.com>,
	 Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
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	 Takashi Iwai <tiwai@suse.com>, "Theodore Ts'o" <tytso@mit.edu>,
	Thomas Gleixner <tglx@linutronix.de>,
	 Vasily Gorbik <gor@linux.ibm.com>,
	Wolfram Sang <wsa@the-dreams.de>
Subject: Re: [PATCH RFC v3 07/36] kmsan: introduce __no_sanitize_memory and __SANITIZE_MEMORY__
Date: Mon, 16 Dec 2019 12:35:03 +0100	[thread overview]
Message-ID: <CAG_fn=WVQpBgxh2mYBdtnomUhFWDykTn9+QkTXYmOV5a3q_xWQ@mail.gmail.com> (raw)
In-Reply-To: <CAAeHK+xjTZSUnzAw8c28WjN5mpZcg2Dek+S+9tuRhkYf2AgtZQ@mail.gmail.com>

On Fri, Nov 29, 2019 at 5:09 PM Andrey Konovalov <andreyknvl@google.com> wrote:
>
> On Fri, Nov 22, 2019 at 12:26 PM <glider@google.com> wrote:
> >
> > __no_sanitize_memory is a function attribute that makes KMSAN
> > ignore the uninitialized values coming from the function's
> > inputs, and initialize the function's outputs.
> >
> > Functions marked with this attribute can't be inlined into functions
> > not marked with it, and vice versa.
> >
> > __SANITIZE_MEMORY__ is a macro that's defined iff the file is
> > instrumented with KMSAN. This is not the same as CONFIG_KMSAN, which is
> > defined for every file.
> >
> > Signed-off-by: Alexander Potapenko <glider@google.com>
> > To: Alexander Potapenko <glider@google.com>
> > Cc: Vegard Nossum <vegard.nossum@oracle.com>
> > Cc: Dmitry Vyukov <dvyukov@google.com>
> > Cc: linux-mm@kvack.org
> >
> > ---
> >
> > Change-Id: I1f1672652c8392f15f7ca8ac26cd4e71f9cc1e4b
> > ---
> >  include/linux/compiler-clang.h | 8 ++++++++
> >  include/linux/compiler-gcc.h   | 5 +++++
> >  2 files changed, 13 insertions(+)
> >
> > diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h
> > index 333a6695a918..edba13a069a6 100644
> > --- a/include/linux/compiler-clang.h
> > +++ b/include/linux/compiler-clang.h
> > @@ -24,6 +24,14 @@
> >  #define __no_sanitize_address
> >  #endif
> >
> > +/* KMSAN is a Clang-only tool, thus putting the defines here */
>
> I'm not sure if this comment is useful here.

Dropped the comment in v4.