Re: [PATCH v5 29/38] kmsan: enable KMSAN builds

From: Andrey Konovalov <andreyknvl@google.com>
To: Alexander Potapenko <glider@google.com>
Cc: Jens Axboe <axboe@kernel.dk>, Andy Lutomirski <luto@kernel.org>,
	 Vegard Nossum <vegard.nossum@oracle.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	 Marco Elver <elver@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>,
	 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>,
	 Marek Szyprowski <m.szyprowski@samsung.com>,
	Mark Rutland <mark.rutland@arm.com>,
	 "Martin K. Petersen" <martin.petersen@oracle.com>,
	Martin Schwidefsky <schwidefsky@de.ibm.com>,
	 Matthew Wilcox <willy@infradead.org>,
	"Michael S . Tsirkin" <mst@redhat.com>,
	Michal Hocko <mhocko@suse.com>,  Michal Simek <monstr@monstr.eu>,
	Petr Mladek <pmladek@suse.com>, Qian Cai <cai@lca.pw>,
	 Randy Dunlap <rdunlap@infradead.org>,
	Robin Murphy <robin.murphy@arm.com>,
	 Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	 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 v5 29/38] kmsan: enable KMSAN builds
Date: Tue, 14 Apr 2020 16:56:13 +0200	[thread overview]
Message-ID: <CAAeHK+xaTy8dcV9JqiQD=5D3s07ZRLA27gAxY80VuGU246fd1g@mail.gmail.com> (raw)
In-Reply-To: <20200325161249.55095-30-glider@google.com>

On Wed, Mar 25, 2020 at 5:14 PM <glider@google.com> wrote:
>
> Make KMSAN usable by adding the necessary Makefile bits.
>
> Signed-off-by: Alexander Potapenko <glider@google.com>
> To: Alexander Potapenko <glider@google.com>
> Cc: Jens Axboe <axboe@kernel.dk>
> Cc: Andy Lutomirski <luto@kernel.org>
> Cc: Vegard Nossum <vegard.nossum@oracle.com>
> Cc: Dmitry Vyukov <dvyukov@google.com>
> Cc: Marco Elver <elver@google.com>
> Cc: Andrey Konovalov <andreyknvl@google.com>
> Cc: linux-mm@kvack.org
>
> ---
> This patch was previously called "kmsan: Changing existing files to
> enable KMSAN builds". Logically unrelated parts of it were split away.
>
> v4:
>  - split away changes to init/main.c as requested by Andrey Konovalov

Hm, I've forgotten what exactly I asked here :(

But right now this patch looks like parts of other patches.

>
> Change-Id: I37e0b7f2d2f2b0aeac5753ff9d6b411485fc374e
> ---
>  Makefile             | 3 ++-
>  mm/Makefile          | 1 +
>  scripts/Makefile.lib | 6 ++++++
>  3 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/Makefile b/Makefile
> index a532333b4cd02..da315f20618b3 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -482,7 +482,7 @@ export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
>
>  export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
>  export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
> -export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN CFLAGS_KCSAN
> +export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN CFLAGS_KCSAN CFLAGS_KMSAN
>  export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
>  export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
>  export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
> @@ -901,6 +901,7 @@ KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
>  endif
>
>  include scripts/Makefile.kasan
> +include scripts/Makefile.kmsan

I think this change should go together with the addition of
scripts/Makefile.kmsan.

>  include scripts/Makefile.extrawarn
>  include scripts/Makefile.ubsan
>  include scripts/Makefile.kcsan
> diff --git a/mm/Makefile b/mm/Makefile
> index fa91e963c2f9e..7b9bce9cc0afb 100644
> --- a/mm/Makefile
> +++ b/mm/Makefile
> @@ -81,6 +81,7 @@ obj-$(CONFIG_PAGE_POISONING) += page_poison.o
>  obj-$(CONFIG_SLAB) += slab.o
>  obj-$(CONFIG_SLUB) += slub.o
>  obj-$(CONFIG_KASAN)    += kasan/
> +obj-$(CONFIG_KMSAN)    += kmsan/

And this change should go together with the addition or enabling of
CONFIG_KMSAN.

>  obj-$(CONFIG_FAILSLAB) += failslab.o
>  obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o
>  obj-$(CONFIG_MEMTEST)          += memtest.o
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index b12dd5ba48960..e9a8c2671a4b3 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -137,6 +137,12 @@ _c_flags += $(if $(patsubst n%,, \
>                 $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
>  endif
>
> +ifeq ($(CONFIG_KMSAN),y)
> +_c_flags += $(if $(patsubst n%,, \
> +               $(KMSAN_SANITIZE_$(basetarget).o)$(KMSAN_SANITIZE)y), \
> +               $(CFLAGS_KMSAN))
> +endif
> +

And this looks like it deserves to be together with the definition of
CFLAGS_KMSAN.

>  ifeq ($(CONFIG_UBSAN),y)
>  _c_flags += $(if $(patsubst n%,, \
>                 $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \
> --
> 2.25.1.696.g5e7596f4ac-goog
>