From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:41203)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <benoit.canet@irqsave.net>) id 1WjrNN-0006Lv-JN
	for qemu-devel@nongnu.org; Mon, 12 May 2014 10:38:51 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <benoit.canet@irqsave.net>) id 1WjrNH-0000YF-9O
	for qemu-devel@nongnu.org; Mon, 12 May 2014 10:38:45 -0400
Received: from lputeaux-656-01-25-125.w80-12.abo.wanadoo.fr
	([80.12.84.125]:47743 helo=paradis.irqsave.net)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <benoit.canet@irqsave.net>) id 1WjrNH-0000Xy-47
	for qemu-devel@nongnu.org; Mon, 12 May 2014 10:38:39 -0400
Date: Mon, 12 May 2014 16:39:12 +0200
From: =?iso-8859-1?Q?Beno=EEt?= Canet <benoit.canet@irqsave.net>
Message-ID: <20140512143911.GD7858@irqsave.net>
References: <1399899851-5641-1-git-send-email-kwolf@redhat.com>
	<1399899851-5641-2-git-send-email-kwolf@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
In-Reply-To: <1399899851-5641-2-git-send-email-kwolf@redhat.com>
Content-Transfer-Encoding: quoted-printable
Subject: Re: [Qemu-devel] [PATCH 1/5] qcow1: Make padding in the header
 explicit
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-devel@nongnu.org, stefanha@redhat.com, ppandit@redhat.com

The Monday 12 May 2014 =E0 15:04:07 (+0200), Kevin Wolf wrote :
> We were relying on all compilers inserting the same padding in the
> header struct that is used for the on-disk format. Let's not do that.
> Mark the struct as packed and insert an explicit padding field for
> compatibility.
>=20
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>  block/qcow.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>=20
> diff --git a/block/qcow.c b/block/qcow.c
> index 937dd6d..3684794 100644
> --- a/block/qcow.c
> +++ b/block/qcow.c
> @@ -48,9 +48,10 @@ typedef struct QCowHeader {
>      uint64_t size; /* in bytes */
>      uint8_t cluster_bits;
>      uint8_t l2_bits;
> +    uint16_t padding;
>      uint32_t crypt_method;
>      uint64_t l1_table_offset;
> -} QCowHeader;
> +} QEMU_PACKED QCowHeader;
> =20
>  #define L2_CACHE_SIZE 16
> =20
> --=20
> 1.8.3.1
>=20
>=20
Reviewed-by: Benoit Canet <benoit@irqsave.net>