From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34678) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cAbRW-0001f9-BC for qemu-devel@nongnu.org; Sat, 26 Nov 2016 06:46:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cAbRV-0001x4-Fh for qemu-devel@nongnu.org; Sat, 26 Nov 2016 06:46:54 -0500 Date: Sat, 26 Nov 2016 19:46:41 +0800 From: Fam Zheng Message-ID: <20161126114641.GA17431@lemon.cpc> References: <20161126054650.4486-1-haoqf@linux.vnet.ibm.com> <20161126054650.4486-2-haoqf@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161126054650.4486-2-haoqf@linux.vnet.ibm.com> Subject: Re: [Qemu-devel] [Qemu-stable] [PATCH v2 1/1] block/vmdk: Fix the endian problem of buf_len and lba List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: QingFeng Hao Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org, kwolf@redhat.com, liujbjl@linux.vnet.ibm.com, qemu-stable@nongnu.org, borntraeger@de.ibm.com, cornelia.huck@de.ibm.com On Sat, 11/26 06:46, QingFeng Hao wrote: > The problem was triggered by qemu-iotests case 055. It failed when it > was comparing the compressed vmdk image with original test.img. > > The cause is that buf_len in vmdk_write_extent wasn't converted to > little-endian before it was stored to disk. But later vmdk_read_extent > read it and converted it from little-endian to cpu endian. > If the cpu is big-endian like s390, the problem will happen and > the data length read by vmdk_read_extent will become invalid! > The fix is to add the conversion in vmdk_write_extent, meanwhile, > repair the endianness problem of lba field which shall also be converted > to little-endian before storing to disk. > > Cc: qemu-stable@nongnu.org > Signed-off-by: QingFeng Hao > Signed-off-by: Jing Liu > Signed-off-by: Kevin Wolf > --- > block/vmdk.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/block/vmdk.c b/block/vmdk.c > index a11c27a..26e5f95 100644 > --- a/block/vmdk.c > +++ b/block/vmdk.c > @@ -1354,8 +1354,8 @@ static int vmdk_write_extent(VmdkExtent *extent, int64_t cluster_offset, > goto out; > } > > - data->lba = offset >> BDRV_SECTOR_BITS; > - data->size = buf_len; > + data->lba = cpu_to_le64(offset >> BDRV_SECTOR_BITS); > + data->size = cpu_to_le32(buf_len); > > n_bytes = buf_len + sizeof(VmdkGrainMarker); > iov = (struct iovec) { > -- > 2.8.4 > > Reviewed-by: Fam Zheng