>>> On 11/9/2011 at 08:58 AM, in message <4ebaa30d.1090...@redhat.com>, Kevin
>>> Wolf
<kw...@redhat.com> wrote:
>
> Right, I'm not arguing that your change is wrong. What I'm asking for is
> just something like:
>
> - dyndisk_header->data_offset = be64_to_cpu(0xFFFFFFFF);
> + /* Note: The spec is actually wrong here, it says 0xFFFFFFFF, but
> MS tools expect all 64 bits to be set */
> + dyndisk_header->data_offset = be64_to_cpu(0xFFFFFFFFFFFFFFFFULL);
>
> Kevin
Ok, I had the header comment on the brain, not a code comment.
Here is the revised patch.
- Charles
The Data Offset field in the Dynamic Disk Header is an 8 byte field.
Although the specification (2006-10-11) gives an example of initializing
only the first 4 bytes, images generated by Microsoft on Windows initialize
all 8 bytes.
Failure to initialize all 8 bytes results in errors from utilities
like Citrix's vhd-util which checks specifically for the proper Data
Offset field initialization.
Signed-off-by: Charles Arnold <carn...@suse.com>
diff --git a/block/vpc.c b/block/vpc.c
index 416f489..179c6ae 100644
--- a/block/vpc.c
+++ b/block/vpc.c
@@ -585,7 +585,11 @@ static int vpc_create(const char *filename,
QEMUOptionParameter *options)
memcpy(dyndisk_header->magic, "cxsparse", 8);
- dyndisk_header->data_offset = be64_to_cpu(0xFFFFFFFF);
+ /*
+ * Note: The spec is actually wrong here for data_offset, it says
+ * 0xFFFFFFFF, but MS tools expect all 64 bits to be set.
+ */
+ dyndisk_header->data_offset = be64_to_cpu(0xFFFFFFFFFFFFFFFFULL);
dyndisk_header->table_offset = be64_to_cpu(3 * 512);
dyndisk_header->version = be32_to_cpu(0x00010000);
dyndisk_header->block_size = be32_to_cpu(block_size);
