On Sat, Apr 09, 2011 at 09:05:41PM +0100, Stefan Hajnoczi wrote:
> On Sat, Apr 9, 2011 at 5:51 PM, Lyu Mitnick <
address@hidden> wrote:
> > Hell all,
> > I have take a look of block/vpc.c and meet a question in vpc_create().?At
> > the line
> > 550, the code is:
> > total_sectors = options->value.n / 512;
> > I am wondering whether the size between?total_sectors * 512
> > and?options->value.n
> > would be discard.
>
> Yes, it rounds down. This reflects the assumption that a block device
> cannot be addressed below 512 byte sectors. Because of this block
> devices size must be a multiple of 512 bytes.
>
> I think a reasonable protection would be to have block.c:bdrv_create()
> fail if size is not a multiple of BDRV_SECTOR_SIZE. This way other
> image formats are protected too.