Re: [Qemu-devel] [PATCH] virtio-serial: PCI device for simple host <-> guest communication

[Blue Swirl]

On 6/11/09, Amit Shah <address@hidden> wrote:
> On (Tue) Jun 09 2009 [13:56:57], Anthony Liguori wrote:
>  > Richard W.M. Jones wrote:
>  >> On Tue, Jun 09, 2009 at 10:12:48PM +0530, Amit Shah wrote:
>  >> [...]
>  >>
>  >> Are you going to post the virtio driver for the Linux kernel later?
>  >>
>  >
>  > Yeah, I'd like to see the Linux driver before drawing conclusions.
>
>  Pasting here a slightly older version of the patch. I'm actively working
>  on it; a few things might have changed but the basic idea remains the
>  same.

>  + * along with this program; if not, write to the Free Software
>  + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

Old FSF address, the new one is on Franklin St.

>  +struct virtio_serial_port {

>  +       unsigned int read_len;

This limits the maximum transfer length to 4G, which is way too short
on 64 bit hosts. ;-)

>  +struct virtio_serial_config {
>  +       __u8 nr_ports;
>  +       __u16 status;
>  +} __attribute__((packed));

The structure should be redesigned to work without packed attribute.
status field is unaligned.