Re: [Qemu-devel] [PATCH 5/6] vhost-net: tell tap backend about the vnet endianness

[Greg Kurz <gkurz@linux.vnet.ibm.com>]

On Fri, 19 Jun 2015 11:16:35 +0200
Thomas Huth <thuth@redhat.com> wrote:

> 
>  Hi,
> 
> On Wed, 17 Jun 2015 15:23:49 +0200
> Greg Kurz <gkurz@linux.vnet.ibm.com> wrote:
> 
> > The default behaviour for TAP/MACVTAP is to consider vnet as native endian.
> > 
> > This patch handles the cases when this is not true:
> > - virtio 1.0: always little-endian
> > - legacy cross-endian
> > 
> > Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
> > ---
> >  hw/net/vhost_net.c |   33 ++++++++++++++++++++++++++++++++-
> >  1 file changed, 32 insertions(+), 1 deletion(-)
> > 
> > diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
> > index 1c55517e3611..8cbb2f618c1c 100644
> > --- a/hw/net/vhost_net.c
> > +++ b/hw/net/vhost_net.c
> ...
> > @@ -365,6 +394,8 @@ void vhost_net_stop(VirtIODevice *dev, NetClientState *ncs,
> >          fflush(stderr);
> >      }
> >      assert(r >= 0);
> > +
> > +    assert(vhost_net_set_vnet_endian(dev, ncs[0].peer, false) >= 0);
> >  }
> 
> Putting the vhost_net_set_vnet_endian() within the assert statement
> looks somewhat wrong to me. assert() gets defined to nothing in case
> NDEBUG is defined, so the call would then simply be dropped.
> I guess you rather want something like this here:
> 
>     r = vhost_net_set_vnet_endian(dev, ncs[0].peer, false);
>     assert(r >= 0);
> 
> ?
> 
>  Thomas
> 

Oops you're right... I'll send a fix.

--
Greg