[Qemu-devel] Re: [PATCH 1/1] qemu-kvm: virtio-net: Re-instate GSO code removed upstream

[Qemu-devel] Re: [PATCH 1/1] qemu-kvm: virtio-net: Re-instate GSO code removed upstream

[Christoph Hellwig]

I might sound like a broken record, but why isn't the full GSO support
for virtio-net upstream in qemu?

[Qemu-devel] Re: [PATCH 1/1] qemu-kvm: virtio-net: Re-instate GSO code removed upstream

[Avi Kivity]

On 09/30/2009 03:51 PM, Christoph Hellwig wrote:
> I might sound like a broken record, but why isn't the full GSO support
> for virtio-net upstream in qemu?
>    

IIRC the current hacks are not upstream quality.

The problem (again IIRC) is that the guest and host negotiate a 
protocol, but the qemu vlan model doesn't have a guest and a host, it 
has peers (possibly more than two), so a lot of translation has to take 
place if you have one peer supporting a guest feature and another not.

IMO the best way out is to drop the vlan model.  It has its uses, but 
they can all be implemented in other ways, and are all have minor usage 
compared to the business of getting data into and out of a guest.

-- 
error compiling committee.c: too many arguments to function

[Qemu-devel] Re: [PATCH 1/1] qemu-kvm: virtio-net: Re-instate GSO code removed upstream

[Mark McLoughlin]

On Wed, 2009-09-30 at 15:55 +0200, Avi Kivity wrote:
> On 09/30/2009 03:51 PM, Christoph Hellwig wrote:
> > I might sound like a broken record, but why isn't the full GSO support
> > for virtio-net upstream in qemu?
> >    
> 
> IIRC the current hacks are not upstream quality.
> 
> The problem (again IIRC) is that the guest and host negotiate a 
> protocol, but the qemu vlan model doesn't have a guest and a host, it 
> has peers (possibly more than two), so a lot of translation has to take 
> place if you have one peer supporting a guest feature and another not.

Right.

> IMO the best way out is to drop the vlan model.  It has its uses, but 
> they can all be implemented in other ways, and are all have minor usage 
> compared to the business of getting data into and out of a guest.

I think we should keep the vlan stuff, just de-emphasise it.

I'm planning on adding -hostnet and -nic arguments, which would not use
vlans by default but rather connect the nic directly to the host side.

The QemuOpts conversion of -net which is waiting to be merged is the
first stage of that.

Cheers,
Mark.

[Qemu-devel] Re: [PATCH 1/1] qemu-kvm: virtio-net: Re-instate GSO code removed upstream

[Gerd Hoffmann]

On 09/30/09 15:59, Mark McLoughlin wrote:
> I'm planning on adding -hostnet and -nic arguments, which would not use
> vlans by default but rather connect the nic directly to the host side.

No new -nic argument please.  We should just finalize the qdev-ifycation 
of the nic drivers, then you'll do either

   -device e1000,vlan=<nr>

or

   -device e1000,hostnet=<name>

and be done with it.

cheers,
   Gerd

Re: [Qemu-devel] Re: [PATCH 1/1] qemu-kvm: virtio-net: Re-instate GSO code removed upstream

[Mark McLoughlin]

On Wed, 2009-09-30 at 21:15 +0200, Gerd Hoffmann wrote:
> On 09/30/09 15:59, Mark McLoughlin wrote:
> > I'm planning on adding -hostnet and -nic arguments, which would not use
> > vlans by default but rather connect the nic directly to the host side.
> 
> No new -nic argument please.  We should just finalize the qdev-ifycation 
> of the nic drivers, then you'll do either
> 
>    -device e1000,vlan=<nr>
> 
> or
> 
>    -device e1000,hostnet=<name>
> 
> and be done with it.

Yeah, that makes sense.

Cheers,
Mark.

[Qemu-devel] Re: [PATCH 1/1] qemu-kvm: virtio-net: Re-instate GSO code removed upstream

[Avi Kivity]

On 09/30/2009 03:59 PM, Mark McLoughlin wrote:
> I think we should keep the vlan stuff, just de-emphasise it.
>    

Maybe we should do what X.org does, break it silently and remove it some 
time later when no one complains.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.

[Qemu-devel] Re: [PATCH 1/1] qemu-kvm: virtio-net: Re-instate GSO code removed upstream

[Mark McLoughlin]

On Thu, 2009-10-01 at 18:49 +0200, Avi Kivity wrote:
> On 09/30/2009 03:59 PM, Mark McLoughlin wrote:
> > I think we should keep the vlan stuff, just de-emphasise it.
> >    
> 
> Maybe we should do what X.org does, break it silently and remove it some 
> time later when no one complains.

Well, the 'silently' part isn't going to work now, is it?

Anyway, I'm sure at least Jan would notice if his 'dump' backend stopped
working

Cheers,
Mark.

[Qemu-devel] Re: [PATCH 1/1] qemu-kvm: virtio-net: Re-instate GSO code removed upstream

[Avi Kivity]

On 10/01/2009 07:00 PM, Mark McLoughlin wrote:
> On Thu, 2009-10-01 at 18:49 +0200, Avi Kivity wrote:
>    
>> On 09/30/2009 03:59 PM, Mark McLoughlin wrote:
>>      
>>> I think we should keep the vlan stuff, just de-emphasise it.
>>>
>>>        
>> Maybe we should do what X.org does, break it silently and remove it some
>> time later when no one complains.
>>      
> Well, the 'silently' part isn't going to work now, is it?
>    

Me and my big mouth.

> Anyway, I'm sure at least Jan would notice if his 'dump' backend stopped
> working
>    

Patch it to use libpcap?

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.