| |
|
 |
|
 |
|
|
|
| |
|
|
xen-devel
[Xen-devel] Re: SKB paged fragment lifecycle on receive
On Mon, 2011-06-27 at 23:49 +0100, David Miller wrote:
> From: Ian Campbell <Ian.Campbell@xxxxxxxxxxxxx>
> Date: Mon, 27 Jun 2011 15:42:04 +0100
>
> > However it seems like this might still have a problem if your SKBs are
> > ever cloned. What happens in this case, e.g if a user of AF_PACKET sends
> > a broadcast via a device associated with a bridge[1] (where it would be
> > flooded)?
>
> You don't need a bridge to get a clone on transmit, the packet
> scheduler can do clones. Just grep for skb_clone in the packet
> action handlers net/sched/act_*.c
Are you sure? I only see skb_cloned() and skb_clone_writeable() under
there )(3.0-rc4) and not any actual skb_clone()s.
The only actual clone I see under there is in net/sched/sch_netem.c.
However it sounds like it is expected that a clone can happen on pretty
any skb which makes the frag lifecycle issue seem like one which could
effect anything which sends a page to the network without relinquishing
complete control of it (common in any kind of zero-copy scenario).
Ian.
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
|
|
| |
|
Home