netdev - Re: [PATCH RFC] tun: export underlying socket

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 15 Sep 2009 01:03:13 +1000
From:	Herbert Xu <herbert@...dor.apana.org.au>
To:	Or Gerlitz <ogerlitz@...taire.com>
Cc:	"Michael S. Tsirkin" <mst@...hat.com>,
	David Miller <davem@...emloft.net>, netdev@...r.kernel.org
Subject: Re: [PATCH RFC] tun: export underlying socket

On Mon, Sep 14, 2009 at 05:06:52PM +0300, Or Gerlitz wrote:
>
>> A lot of people have asked for tun support in vhost, because qemu currently uses tun.  With this scheme existing code and scripts can be used to configure both tun and bridge.  You also can utilize virtualization-specific features in tun.
> Tun has code to support some virtualization-specific features, however,  
> it has also some inherent problems, I think, for example, you don't know  
> over which NIC eventually a packet will be sent and as such, the feature  
> advertising to the guest (virtio-net) NIC is problematic, for example,  
> TSO. With vhost, since you are directly attached to a NIC and assuming  
> its a PF or VF NIC and not something like macvlan/veth you can actually  
> know what features are supported by this NIC.

TSO is not a problem because we provide a software fallback when
the hardware does not support it.  So guests should always enable
TSO if they support it and not worry about the physical NIC.

Cheers,
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@...dor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html