From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Graf <tgraf@suug.ch>
Subject: Re: [patch net-next v2 8/9] switchdev: introduce Netlink API
Date: Tue, 23 Sep 2014 08:19:22 +0100
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Cc: Tom Herbert <therbert@google.com>,
	Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	Jiri Pirko <jiri@resnulli.us>,
	John Fastabend <john.r.fastabend@intel.com>,
	Jamal Hadi Salim <jhs@mojatatu.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
	Neil Horman <nhorman@tuxdriver.com>,
	Andy Gospodarek <andy@greyhouse.net>,
	Daniel Borkmann <dborkman@redhat.com>,
	Or Gerlitz <ogerlitz@mellanox.com>,
	Jesse Gross <jesse@nicira.com>,
	Pravin Shelar <pshelar@nicira.com>,
	Andy Zhou <azhou@nicira.com>,
	Ben Hutchings <ben@decadent.org.uk>,
	Stephen Hemminger <stephen@networkplumber.org>,
	Jeff Kirsher <jeffrey.t.kirsher@intel.com>,
	Vladislav Yasevich <vyasevic@redhat.com>,
	Cong Wang <xiyou.wangcong@gmail.com>,
	Eric Dumazet <edumazet@google.com>,
	Scott Feldman <sfeldma@cumulusnetworks.com>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Roop
To: John Fastabend <john.fastabend@gmail.com>
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On 09/22/14 at 06:36pm, John Fastabend wrote:
> n-tuple has some deficiencies,
> 
> 	- its not possible to get the capabilities to learn what
> 	  fields are supported by the device, what actions, etc.
> 
> 	- its ioctl based so we have to poll the device
> 
> 	- only supports a single table, where we have devices with
> 	  multiple tables
> 
> 	- sort of the same as above but it doesn't allow creating new
> 	  tables or destroying old tables.

OK, I understand where Tom was going. Given we add feature detection
capabilities this could be used to identify the guest for fixed length
encap. I still assume HW won't be able to match on the inner header
for any variable lengh encap with metadata packet unless it can
actually parse the encap. I hope I didn't bring encap format to this
thread at this very moment ;-)