From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Pirko Subject: Re: HW communication debugging interface - ideas? Date: Tue, 6 Oct 2015 10:14:57 +0200 Message-ID: <20151006081457.GD2165@nanopsycho.orion> References: <20150930135141.GF2098@nanopsycho.orion> <9B0331B6EBBD0E4684FBFAEDA55776F91944E43E@HASMSX110.ger.corp.intel.com> <20151005095633.GE2278@nanopsycho.orion> <20151005144941.GC8673@lunn.ch> <20151005145542.GJ2278@nanopsycho.orion> <20151005145842.GD8673@lunn.ch> <20151005151821.GK2278@nanopsycho.orion> <56129745.1020805@gmail.com> <20151005153554.GM2278@nanopsycho.orion> <56129B7D.4040402@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andrew Lunn , "Rosen, Rami" , "davem@davemloft.net" , "netdev@vger.kernel.org" , "eladr@mellanox.com" , "idosch@mellanox.com" To: John Fastabend Return-path: Received: from mail-wi0-f175.google.com ([209.85.212.175]:37664 "EHLO mail-wi0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750818AbbJFIO7 (ORCPT ); Tue, 6 Oct 2015 04:14:59 -0400 Received: by wicfx3 with SMTP id fx3so147179936wic.0 for ; Tue, 06 Oct 2015 01:14:58 -0700 (PDT) Content-Disposition: inline In-Reply-To: <56129B7D.4040402@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: Mon, Oct 05, 2015 at 05:47:09PM CEST, john.fastabend@gmail.com wrote: >On 15-10-05 08:35 AM, Jiri Pirko wrote: >> Mon, Oct 05, 2015 at 05:29:09PM CEST, john.fastabend@gmail.com wrote: >>> On 15-10-05 08:18 AM, Jiri Pirko wrote: >>>> Mon, Oct 05, 2015 at 04:58:42PM CEST, andrew@lunn.ch wrote: >>>>> On Mon, Oct 05, 2015 at 04:55:42PM +0200, Jiri Pirko wrote: >>>>>> Mon, Oct 05, 2015 at 04:49:41PM CEST, andrew@lunn.ch wrote: >>>>>>>>> Are you referring here to messages of the EMAD protocol ? >>>>>>> >>>>>>> I know nothing about this protocol..... >>>>>>> >>>>>>> Does it at least use standard Ethernet framing? Source and Destination >>>>>>> header and an EtherType which mean EMAD? >>>>>> >>>>>> Yep, but that does not really matter. I believe we should find debugging >>>>>> interface which is protocol agnostic. Just arbitrary messages >>>>>> monitoring. >>>>> >>>>> Hi Jiri >>>>> >>>>> O.K, it is just that you mentioned wireshark. Passing the frames to >>>>> network interface taps would make this trivial. >>>> >>>> That is true. But using netlink+nlmon would do the same. >>> >>> Also I guess if you go this direction you want to make it generic >>> enough for any drivers to use it to snoop software/firmware msgs. This >>> is common across many devices. >> >> Yes, definitelly, this should be something generic to be usable for >> every device type. >> >> >>> >>> In the past though I've just used ethtool dump commands and some >>> "scripts" on top of this to debug devices. And when it got really >>> bad wrote some throw away code to debug my issue. I guess it might >>> be nice to have something in the kernel to improve this but have >>> you considered using the tracing features that already exist? >> >> Which ones do you have in mind? >> > >I was thinking something like kprobes+bpf to dump a trace and >then a lua script in wireshark to parse the input and pretty >print it for users. This might get you good-enough support without >having to carry it around in the kernel just so we can debug >the devices. We could build some libs/pkgs around it in userspace >and get it published somewhere so we can all work on it together. Well, I was thinking rather about some standard interface, not dependent on actual kernel internals. > >I suspect the primary users for this will be developers anyways >and maybe some users who have a real nasty bug. > >> >>> >>> .John >>> >>>> -- >>>> To unsubscribe from this list: send the line "unsubscribe netdev" in >>>> the body of a message to majordomo@vger.kernel.org >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>>> >>> >