[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-Id: <1249016117.19210.2.camel@maxim-laptop>
Date: Fri, 31 Jul 2009 07:55:17 +0300
From: Maxim Levitsky <maximlevitsky@...il.com>
To: Jason Wessel <jason.wessel@...driver.com>
Cc: Jun Koi <junkoi2004@...il.com>, linux-kernel@...r.kernel.org,
Bernhard Kaindl <bk@...e.de>,
KGDB Mailing List <kgdb-bugreport@...ts.sourceforge.net>
Subject: Re: Firewire debugging tools - firedump & fireproxy?
On Thu, 2009-07-30 at 16:10 -0500, Jason Wessel wrote:
> Maxim Levitsky wrote:
> > On Thu, 2009-07-30 at 03:31 -0500, Jason Wessel wrote:
> >>
> >> 3) Develop a low level dedicated ethernet debug interface. If you have
> >> more than one ethernet, or an ethernet device that has multiple hardware
> >> queues, it is plausible to have a dedicated way to talk to a device
> >> which has no restrictions on getting preempted, or used by another part
> >> of the kernel. This lends itself to an ideal medium for kgdb
> >> communications.
>
> > Or, even better, to make in possible to switch between a normal, and
> > exclusive mode? Maybe this cab be done without (or with slight)
> > modifications to network drivers. Why not to make kgdb own the
> > network device (use it exclusively), but use same interfaces as
> > regular kernel does?
>
> The key problem is how such a switch is governed between normal and
> exclusive mode works. If it involves locks kgdboe is not going to
> work reliably from the exception context.
I mean the switch should happen just once, when kgdboe is loaded, and
back when unloaded.
>
> Having kgdboe directly own an interface and use the same kernel API as
> the network stack won't work out of the box because there is probing,
> interrupt control and lots of other tidbits. This is a case where the
> polling API needs some work or a dedicated API is needed, because this
> is a case where you really don't want the whole network stack
> involved. IE it would be nice to be able to debug the networking
> stack with kgdboe.
Sure, but I feel that doing any significant changes to _all_ ethernet
drivers is a huge job.
>
> Patches which implement new functionality, ideas and discussion about
> any aspect of kernel debugging are always welcome on the kgdb mailing
> list. :-)
Best regards,
Maxim Levitsky
>
> Cheers,
> Jason.
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists