From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757599AbcDGUmj (ORCPT ); Thu, 7 Apr 2016 16:42:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37798 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756795AbcDGUmh convert rfc822-to-8bit (ORCPT ); Thu, 7 Apr 2016 16:42:37 -0400 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <1460060518.1800.8.camel@perches.com> References: <1460060518.1800.8.camel@perches.com> <1460049545.6715.98.camel@perches.com> <1460046677.6715.95.camel@perches.com> <20160407162256.21283.47849.stgit@warthog.procyon.org.uk> <20160407162309.21283.11482.stgit@warthog.procyon.org.uk> <24286.1460048722@warthog.procyon.org.uk> <981.1460058224@warthog.procyon.org.uk> To: Joe Perches Cc: dhowells@redhat.com, linux-afs@lists.infradead.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/9] rxrpc: Disable a debugging statement that has been left enabled. MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Date: Thu, 07 Apr 2016 21:42:34 +0100 Message-ID: <5417.1460061754@warthog.procyon.org.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Joe Perches wrote: > > Let's see...  If the machine panics whilst I'm developing stuff (quite > > likely if something goes wrong in BH context), how do I get at the > > function tracing log to find out why it panicked if the log is then > > lost?  With the serial console, at least I automatically capture the > > output of kenter and co.. > > But you also don't get a bunch of other useful stuff. > > btw: there is ftrace_dump_on_oops > > https://lwn.net/Articles/366796/ Cute. How do I get at the argument values and suchlike that kenter() and co print? I presume I would need to replace any kenter() or suchlike that printed more than just the address with a tracing hook? David