Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932729AbXF2CPu (ORCPT ); Thu, 28 Jun 2007 22:15:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1765080AbXF2CPl (ORCPT ); Thu, 28 Jun 2007 22:15:41 -0400 Received: from smtp-out.google.com ([216.239.33.17]:45114 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1765064AbXF2CPl (ORCPT ); Thu, 28 Jun 2007 22:15:41 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=received:date:from:x-x-sender:to:cc:subject:in-reply-to: message-id:references:mime-version:content-type; b=pwlouuFTMa5BdXA4xkUsglGMD5dJ7IyPX5atn+EBG9Adsu+XVGfK4RAZu+S+SchIF 3nY75bLpKomZ5Jy2tRy/Q== Date: Thu, 28 Jun 2007 19:15:14 -0700 (PDT) From: Joshua Wise X-X-Sender: jwise@internets.corp.google.com To: Andrew Morton cc: Kyle McMartin , linux-kernel@vger.kernel.org, thockin@google.com, mikew@google.com, masouds@google.com Subject: Re: [PATCH] [revised -- version 2] Info dump on Oops or panic() In-Reply-To: <20070628164855.012344cd.akpm@linux-foundation.org> Message-ID: References: <20070628221835.GI2784@fattire.cabal.ca> <20070628164855.012344cd.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2189 Lines: 57 On Thu, 28 Jun 2007, Andrew Morton wrote: > Your email client is doing space-stuffing. It's easy enough to fix at this > end, but even easier if you fix it ;) Aw darn :( Stupid PINE. I'll fix it for the next patch. >> + atomic_notifier_call_chain(&info_dumper_list, 0, NULL); [...] > So... Please consider abandoning the notifier-chain and just go for a > simple function call. As we discovered some minutes ago, there appears to be infrastructure for this already -- the die_chain. For thsoe of you who don't know, the die_chain gets called from notify_die. It exists on almost all architectures. On i386, it gets called from die() on arch/i386/kernel/traps.c:417 -- before registers are scrolled by. So, if we want our own specific output there, like utsname or uptime, then we can get it. There exists a DIE_PANIC type on some architectures, but it's never actually ... used. So, I will probably write a patch to add it on all architectures, and use it in the panic routines. >> +ATOMIC_NOTIFIER_HEAD(info_dumper_list); >> +EXPORT_SYMBOL(info_dumper_list); > > That export isn't needed. If I want someone else to access it, like a module, it is... But, I guess if I wanted to act as per canon, I should just do register functions, and export those. On the die_chain, those are EXPORT_SYMBOL_GPL, FWIW > Again, a deref of current->nsproxy->uts_ns->name at oops-time has risks. > > This string could be precalculated, no? Yes, and will be. > I don't know what to do here. It will be hard to find a read-the-time > function which is a) lockless and b) available on all architectures and > configs. > > If you can find a way to use plain old jiffies, that'd be good. jiffies sounds good enough to me. There seems to be some opposition to the utsname and uptime patches. I'll take a look at those here and see what I can do to make those a little more pleasing to non-Google users. Expect a patch for DIE_PANIC tomorrow... joshua - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/