Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755632Ab3I3QvI (ORCPT ); Mon, 30 Sep 2013 12:51:08 -0400 Received: from mail-wg0-f53.google.com ([74.125.82.53]:62077 "EHLO mail-wg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754561Ab3I3QvG (ORCPT ); Mon, 30 Sep 2013 12:51:06 -0400 Date: Mon, 30 Sep 2013 18:51:01 +0200 From: Frederic Weisbecker To: Linus Torvalds Cc: Ingo Molnar , Thomas Gleixner , LKML , Benjamin Herrenschmidt , "#3.9.." , Paul Mackerras , Peter Zijlstra , "H. Peter Anvin" , James Hogan , "James E.J. Bottomley" , Helge Deller , Martin Schwidefsky , Heiko Carstens , "David S. Miller" , Andrew Morton Subject: Re: [GIT PULL] irq fix for 3.12-rc Message-ID: <20130930165059.GA9889@localhost.localdomain> References: <1380552959-9396-1-git-send-email-fweisbec@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3008 Lines: 54 On Mon, Sep 30, 2013 at 09:07:19AM -0700, Linus Torvalds wrote: > On Mon, Sep 30, 2013 at 7:55 AM, Frederic Weisbecker wrote: > > ... > > the chances for a stack overrun as reported in powerpc for example: > > > > [ 1002.364577] do_IRQ: stack overflow: 1920 > > [ 1002.364653] CPU: 0 PID: 1602 Comm: qemu-system-ppc Not tainted 3.10.4-300.1.fc19.ppc64p7 #1 > > [ 1002.364734] Call Trace: > > [ 1002.364770] [c0000000050a8740] [c0000000000157c0] .show_stack+0x130/0x200 (unreliable) > > [ 1002.364872] [c0000000050a8810] [c00000000082f6d0] .dump_stack+0x28/0x3c > > [ 1002.364955] [c0000000050a8880] [c000000000010b98] .do_IRQ+0x2b8/0x2c0 > > [ 1002.365039] [c0000000050a8930] [c0000000000026d4] hardware_interrupt_common+0x154/0x180 > > [ 1002.365148] --- Exception: 501 at .cp_start_xmit+0x3a4/0x820 [8139cp] > > [ 1002.365148] LR = .cp_start_xmit+0x390/0x820 [8139cp] > > [ 1002.365359] [c0000000050a8d40] [c0000000006d7f14] .dev_hard_start_xmit+0x394/0x640 > > ... > > Btw, I'd really wish people edited things like this when putting them > in the commit logs. I try to do it when I get them (usually though > Andrew's patch-bombs), just because there's just a ton of detail there > that just isn't relevant for the actual issue at hand. > > The kernel oops messages try to contain all kinds of possibly-relevant > data, which makes them useful for a wide range of situations ("oh, it > looks like a single-bit flip"), but at the same time means that once > you know what the problem is, 90% of the data printed out is just pure > noise and at that point no longer helpful, but just makes it harder to > see what's actually the issue. > > So please, after you've analyzed an oops, don't use the raw oops data > any more. Usually what remains relevant is the actual oops message > itself, and the backtrace.I try to generally edit out the hex > representation of the symbol information, and obviously stale entries > from the backtrace. I'm not consistent, see for example commit > 6f6b8951897e (register info remains) vs commit d6394b590029 (mainly > just call trace) vs commit 3e6b11df2451 (where I just truncated it > mercilessly). And no, I don't always clean things up (it can be a > bother), but I generally try, so now I'm just trying to spread the > word.. > > Because at some point the excess verbiage really goes from "that's > useful" to being a blob of noise that actually takes away from the > message. Yeah, I did such things sporadically before. Well, it summed up to simply remove the timestamps from backtraces but yeah, then I've become less patient about that and now I simply paste the raw thing. I'll take care of that and prune these things on my future patches. -- 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/