Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966627AbcKOKTL (ORCPT ); Tue, 15 Nov 2016 05:19:11 -0500 Received: from mail-wm0-f68.google.com ([74.125.82.68]:34189 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966082AbcKOKTH (ORCPT ); Tue, 15 Nov 2016 05:19:07 -0500 Date: Tue, 15 Nov 2016 11:19:03 +0100 From: Ingo Molnar To: Borislav Petkov Cc: X86 ML , LKML , Andy Lutomirski , Linus Torvalds , Peter Zijlstra Subject: Re: [RFC PATCH] x86/debug: Dump more detailed segfault info Message-ID: <20161115101903.GA15249@gmail.com> References: <20161111101930.32559-1-bp@alien8.de> <20161112110649.GA28774@gmail.com> <20161112122736.fmiowshbus5hjjnb@pd.tnic> <20161113073903.GA648@gmail.com> <20161113112552.ci5hkct4d4xm6rrf@pd.tnic> <20161113154958.w4pkp4nvyyau4u6z@pd.tnic> <20161115061447.GA24505@gmail.com> <20161115100655.flju5ce3zxtrcyx4@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161115100655.flju5ce3zxtrcyx4@pd.tnic> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 763 Lines: 22 * Borislav Petkov wrote: > On Tue, Nov 15, 2016 at 07:14:47AM +0100, Ingo Molnar wrote: > > So I think the line breaking artifact might be due to the following commit: > > > > bfd8d3f23b51 ("printk: make reading the kernel log flush pending lines") > > > > ... which Linus reverted upstream a few hours ago: > > Probably. I guess this doesn't happen when running my guest here because > I have the segfault logging change ontop of -rc4. Well, bfd8d3f23b51 was part of -rc1 already, so you have it too. What might have made the difference is that I tested it on real hardware with serial logging, which delays printk() and might have created the race with the systemd kernel logger. (Which is impossible to turn off :-( ) Thanks, Ingo