From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756119AbbAXB0L (ORCPT ); Fri, 23 Jan 2015 20:26:11 -0500 Received: from mail-lb0-f181.google.com ([209.85.217.181]:49063 "EHLO mail-lb0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751737AbbAXB0I (ORCPT ); Fri, 23 Jan 2015 20:26:08 -0500 MIME-Version: 1.0 In-Reply-To: <54C2B396.9090106@oracle.com> References: <7665538633a500255d7da9ca5985547f6a2aa191.1416604491.git.luto@amacapital.net> <54C17139.1040706@oracle.com> <20150123180455.GA3192@pd.tnic> <54C2B396.9090106@oracle.com> From: Andy Lutomirski Date: Fri, 23 Jan 2015 17:25:45 -0800 Message-ID: Subject: Re: [PATCH v4 2/5] x86, traps: Track entry into and exit from IST context To: Sasha Levin Cc: Borislav Petkov , X86 ML , Linus Torvalds , "linux-kernel@vger.kernel.org" , Peter Zijlstra , Oleg Nesterov , Tony Luck , Andi Kleen , "Paul E. McKenney" , Josh Triplett , =?UTF-8?B?RnLDqWTDqXJpYyBXZWlzYmVja2Vy?= Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 23, 2015 at 12:48 PM, Sasha Levin wrote: > On 01/23/2015 01:34 PM, Andy Lutomirski wrote: >> On Fri, Jan 23, 2015 at 10:04 AM, Borislav Petkov wrote: >>> On Fri, Jan 23, 2015 at 09:58:01AM -0800, Andy Lutomirski wrote: >>>>> [ 543.999079] Call Trace: >>>>> [ 543.999079] dump_stack (lib/dump_stack.c:52) >>>>> [ 543.999079] lockdep_rcu_suspicious (kernel/locking/lockdep.c:4259) >>>>> [ 543.999079] atomic_notifier_call_chain (include/linux/rcupdate.h:892 kernel/notifier.c:182 kernel/notifier.c:193) >>>>> [ 543.999079] ? atomic_notifier_call_chain (kernel/notifier.c:192) >>>>> [ 543.999079] notify_die (kernel/notifier.c:538) >>>>> [ 543.999079] ? atomic_notifier_call_chain (kernel/notifier.c:538) >>>>> [ 543.999079] ? debug_smp_processor_id (lib/smp_processor_id.c:57) >>>>> [ 543.999079] do_debug (arch/x86/kernel/traps.c:652) >>>>> [ 543.999079] ? trace_hardirqs_on (kernel/locking/lockdep.c:2609) >>>>> [ 543.999079] ? do_int3 (arch/x86/kernel/traps.c:610) >>>>> [ 543.999079] ? trace_hardirqs_on_caller (kernel/locking/lockdep.c:2554 kernel/locking/lockdep.c:2601) >>>>> [ 543.999079] debug (arch/x86/kernel/entry_64.S:1310) >>>> >>>> I don't know how to read this stack trace. Are we in do_int3, >>>> do_debug, or both? I didn't change do_debug at all. >>> >>> It looks like we're in do_debug. do_int3 is only on the stack but not >>> part of the current frame if I can trust the '?' ... >>> >> >> It's possible that an int3 happened and I did something wrong on >> return that caused a subsequent do_debug to screw up, but I don't see >> how my patch would have caused that. >> >> Were there any earlier log messages? > > Nope, nothing odd before or after. Trinity just survived for a decent amount of time for me with my patches, other than a bunch of apparently expected OOM kills. I have no idea how to tell trinity how much memory to use. --Andy