Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757837Ab3GVRKK (ORCPT ); Mon, 22 Jul 2013 13:10:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45802 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757501Ab3GVRKI (ORCPT ); Mon, 22 Jul 2013 13:10:08 -0400 Date: Mon, 22 Jul 2013 19:04:42 +0200 From: Oleg Nesterov To: Masami Hiramatsu Cc: Steven Rostedt , Peter Zijlstra , Frederic Weisbecker , linux-kernel@vger.kernel.org, Ingo Molnar , Arnaldo Carvalho de Melo , Andrew Morton , jovi.zhangwei@huawei.com, Jiri Olsa , Srikar Dronamraju Subject: Re: [RFC PATCH V2] tracing: Check f_dentry before accessing event_file/call in inode->i_private Message-ID: <20130722170442.GA27002@redhat.com> References: <20130705003223.GA4981@redhat.com> <20130709075519.2583.96462.stgit@mhiramat-M0-7522> <20130715181659.GA18505@redhat.com> <51E5FD33.4040604@hitachi.com> <20130717145148.GB7358@redhat.com> <51E750F4.5070200@hitachi.com> <20130718145137.GA6014@redhat.com> <51E8CCC0.7030404@hitachi.com> <20130719133327.GA21278@redhat.com> <51ED0227.6020204@hitachi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <51ED0227.6020204@hitachi.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1192 Lines: 38 On 07/22, Masami Hiramatsu wrote: > > (2013/07/19 22:33), Oleg Nesterov wrote: > > My only point, imho this is more complex than necessary. > > I see, so I'd like to see the fix. However, I'm not sure > we have enough time to fix that cleanly. I promise, tomorrow I'll re-send the RFC patches, so if you don't like them we can switch back to refcounting. Sorry for delay. Today I was busy with other bugs I "found" in subsystem_open/etc code, but when I tried to fix them I realized that I have misread this code. > Note that except > for the timing bug, we still leave a kernel bug which can > easily be reproduced as Jovi reported. Could you please remind ? > >> OK, let me confirm that, would you mean we still need 2/4 - 4/4? > > > > Yes, yes. > > And those are depends on 1/4... Not at all or I missed something (quite possible). Just 2/4 should not check ->flags, of course. 3/4 looks "obviously fine", 4/4 was already merged. Oleg. -- 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/