Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756922Ab3DSHW4 (ORCPT ); Fri, 19 Apr 2013 03:22:56 -0400 Received: from mail-ee0-f48.google.com ([74.125.83.48]:58302 "EHLO mail-ee0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756710Ab3DSHWz (ORCPT ); Fri, 19 Apr 2013 03:22:55 -0400 Date: Fri, 19 Apr 2013 09:22:50 +0200 From: Ingo Molnar To: Tejun Heo Cc: Masami Hiramatsu , Ingo Molnar , Linus Torvalds , linux-kernel@vger.kernel.org, "David S. Miller" , Ananth N Mavinakayanahalli , yrl.pp-manager.tt@hitachi.com Subject: Re: [PATCH -tip ] [BUGFIX] kprobes: Fix a double lock bug of kprobe_mutex Message-ID: <20130419072250.GA20897@gmail.com> References: <20130418093318.13070.29847.stgit@mhiramat-M0-7522> <20130418181709.GE9897@mtj.dyndns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130418181709.GE9897@mtj.dyndns.org> 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: 1293 Lines: 34 * Tejun Heo wrote: > On Thu, Apr 18, 2013 at 06:33:18PM +0900, Masami Hiramatsu wrote: > > Fix a double locking bug caused when debug.kprobe-optimization=0. > > While the proc_kprobes_optimization_handler locks kprobe_mutex, > > wait_for_kprobe_optimizer locks it again and that causes a double lock. > > To fix the bug, this introduces different mutex for protecting > > sysctl parameter and locks it in proc_kprobes_optimization_handler. > > Of course, since we need to lock kprobe_mutex when touching kprobes > > resources, that is done in *optimize_all_kprobes(). > > > > This bug was from ad72b3bea744b4db01c89af0f86f3e8920d354df > > > > Signed-off-by: Masami Hiramatsu > > Cc: Ingo Molnar > > Cc: Tejun Heo > > Cc: Ananth N Mavinakayanahalli > > Cc: "David S. Miller" > > Oops, > > Acked-by: Tejun Heo Since you pushed the original commit, mind pushing this fix to Linus too? Thanks, Ingo -- 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/