From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752802AbZLVBNr (ORCPT ); Mon, 21 Dec 2009 20:13:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752402AbZLVBNp (ORCPT ); Mon, 21 Dec 2009 20:13:45 -0500 Received: from mx1.redhat.com ([209.132.183.28]:65084 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751381AbZLVBNp (ORCPT ); Mon, 21 Dec 2009 20:13:45 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Roland McGrath To: Oleg Nesterov X-Fcc: ~/Mail/linus Cc: Andi Kleen , linux-kernel@vger.kernel.org, torvalds@linux-foundation.org Subject: Re: BKL use in ptrace In-Reply-To: Oleg Nesterov's message of Monday, 21 December 2009 18:02:37 +0100 <20091221170237.GA5384@redhat.com> References: <20091220185318.GA15989@basil.fritz.box> <20091221170237.GA5384@redhat.com> X-Antipastobozoticataclysm: When George Bush projectile vomits antipasto on the Japanese. Message-Id: <20091222011329.D78C010274@magilla.sf.frob.com> Date: Mon, 21 Dec 2009 17:13:29 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > I never understood this lock_kernel(). > > In any case it looks outdated. We were going to kill it "soon", > along with other ptrace changes. I never understood it either. It's very ancient and long predates many, many ptrace cleanups. If the comment was ever accurate, then any issue like that is now covered by cred_guard_mutex. I don't know of any reason for (or really, effect of) using BKL in ptrace. Thanks, Roland