From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755516AbZERPty (ORCPT ); Mon, 18 May 2009 11:49:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751961AbZERPtr (ORCPT ); Mon, 18 May 2009 11:49:47 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:36715 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751422AbZERPtq (ORCPT ); Mon, 18 May 2009 11:49:46 -0400 Date: Mon, 18 May 2009 08:48:50 -0700 (PDT) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: Ingo Molnar cc: linux-kernel@vger.kernel.org, Andrew Morton , Thomas Gleixner , Peter Zijlstra Subject: Re: [GIT PULL] core kernel fixes In-Reply-To: <20090518142301.GA22765@elte.hu> Message-ID: References: <20090518142301.GA22765@elte.hu> User-Agent: Alpine 2.01 (LFD 1184 2008-12-16) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 18 May 2009, Ingo Molnar wrote: > > Thomas Gleixner (1): > futex: futex mapping needs to be writable I do not believe this is right. Just a few lines later, we have: * NOTE: When userspace waits on a MAP_SHARED mapping, even if * it's a read-only handle, it's expected that futexes attach to * the object not the particular process. note how we are _supposed_ to be able to wait for something that is read-only. As such, asking for a writable page is bogus. I'm not going to pull this. I can well imagine that there was a real bug, but this is _not_ the real fix. The commentary is also TOTAL CRAP as far as I can tell. It starts out with: commit 734b05b10e51d4ba38c8fc3ee02e846aab09eedf (futex: use fast_gup()) calls get_user_pages_fast() with the write argument set to 0. This went unnoticed [...] and that is pure and utter SHIT. The fact is, the write argument was ALWAYS zero, and commit 734b05b10e51d4ba38c8fc3ee02e846aab09eedf has nothing to do with anything what-so-ever, and nothing went unnoticed anywhere. The real bug was apparently just commit e4dc5b7a3 ("clean up"). I also have to object to the "Impact" line of that commit. That line is nonsensical and stupid. I hate to bring up this discussion again, but dammit, if those Impact lines are crap, then they are crap and should not be there! The fact that they _look_ nicer and do not break up the story any more doesn't change that fact. If you cannot write sane and meaningful impact lines, then f*ck me with a spoon - JUST DON'T DO THEM! I'm upset. Quite frankly, there are just _so_ many things wrong with that commit that I get angry when it is sent this late in the game. Linus