Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756762AbcJGQWv (ORCPT ); Fri, 7 Oct 2016 12:22:51 -0400 Received: from mail-wm0-f49.google.com ([74.125.82.49]:38238 "EHLO mail-wm0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753234AbcJGQWo (ORCPT ); Fri, 7 Oct 2016 12:22:44 -0400 Date: Fri, 7 Oct 2016 17:22:40 +0100 From: Lorenzo Stoakes To: Linus Torvalds Cc: Rik van Riel , Hugh Dickins , linux-mm , Mel Gorman , tbsaunde@tbsaunde.org, robert@ocallahan.org, Linux Kernel Mailing List , Andrew Morton Subject: Re: [PATCH] mm: check VMA flags to avoid invalid PROT_NONE NUMA balancing Message-ID: <20161007162240.GA14350@lucifer> References: <20160911225425.10388-1-lstoakes@gmail.com> <20160925184731.GA20480@lucifer> <1474842875.17726.38.camel@redhat.com> <20161007100720.GA14859@lucifer> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.7.0 (2016-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 861 Lines: 18 On Fri, Oct 07, 2016 at 08:34:15AM -0700, Linus Torvalds wrote: > Would you be willing to look at doing that kind of purely syntactic, > non-semantic cleanup first? Sure, more than happy to do that! I'll work on a patch for this. > I think that if we end up having the FOLL_FORCE semantics, we're > actually better off having an explicit FOLL_FORCE flag, and *not* do > some kind of implicit "under these magical circumstances we'll force > it anyway". The implicit thing is what we used to do long long ago, we > definitely don't want to. That's a good point, it would definitely be considerably more 'magical', and expanding the conditions to include uprobes etc. would only add to that. I wondered about an alternative parameter/flag but it felt like it was more-or-less FOLL_FORCE in a different form, at which point it may as well remain FOLL_FORCE :)