Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935150AbdIYMgZ (ORCPT ); Mon, 25 Sep 2017 08:36:25 -0400 Received: from mx2.suse.de ([195.135.220.15]:46001 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S934745AbdIYMgX (ORCPT ); Mon, 25 Sep 2017 08:36:23 -0400 Date: Mon, 25 Sep 2017 14:36:21 +0200 From: Michal Hocko To: "Michael Kerrisk (man-pages)" Cc: Mike Kravetz , linux-man@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Jann Horn , Florian Weimer , Andrea Arcangeli , "Kirill A . Shutemov" , Vlastimil Babka , Anshuman Khandual Subject: Re: [patch v2] mremap.2: Add description of old_size == 0 functionality Message-ID: <20170925123621.35godwzhvw4wbisc@dhcp22.suse.cz> References: <20170919214224.19561-1-mike.kravetz@oracle.com> <6fafdae8-4fea-c967-f5cd-d22c205608fa@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6fafdae8-4fea-c967-f5cd-d22c205608fa@gmail.com> User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 711 Lines: 17 On Wed 20-09-17 09:25:42, Michael Kerrisk wrote: [...] > BUGS > Before Linux 4.14, if old_size was zero and the mapping referred > to by old_address was a private mapping (mmap(2) MAP_PRIVATE), > mremap() created a new private mapping unrelated to the original > mapping. This behavior was unintended and probably unexpected in > user-space applications (since the intention of mremap() is to > create a new mapping based on the original mapping). Since Linux > 4.14, mremap() fails with the error EINVAL in this scenario. > > Does that seem okay? sorry to be late but yes this wording makes perfect sense to me. -- Michal Hocko SUSE Labs