From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id 4550F6B0260 for ; Wed, 13 Jul 2016 03:50:27 -0400 (EDT) Received: by mail-wm0-f69.google.com with SMTP id o80so29083022wme.1 for ; Wed, 13 Jul 2016 00:50:27 -0700 (PDT) Received: from mail-wm0-f52.google.com (mail-wm0-f52.google.com. [74.125.82.52]) by mx.google.com with ESMTPS id c194si1832717wme.107.2016.07.13.00.50.25 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 13 Jul 2016 00:50:26 -0700 (PDT) Received: by mail-wm0-f52.google.com with SMTP id o80so55286487wme.1 for ; Wed, 13 Jul 2016 00:50:25 -0700 (PDT) Date: Wed, 13 Jul 2016 09:50:24 +0200 From: Michal Hocko Subject: Re: [PATCH] mm: gup: Re-define follow_page_mask output parameter page_mask usage Message-ID: <20160713075024.GB28723@dhcp22.suse.cz> References: <1468084625-26999-1-git-send-email-chengang@emindsoft.com.cn> <20160711141702.fb1879707aa2bcb290133a43@linux-foundation.org> <578522CE.9060905@emindsoft.com.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <578522CE.9060905@emindsoft.com.cn> Sender: owner-linux-mm@kvack.org List-ID: To: Chen Gang Cc: Andrew Morton , vbabka@suse.cz, kirill.shutemov@linux.intel.com, mingo@kernel.org, dave.hansen@linux.intel.com, dan.j.williams@intel.com, hannes@cmpxchg.org, jack@suse.cz, iamjoonsoo.kim@lge.com, jmarchan@redhat.com, dingel@linux.vnet.ibm.com, oleg@redhat.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Chen Gang On Wed 13-07-16 01:03:10, Chen Gang wrote: > On 7/12/16 05:17, Andrew Morton wrote: > > On Sun, 10 Jul 2016 01:17:05 +0800 chengang@emindsoft.com.cn wrote: > > > >> For a pure output parameter: > >> > >> - When callee fails, the caller should not assume the output parameter > >> is still valid. > >> > >> - And callee should not assume the pure output parameter must be > >> provided by caller -- caller has right to pass NULL when caller does > >> not care about it. > > > > Sorry, I don't think this one is worth merging really. > > > > OK, thanks, I can understand. > > It will be better if provide more details: e.g. > > - This patch is incorrect, or the comments is not correct. > > - The patch is worthless, at present. I would say the patch is not really needed. The code you are touching works just fine and there is no reason to touch it unless this is a part of a larger change where future changes would be easier to review/implement. -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org