From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx150.postini.com [74.125.245.150]) by kanga.kvack.org (Postfix) with SMTP id D41E76B005A for ; Tue, 17 Jul 2012 11:45:43 -0400 (EDT) Received: by obhx4 with SMTP id x4so1001679obh.14 for ; Tue, 17 Jul 2012 08:45:43 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <1342528415-2291-1-git-send-email-js1304@gmail.com> <1342528415-2291-3-git-send-email-js1304@gmail.com> Date: Wed, 18 Jul 2012 00:45:42 +0900 Message-ID: Subject: Re: [PATCH 3/4 v2] mm: fix return value in __alloc_contig_migrate_range() From: JoonSoo Kim Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org List-ID: To: Michal Nazarewicz Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Marek Szyprowski , Minchan Kim , Christoph Lameter 2012/7/17 Michal Nazarewicz : > On Tue, 17 Jul 2012 14:33:34 +0200, Joonsoo Kim wrote: >> >> migrate_pages() would return positive value in some failure case, >> so 'ret > 0 ? 0 : ret' may be wrong. >> This fix it and remove one dead statement. > > > How about the following message: > > ------------------- >8 --------------------------------------------------- > migrate_pages() can return positive value while at the same time emptying > the list of pages it was called with. Such situation means that it went > through all the pages on the list some of which failed to be migrated. > > If that happens, __alloc_contig_migrate_range()'s loop may finish without > "++tries == 5" never being checked. This in turn means that at the end > of the function, ret may have a positive value, which should be treated > as an error. > > This patch changes __alloc_contig_migrate_range() so that the return > statement converts positive ret value into -EBUSY error. > ------------------- >8 --------------------------------------------------- It's good. I will resend patch replacing my comment with yours. Thanks for help. -- 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