From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f182.google.com (mail-pd0-f182.google.com [209.85.192.182]) by kanga.kvack.org (Postfix) with ESMTP id 8D7186B007B for ; Tue, 10 Dec 2013 03:35:36 -0500 (EST) Received: by mail-pd0-f182.google.com with SMTP id v10so6843261pde.41 for ; Tue, 10 Dec 2013 00:35:36 -0800 (PST) Received: from LGEMRELSE7Q.lge.com (LGEMRELSE7Q.lge.com. [156.147.1.151]) by mx.google.com with ESMTP id ek3si9812532pbd.25.2013.12.10.00.35.32 for ; Tue, 10 Dec 2013 00:35:34 -0800 (PST) Date: Tue, 10 Dec 2013 17:38:25 +0900 From: Joonsoo Kim Subject: Re: [PATCH v2 2/7] mm/migrate: correct failure handling if !hugepage_migration_support() Message-ID: <20131210083825.GB24992@lge.com> References: <1386580248-22431-1-git-send-email-iamjoonsoo.kim@lge.com> <1386580248-22431-3-git-send-email-iamjoonsoo.kim@lge.com> <00000142d8263858-5c29199b-77e5-47a5-9db6-2ea6ea7c7fc8-000000@email.amazonses.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <00000142d8263858-5c29199b-77e5-47a5-9db6-2ea6ea7c7fc8-000000@email.amazonses.com> Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Lameter Cc: Andrew Morton , Mel Gorman , Rik van Riel , Rafael Aquini , Naoya Horiguchi , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Vlastimil Babka , Zhang Yanfei On Mon, Dec 09, 2013 at 04:17:32PM +0000, Christoph Lameter wrote: > On Mon, 9 Dec 2013, Joonsoo Kim wrote: > > > We should remove the page from the list if we fail without ENOSYS, > > since migrate_pages() consider error cases except -ENOMEM and -EAGAIN > > as permanent failure and it assumes that the page would be removed from > > the list. Without this patch, we could overcount number of failure. > > Ok what does the patch do about this? I dont see any modifications. Remove > this part of the description? Description is slightly wrong. Following is correct one. "We should remove the page from the list if we fail *with* ENOSYS," And this patch do this by adding putback_active_hugepage(hpage) on ENOSYS case. > > > In addition, we should put back the new hugepage if > > !hugepage_migration_support(). If not, we would leak hugepage memory. > > Ok looks like that is fixed by this patch. > > Acked-by: Christoph Lameter Thanks. -- 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