From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx121.postini.com [74.125.245.121]) by kanga.kvack.org (Postfix) with SMTP id 8F01A6B0002 for ; Wed, 20 Mar 2013 19:37:00 -0400 (EDT) Received: by mail-pb0-f49.google.com with SMTP id xa12so1755521pbc.36 for ; Wed, 20 Mar 2013 16:36:59 -0700 (PDT) Message-ID: <514A4815.4040206@gmail.com> Date: Thu, 21 Mar 2013 07:36:53 +0800 From: Simon Jeons MIME-Version: 1.0 Subject: Re: [PATCH 1/9] migrate: add migrate_entry_wait_huge() References: <1361475708-25991-1-git-send-email-n-horiguchi@ah.jp.nec.com> <1361475708-25991-2-git-send-email-n-horiguchi@ah.jp.nec.com> <5148FB6C.4070202@gmail.com> <1363816399-c6e7mofc-mutt-n-horiguchi@ah.jp.nec.com> In-Reply-To: <1363816399-c6e7mofc-mutt-n-horiguchi@ah.jp.nec.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Naoya Horiguchi Cc: linux-mm@kvack.org, Andrew Morton , Mel Gorman , Hugh Dickins , KOSAKI Motohiro , Andi Kleen , linux-kernel@vger.kernel.org Hi Naoya, On 03/21/2013 05:53 AM, Naoya Horiguchi wrote: > On Wed, Mar 20, 2013 at 07:57:32AM +0800, Simon Jeons wrote: >> Hi Naoya, >> On 02/22/2013 03:41 AM, Naoya Horiguchi wrote: >>> When we have a page fault for the address which is backed by a hugepage >>> under migration, the kernel can't wait correctly until the migration >>> finishes. This is because pte_offset_map_lock() can't get a correct >> It seems that current hugetlb_fault still wait hugetlb page under >> migration, how can it work without lock 2MB memory? > Hugetlb_fault() does call migration_entry_wait(), but returns immediately. Could you point out to me which code in function migration_entry_wait() lead to return immediately? > So page fault happens over and over again until the migration completes. > IOW, migration_entry_wait() is now broken for hugepage and doesn't work > as expected. > > Thanks, > Naoya -- 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