From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id 730466B0078 for ; Thu, 21 Jan 2010 15:41:34 -0500 (EST) Date: Thu, 21 Jan 2010 14:40:41 -0600 (CST) From: Christoph Lameter Subject: Re: [PATCH 22 of 30] pmd_trans_huge migrate bugcheck In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Andrea Arcangeli Cc: linux-mm@kvack.org, Marcelo Tosatti , Adam Litke , Avi Kivity , Izik Eidus , Hugh Dickins , Nick Piggin , Rik van Riel , Mel Gorman , Andi Kleen , Dave Hansen , Benjamin Herrenschmidt , Ingo Molnar , Mike Travis , KAMEZAWA Hiroyuki , Chris Wright Dave Hansen , Andrew Morton List-ID: On Thu, 21 Jan 2010, Andrea Arcangeli wrote: > From: Andrea Arcangeli > > No pmd_trans_huge should ever materialize in migration ptes areas, because > try_to_unmap will split the hugepage before migration ptes are instantiated. try_to_unmap? How do you isolate the hugepages from the LRU? If you do isolate the huge pages via a LRU and get a 2M page then the migration logic has to be modified to be aware that huge pages may split during try_to_unmap. -- 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