Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935188Ab0GSOn3 (ORCPT ); Mon, 19 Jul 2010 10:43:29 -0400 Received: from gir.skynet.ie ([193.1.99.77]:51602 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934486Ab0GSOn2 (ORCPT ); Mon, 19 Jul 2010 10:43:28 -0400 Date: Mon, 19 Jul 2010 15:43:11 +0100 From: Mel Gorman To: Christoph Hellwig Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Dave Chinner , Chris Mason , Nick Piggin , Rik van Riel , Johannes Weiner , Wu Fengguang , KAMEZAWA Hiroyuki , KOSAKI Motohiro , Andrew Morton , Andrea Arcangeli Subject: Re: [PATCH 6/8] fs,xfs: Allow kswapd to writeback pages Message-ID: <20100719144311.GS13117@csn.ul.ie> References: <1279545090-19169-1-git-send-email-mel@csn.ul.ie> <1279545090-19169-7-git-send-email-mel@csn.ul.ie> <20100719142051.GC12510@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20100719142051.GC12510@infradead.org> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1155 Lines: 28 On Mon, Jul 19, 2010 at 10:20:51AM -0400, Christoph Hellwig wrote: > On Mon, Jul 19, 2010 at 02:11:28PM +0100, Mel Gorman wrote: > > As only kswapd and memcg are writing back pages, there should be no > > danger of overflowing the stack. Allow the writing back of dirty pages > > in xfs from the VM. > > As pointed out during the discussion on one of your previous post memcg > does pose a huge risk of stack overflows. I remember. This is partially to nudge the memcg people to see where they currently stand with alleviating the problem. > In the XFS tree we've already > relaxed the check to allow writeback from kswapd, and until the memcg > situation we'll need to keep that check. > If memcg remains a problem, I'll drop these two patches. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/