Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755250AbbGTUFv (ORCPT ); Mon, 20 Jul 2015 16:05:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59835 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752000AbbGTUFt (ORCPT ); Mon, 20 Jul 2015 16:05:49 -0400 Date: Mon, 20 Jul 2015 22:03:58 +0200 From: Oleg Nesterov To: Benjamin LaHaise Cc: Jeff Moyer , Andrew Morton , Joonsoo Kim , Fengguang Wu , Johannes Weiner , Stephen Rothwell , linux-next@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm-move-mremap-from-file_operations-to-vm_operations_struct-fix Message-ID: <20150720200358.GA22507@redhat.com> References: <20150716162444.26425f5e227387f1166a6d16@linux-foundation.org> <20150716235227.GA26551@redhat.com> <20150717140615.GA2779@kvack.org> <20150717223147.GA13259@redhat.com> <20150720173311.GA4379@redhat.com> <20150720175145.GH21558@kvack.org> <20150720183150.GA6868@redhat.com> <20150720192440.GA20573@redhat.com> <20150720193912.GJ21558@kvack.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150720193912.GJ21558@kvack.org> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1339 Lines: 38 On 07/20, Benjamin LaHaise wrote: > > On Mon, Jul 20, 2015 at 09:24:40PM +0200, Oleg Nesterov wrote: > > On 07/20, Oleg Nesterov wrote: > > > > > > But again, again, please ignore. This all is off-topic and my understanding > > > is very limited. > > > > Yes, yes, but sorry for noise and let me repeat... > > > > This memory lives in page-cache/lru, it is visible for shrinker which > > will unmap these pages for no reason on memory shortage. IOW, aio fools > > the kernel, this memory looks reclaimable but it is not. And we only do > > this for migration. > > And we have the same problem with O_DIRECT. I don't this so, or I misunderstood. Sure, dio_get_page() will pin the page. But not forever and this is unavoidable. This is not the same. OK, nevermind, lets forget this. > > And I should have changes the subject a long ago... So what do you think > > we should do with the build failure? > > I honestly don't care what of the options you do -- please just don't go > about adding BUG()s. OK, thanks. Then I'll send v2 which adds ifdef(MMU) into aio_ring_vm_ops tomorrow. Oleg. -- 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/