From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268228AbUHTPQ1 (ORCPT ); Fri, 20 Aug 2004 11:16:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268174AbUHTPGs (ORCPT ); Fri, 20 Aug 2004 11:06:48 -0400 Received: from mx1.redhat.com ([66.187.233.31]:60367 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S267243AbUHTPEO (ORCPT ); Fri, 20 Aug 2004 11:04:14 -0400 Date: Fri, 20 Aug 2004 11:02:57 -0400 From: Alan Cox To: Oliver Neukum Cc: Pete Zaitcev , Nick Piggin , Hugh Dickins , arjanv@redhat.com, alan@redhat.com, greg@kroah.com, linux-kernel@vger.kernel.org, riel@redhat.com, sct@redhat.com Subject: Re: PF_MEMALLOC in 2.6 Message-ID: <20040820150257.GC6812@devserv.devel.redhat.com> References: <4125B111.2040308@yahoo.com.au> <20040820014005.73383a43@lembas.zaitcev.lan> <200408201650.07513.oliver@neukum.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200408201650.07513.oliver@neukum.org> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 20, 2004 at 04:50:07PM +0200, Oliver Neukum wrote: > > This is what made me suspect that it's the diry memory writeout problem. > > It's just like how it was on 2.4 before Alan added PF_MEMALLOC. > > If we add PF_MEMALLOC, do we solve the issue or make it only less > likely? Isn't there a need to limit users of the reserves in number? PF_MEMALLOC won't recurse. You might run out of memory however. The old world scsi drivers run in the thread of the I/O so are protected already by PF_MEMALLOC in those cases, its the thread nature of the USB driver which makes it more fun. Unless 2.6 vm is radically different I think PF_MEMALLOC is the right thing to set although it would always eventually be better to find out who is guilty of the blocking allocation that recurses. Are any of the VM guys considering PF_LOGALLOC so you can trace it down 8)