Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030237AbXBQSPh (ORCPT ); Sat, 17 Feb 2007 13:15:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030238AbXBQSPg (ORCPT ); Sat, 17 Feb 2007 13:15:36 -0500 Received: from noname.neutralserver.com ([70.84.186.210]:27823 "EHLO noname.neutralserver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030237AbXBQSPf (ORCPT ); Sat, 17 Feb 2007 13:15:35 -0500 Message-ID: <45D7462D.6080700@monatomic.org> Date: Sat, 17 Feb 2007 20:15:09 +0200 From: Dan Aloni User-Agent: Icedove 1.5.0.9 (X11/20061220) MIME-Version: 1.0 To: Alan Stern CC: Linux Kernel List , linux-usb-devel-bounces@lists.sourceforge.net Subject: Re: [linux-usb-devel] OOM and USB, latest Linux 2.6 References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-PopBeforeSMTPSenders: da-x@monatomic.org X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - noname.neutralserver.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [0 0] / [47 12] X-AntiAbuse: Sender Address Domain - monatomic.org X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1483 Lines: 45 Alan Stern wrote: > On Sat, 17 Feb 2007, Dan Aloni wrote: > > >> Hello, >> >> Is it possible that OOM isn't handled very well if say, my entire >> file system structure is on a USB storage device? >> >> I'm not an expert on this particular matter but I'm pretty sure >> that I noticed GFP_KERNEL allocation being done on the write-out >> path in the usb-storage kernel thread, leading to a deadlock >> during OOM. >> > > Can you be any more specific than that? usb-storage should use only > GFP_NOIO in its I/O paths. > > > You are right, I looked over this state with kdb, and usb-storage waited in usb_stor_bulk_transfer_sg, which does pass GFP_NOIO at this scenario. It looked suspicious though, because OOM handling was invoked from many processes, and it didn't print about any process being killed and it didn't complain about no processes to kill either. (I'll look more into this, perhaps there's an OOM handling bug) BTW, soft-rebooting the machine in that state made the USB storage device (LEXAR, JD LIGHTNING II) inaccessible to the BIOS. I had to do a complete power cycle in order or the BIOS to see it again. -- Dan Aloni XIV LTD, http://www.xivstorage.com da-x (at) monatomic.org, dan (at) xiv.co.il - 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/