Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750811AbWJLS3o (ORCPT ); Thu, 12 Oct 2006 14:29:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750967AbWJLS3o (ORCPT ); Thu, 12 Oct 2006 14:29:44 -0400 Received: from smtp.osdl.org ([65.172.181.4]:55260 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1750806AbWJLS3n (ORCPT ); Thu, 12 Oct 2006 14:29:43 -0400 Date: Thu, 12 Oct 2006 11:29:38 -0700 From: Andrew Morton To: Helge Hafting Cc: linux-kernel@vger.kernel.org Subject: Re: 2.6.19-rc1-mm1 - locks when using "dd bs=1M" from card reader Message-Id: <20061012112938.97ef924c.akpm@osdl.org> In-Reply-To: <452E327C.9020707@aitel.hist.no> References: <20061010000928.9d2d519a.akpm@osdl.org> <452E327C.9020707@aitel.hist.no> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.6; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 958 Lines: 26 On Thu, 12 Oct 2006 14:18:04 +0200 Helge Hafting wrote: > I found an easy way to hang the kernel when copying a SD-card: > > dd if=/dev/sdc of=file bs=1048576 > > I.e. copy the entire 256MB card in 1MB chunks. I got about > 160MB before the kernel hung. Not even sysrq+B worked, I needed > the reset button. The pc has a total of 512MB memory if that matters. > > Using bs=4096 instead let me copy the entire card with no problems, > but that seems to progress slower. > > The above 'dd' command hangs my office pc every time. So I can repeat > it for debugging purposes. > What device driver is providing /dev/sdc? Did any previous kernels work correctly? If so, which? - 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/