From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761929AbYEOQd0 (ORCPT ); Thu, 15 May 2008 12:33:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758257AbYEOQdR (ORCPT ); Thu, 15 May 2008 12:33:17 -0400 Received: from mx1.redhat.com ([66.187.233.31]:56242 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757406AbYEOQdQ (ORCPT ); Thu, 15 May 2008 12:33:16 -0400 Date: Thu, 15 May 2008 12:33:15 -0400 From: Bill Nottingham To: linux-kernel@vger.kernel.org Subject: Problems with suspend and USB storage Message-ID: <20080515163315.GA17779@nostromo.devel.redhat.com> Mail-Followup-To: linux-kernel@vger.kernel.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I've been testing suspend/hibernate with various USB devices under 2.6.25.2. Test box is a Thinkpad T60 (uhci, ehci). The results are somewhat dismal. Using USB as a hibernate device: - A directly connected USB stick works OK as a hibernate device - A directly connected USB hard drive works OK as a hibernate device - A USB stick connected via an ExpressCard reader does not - it appears to just not be there when the hibernate code attemps to write the data. On resume (from either hibernate or suspend from RAM): - Any 'in use' USB storage, whether it be as swap (a hibernate device), or a mounted filesystem, immediately generates errors on resume. It appears the filesystem and/or swap tasks are woken up before the actual USB device - it enumerates the disks after the errors have already been thrown. - As a consequence, the USB devices shift their device names - Using USB_PERSIST has no effect on this problem - This appears to happen for all USB connection types (hard drive, stick, via ExpressCard reader.) Is there any way to get sane behavior out of suspend/resume with USB storage? Bill