Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763308AbXHCOlW (ORCPT ); Fri, 3 Aug 2007 10:41:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762325AbXHCOlP (ORCPT ); Fri, 3 Aug 2007 10:41:15 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:45551 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751029AbXHCOlO (ORCPT ); Fri, 3 Aug 2007 10:41:14 -0400 Date: Fri, 3 Aug 2007 10:41:13 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Matthew Garrett cc: David Brownell , Rogan Dawes , Oliver Neukum , Greg KH , , Subject: Re: [PATCH] USB: Only enable autosuspend by default on certain device classes In-Reply-To: <20070803143338.GA19713@srcf.ucam.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1187 Lines: 30 On Fri, 3 Aug 2007, Matthew Garrett wrote: > Windows will autosuspend hubs, bluetooth devices, HID devices and CDC > devices, so I think we're safe suspending those by default. And we know that we're not safe suspending scanners and many printers by default. But that leaves plenty of other device classes unaccounted for. > I'm not so > enthusiastic about the "Increase the timeout case" - it doesn't avoid > any races, just makes them less likely. USB is likely to get loaded in > the initramfs, but we may not have a full set of udev rules until the > root fs is up and that can take an effectively arbitrarily large amount > of time. If it takes longer than 15 minutes, something is wrong. At that point the user will have worse things to worry about than whether some USB devices got suspended. And 15 minutes is a perfectly reasonable autosuspend timeout for devices that might be plugged in all day long. Alan Stern - 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/