Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935825AbYCFUyw (ORCPT ); Thu, 6 Mar 2008 15:54:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S935600AbYCFUxr (ORCPT ); Thu, 6 Mar 2008 15:53:47 -0500 Received: from rv-out-0910.google.com ([209.85.198.189]:18769 "EHLO rv-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935602AbYCFUxp (ORCPT ); Thu, 6 Mar 2008 15:53:45 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=rlE8wZgSQAbIc8cyZT4bbavIC6iDbsVz9c97nOcDLXniBPOFxMqkKLGSm5bWYmTIJv27KxNTizjw92DbZP6/itJ94DMajWg0nMh5cvmd9si1C032GcdhNs0rUkj4vsUo2/eXCoqqfYE6LPzCMj7Ku9ddgQloIlaO8NPihVTWeXI= Message-ID: Date: Thu, 6 Mar 2008 21:53:44 +0100 From: "Zdenek Kabelac" To: "Alan Stern" Subject: Re: Bugs in MMC [was: [Bug 10030] Suspend doesn't work when SD card is inserted] Cc: "Pavel Machek" , "David Brownell" , "Pierre Ossman" , "Rafael J. Wysocki" , "pm list" , "Kernel development list" In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080306155553.GA3908@ucw.cz> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2024 Lines: 46 2008/3/6, Alan Stern : > On Thu, 6 Mar 2008, Pavel Machek wrote: > > > On Tue 2008-03-04 16:00:51, Alan Stern wrote: > > > On Tue, 4 Mar 2008, David Brownell wrote: > > > > > > > > What's wrong with a superfluous probe at resume time, besides the waste > > > > > of a few milliseconds? > > > > > > > > I'm more concerned with the undesirable removal of devices at suspend > > > > time ... ones with mounted filesystems etc. > > > > > > On that we can agree. The removal is done if the host doesn't define a > > > resume method. There doesn't seem to be any point to that, given that > > > the probing during resume will determine whether a card has in fact > > > been removed. > > > > Hmm, if the driver is sleeping too deeply, user might have removed the > > card and put in different one, without driver noticing. That would be > > _bad_. > > > Ironically, the very same problem now exists with the USB mass-storage > driver. I don't see any way for the driver itself to solve it, > especially during a hibernation (which can be a _very_ deep sleep). > > One thing that could be done is for filesystems to verify, after a > system sleep, that their superblocks haven't changed. There could > still be issues with non-mounted partitions, if they have live entries > in the block cache, but it would be an improvement. > > Do you know the right people to mention this to? Anybody in filesystem > development interested in suspend/hibernation issues? IMHO the way would be to try to unmount fs if it's possible - if not - user should be notified on suspend/hibernation that he must preserve media in its place after resume and it should be checked and user should be notified if different devices/fs were find... Zdenek -- 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/