Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934489AbbGHHw3 (ORCPT ); Wed, 8 Jul 2015 03:52:29 -0400 Received: from cantor2.suse.de ([195.135.220.15]:59376 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933250AbbGHHwS (ORCPT ); Wed, 8 Jul 2015 03:52:18 -0400 Message-ID: <1436341873.5636.5.camel@suse.com> Subject: Re: [PATCH 1/1] suspend: delete sys_sync() From: Oliver Neukum To: "Rafael J. Wysocki" Cc: Dave Chinner , Henrique de Moraes Holschuh , Len Brown , Len Brown , One Thousand Gnomes , Alan Stern , "linux-kernel@vger.kernel.org" , Linux PM list Date: Wed, 08 Jul 2015 09:51:13 +0200 In-Reply-To: <1522789.fQO6RUUx40@vostro.rjw.lan> References: <4290667.ZqInAykFGS@vostro.rjw.lan> <1527037.PaGp0dsCau@vostro.rjw.lan> <1436279906.2658.4.camel@suse.de> <1522789.fQO6RUUx40@vostro.rjw.lan> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.11 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1184 Lines: 29 On Wed, 2015-07-08 at 00:11 +0200, Rafael J. Wysocki wrote: > On Tuesday, July 07, 2015 04:38:26 PM Oliver Neukum wrote: > > > That is a tough nut. But that's not a reason to make it worse. > > I'd say there's no reason not to use a secondary interface to > > suspend without syncing or to extend or introduce such an interface > > if the API is deficient. > > Well, the point here is that the sync we have doesn't prevent all potentially > possible bad things from happening. It's a partial measure at best in that > respect. Well, removed hardware doesn't work. That is a very basic limitation. But can we guarantee that any returned syscall actually wrote to disk? Yes, but it must be done in kernel space. So doing a sync has a true benefit. I don't see why you would want to generally remove it. What is wrong with an interface allowing a selection there to those who don't care about additional guarantees? Regards Oliver -- 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/