From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757439Ab3BRWNN (ORCPT ); Mon, 18 Feb 2013 17:13:13 -0500 Received: from mail.skyhub.de ([78.46.96.112]:43528 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757027Ab3BRWNK (ORCPT ); Mon, 18 Feb 2013 17:13:10 -0500 Date: Mon, 18 Feb 2013 23:13:06 +0100 From: Borislav Petkov To: Greg KH Cc: Mauro Carvalho Chehab , balbi@ti.com, Linux Kernel Mailing List , Steven Rostedt , Frederic Weisbecker , Ingo Molnar , JBottomley@parallels.com, linux-scsi@vger.kernel.org, davem@davemloft.net, netdev@vger.kernel.org, Doug Thompson , linux-edac@vger.kernel.org, rjw@sisk.pl, linux-pm@vger.kernel.org Subject: Re: SYSFS "errors" Message-ID: <20130218221306.GA21493@pd.tnic> Mail-Followup-To: Borislav Petkov , Greg KH , Mauro Carvalho Chehab , balbi@ti.com, Linux Kernel Mailing List , Steven Rostedt , Frederic Weisbecker , Ingo Molnar , JBottomley@parallels.com, linux-scsi@vger.kernel.org, davem@davemloft.net, netdev@vger.kernel.org, Doug Thompson , linux-edac@vger.kernel.org, rjw@sisk.pl, linux-pm@vger.kernel.org References: <20130218155012.GA30974@kroah.com> <20130218155215.GB2663@arwen.pp.htv.fi> <20130218171334.GA31329@kroah.com> <20130218172700.GH2663@arwen.pp.htv.fi> <20130218174916.GA2070@kroah.com> <20130218184633.GC10755@arwen.pp.htv.fi> <20130218164638.7cb53baa@redhat.com> <20130218200542.GB20137@arwen.pp.htv.fi> <20130218184742.5a4c3c06@redhat.com> <20130218215434.GB16794@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20130218215434.GB16794@kroah.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 18, 2013 at 01:54:34PM -0800, Greg KH wrote: > Because sysfs is "one value per file" the lack of a file showing up > shouldn't cause any userspace tools any problems, that is why we did > things this way. > > But, of course, userspace programmers do know how to mess things up... How about what I proposed earlier to Felipe: -- diff --git a/drivers/edac/edac_mc_sysfs.c b/drivers/edac/edac_mc_sysfs.c index 0ca1ca71157f..d2eef76d1d46 100644 --- a/drivers/edac/edac_mc_sysfs.c +++ b/drivers/edac/edac_mc_sysfs.c @@ -704,7 +704,7 @@ static ssize_t mci_sdram_scrub_rate_show(struct device *dev, int bandwidth = 0; if (!mci->get_sdram_scrub_rate) - return -ENODEV; + return sprintf(data, "N/A"); bandwidth = mci->get_sdram_scrub_rate(mci); if (bandwidth < 0) { -- Would that hurt the sysfs policy? In this case we *can* read the file and it correctly tells us that scrub rate reading is not supported instead of having a number there. Hmm. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --