From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752843AbdJGMjO (ORCPT ); Sat, 7 Oct 2017 08:39:14 -0400 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:60201 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751027AbdJGMjM (ORCPT ); Sat, 7 Oct 2017 08:39:12 -0400 X-ME-Sender: X-Sasl-enc: ZyPC7tdj+jj45DPwgdRp4yZzCTbiFEWIsx3rtekBbzO/ 1507379951 Date: Sat, 7 Oct 2017 14:39:21 +0200 From: Greg KH To: Mario.Limonciello@dell.com Cc: dvhart@infradead.org, andy.shevchenko@gmail.com, linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org, luto@kernel.org, quasisec@google.com, pali.rohar@gmail.com, rjw@rjwysocki.net, mjg59@google.com, hch@lst.de Subject: Re: [PATCH v5 08/14] platform/x86: dell-smbios: Add a sysfs interface for SMBIOS tokens Message-ID: <20171007123921.GC5667@kroah.com> References: <20171007065421.GA20756@kroah.com> <8ad76b287f8a4f9aa13e7c809cc7b998@ausx13mpc120.AMER.DELL.COM> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8ad76b287f8a4f9aa13e7c809cc7b998@ausx13mpc120.AMER.DELL.COM> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Oct 07, 2017 at 11:56:04AM +0000, Mario.Limonciello@dell.com wrote: > > -----Original Message----- > > From: Greg KH [mailto:greg@kroah.com] > > Sent: Saturday, October 7, 2017 1:54 AM > > To: Limonciello, Mario > > Cc: dvhart@infradead.org; Andy Shevchenko ; > > LKML ; platform-driver-x86@vger.kernel.org; > > Andy Lutomirski ; quasisec@google.com; > > pali.rohar@gmail.com; rjw@rjwysocki.net; mjg59@google.com; hch@lst.de > > Subject: Re: [PATCH v5 08/14] platform/x86: dell-smbios: Add a sysfs interface for > > SMBIOS tokens > > > > On Fri, Oct 06, 2017 at 11:59:52PM -0500, Mario Limonciello wrote: > > > Currently userspace tools can access system tokens via the dcdbas > > > kernel module and a SMI call that will cause the platform to execute > > > SMM code. > > > > > > With a goal in mind of deprecating the dcdbas kernel module a different > > > method for accessing these tokens from userspace needs to be created. > > > > > > This is intentionally marked to only be readable as root as it can > > > contain sensitive information about the platform's configuration. > > > > > > MAINTAINERS was missing for this driver. Add myself and Pali to > > > maintainers list for it. > > > > > > Signed-off-by: Mario Limonciello > > > --- > > > .../ABI/testing/sysfs-platform-dell-smbios | 16 ++++++ > > > MAINTAINERS | 7 +++ > > > drivers/platform/x86/dell-smbios.c | 64 ++++++++++++++++++++++ > > > 3 files changed, 87 insertions(+) > > > create mode 100644 Documentation/ABI/testing/sysfs-platform-dell-smbios > > > > > > diff --git a/Documentation/ABI/testing/sysfs-platform-dell-smbios > > b/Documentation/ABI/testing/sysfs-platform-dell-smbios > > > new file mode 100644 > > > index 000000000000..d97f4bd5bd91 > > > --- /dev/null > > > +++ b/Documentation/ABI/testing/sysfs-platform-dell-smbios > > > @@ -0,0 +1,16 @@ > > > +What: /sys/devices/platform//tokens > > > +Date: November 2017 > > > +KernelVersion: 4.15 > > > +Contact: "Mario Limonciello" > > > +Description: > > > + A read-only description of Dell platform tokens > > > + available on the machine. > > > + > > > + The tokens will be displayed in the following > > > + machine readable format with each token on a > > > + new line: > > > + > > > + ID Location value > > > + > > > + For example token: > > > + 5 5 3 > > > > That's more than "one value per file" which is what sysfs requires, so > > this isn't acceptable, sorry. > > What's more acceptable to you to relay this information? > Binary sysfs attribute and export the structure format in a uapi? binary sysfs apis are for passing "raw" data to/from firmware/hardware to userspace, without the kernel knowing anything about the structure or format of the data. Putting the format in a structure in a uapi header kind of defeats that purpose :) > or a collection of sysfs files? > Eg: > tokens/$x/id > tokens/$x/location > tokens/$s/value > > I'm guessing the latter is the better way to go. Good guess :) thanks, greg k-h