From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751054AbdEHPrb (ORCPT ); Mon, 8 May 2017 11:47:31 -0400 Received: from bombadil.infradead.org ([65.50.211.133]:56369 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750776AbdEHPr3 (ORCPT ); Mon, 8 May 2017 11:47:29 -0400 Date: Mon, 8 May 2017 08:47:25 -0700 From: Darren Hart To: Mario.Limonciello@dell.com Cc: luto@kernel.org, pali.rohar@gmail.com, rjw@rjwysocki.net, len.brown@intel.com, corentin.chary@gmail.com, andriy.shevchenko@linux.intel.com, linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-pm@vger.kernel.org Subject: Re: RFC: WMI Enhancements Message-ID: <20170508154725.GD17700@fury> References: <201704191854.51783@pali> <4e3e507b116443298427002c5aafed7f@ausx13mpc120.AMER.DELL.COM> <20170420131431.GM18887@pali> <20170420204436.GC3209@fury> <775ffd8f3327497cabd15ee7826cedaf@ausx13mpc120.AMER.DELL.COM> <20170505234436.GB25865@fury> <20170508152907.GA17700@fury> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.8.0 (2017-02-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 08, 2017 at 03:36:31PM +0000, Mario.Limonciello@dell.com wrote: > > -----Original Message----- > > From: Darren Hart [mailto:dvhart@infradead.org] > > Sent: Monday, May 8, 2017 10:29 AM > > To: Andy Lutomirski > > Cc: Limonciello, Mario ; Pali Rohár > > ; Rafael J. Wysocki ; Len Brown > > ; Corentin Chary ; Andy > > Shevchenko ; linux-kernel@vger.kernel.org; > > platform-driver-x86@vger.kernel.org; linux-pm@vger.kernel.org > > Subject: Re: RFC: WMI Enhancements > > > > On Fri, May 05, 2017 at 06:25:08PM -0700, Andy Lutomirski wrote: > > > On Fri, May 5, 2017 at 5:51 PM, wrote: > > > >> -----Original Message----- > > > >> From: Darren Hart [mailto:dvhart@infradead.org] > > > >> Sent: Friday, May 5, 2017 6:45 PM > > > >> To: Limonciello, Mario > > > >> Cc: pali.rohar@gmail.com; rjw@rjwysocki.net; luto@amacapital.net; > > > >> len.brown@intel.com; corentin.chary@gmail.com; luto@kernel.org; > > > >> andriy.shevchenko@linux.intel.com; linux-kernel@vger.kernel.org; platform- > > > >> driver-x86@vger.kernel.org; linux-pm@vger.kernel.org > > > >> Subject: Re: RFC: WMI Enhancements > > > > > > > > > > I meant that to say that at least for now Andy's wmi-mof driver should still be > > merged. > > > > If something is going to build on top of this to do WBEM tools, they'll need that > > MOF > > > > data once someone figures out how to nicely deconstruct it. > > > > > > > > > > The thing I don't like about my own driver is that, as a WMI device > > > driver, it can be loaded before the rest of the bus finishes probing. > > > So user programs that are notified asynchronously that the wmi-mof > > > driver is loaded and try to use future functionality (ioctl to issue a > > > MOF-based method call?) might end up doing so before the rest of the > > > bus is probed. > > > > > > This could be addressed by always exposing the wmi-mof device last > > > (sort of -- it can be a module) or perhaps by moving MOF functionality > > > to the core driver. Or maybe it's not really a problem. > > > > Thanks Andy, I'll keep that in mind and see if I can come up with something to > > address it while working on WMI this week. > > > > The other problem with wmi-mof is that there will be no immediate open source > > consumers of the interface, and none on the horizon. We can't even test it to > > any meaningful degree on Linux. I suspect this will be met with stiff > > resistance. > > Well FWIW I did a quick PoC check with the binary that I got out of it to make > sure it matched what was supposed to be. I brought it over to a Win10 box and > decompiled using the mofcmp tool and those crazy arguments I mentioned and > it was correct. > > I'd argue that even if there is no open source tools available today, not making > the data available to userspace makes it difficult to even attempt to start > to reverse engineer. > > Kernel config with default of "N" perhaps for wmi-mof? All true. There is a precedent we're working against on this. I'll include it in my leveling-up thread today or tomorrow. > > > > > > > > Also, isn't there a way to ask Microsoft to document this? Are you > > > supposed to "ask a question" on this forum, perhaps: > > > > > > https://msdn.microsoft.com/en-us/library/gg134029.aspx > > > > > > I'm guessing the Samba team knows how to do this, too. > > > > > Microsoft treats this as an "intermediary" format. I'm not convinced > that anyone other than MS knows anything about it today. > > I agree asking them to document it is probably the right way to go. > Mario, you are most likely in a better position to do that than I am. Would you take that on? -- Darren Hart VMware Open Source Technology Center