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    SubjectRE: RFC: WMI Enhancements
    Date
    > -----Original Message-----
    > From: Darren Hart [mailto:dvhart@infradead.org]
    > Sent: Monday, May 8, 2017 10:47 AM
    > To: Limonciello, Mario <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
    >
    > 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 <luto@kernel.org>
    > > > Cc: Limonciello, Mario <Mario_Limonciello@Dell.com>; Pali Rohár
    > > > <pali.rohar@gmail.com>; Rafael J. Wysocki <rjw@rjwysocki.net>; Len Brown
    > > > <len.brown@intel.com>; Corentin Chary <corentin.chary@gmail.com>; Andy
    > > > Shevchenko <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
    > > >
    > > > On Fri, May 05, 2017 at 06:25:08PM -0700, Andy Lutomirski wrote:
    > > > > On Fri, May 5, 2017 at 5:51 PM, <Mario.Limonciello@dell.com> wrote:
    > > > > >> -----Original Message-----
    > > > > >> From: Darren Hart [mailto:dvhart@infradead.org]
    > > > > >> Sent: Friday, May 5, 2017 6:45 PM
    > > > > >> To: Limonciello, Mario <Mario_Limonciello@Dell.com>
    > > > > >> 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?
    >

    Sure, I've made a request in that forum here:
    https://social.msdn.microsoft.com/Forums/en-US/cc3e50d6-c71d-4ce7-b765-6191f1788697/binary-mof-format?forum=os_specifications

    I'll keep you apprise if there is any further details provided by MS.

    Thanks,

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