lkml.org 
[lkml]   [2017]   [Nov]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH v12 00/16] Introduce support for Dell SMBIOS over WMI
Date
> -----Original Message-----
> From: Darren Hart [mailto:dvhart@infradead.org]
> Sent: Thursday, November 2, 2017 7:50 PM
> To: Limonciello, Mario <Mario_Limonciello@Dell.com>
> Cc: Andy Shevchenko <andy.shevchenko@gmail.com>; LKML <linux-
> kernel@vger.kernel.org>; platform-driver-x86@vger.kernel.org; Andy Lutomirski
> <luto@kernel.org>; quasisec@google.com; pali.rohar@gmail.com;
> rjw@rjwysocki.net; mjg59@google.com; hch@lst.de; Greg KH <greg@kroah.com>;
> Alan Cox <gnomes@lxorguk.ukuu.org.uk>
> Subject: Re: [PATCH v12 00/16] Introduce support for Dell SMBIOS over WMI
>
> On Wed, Nov 01, 2017 at 02:25:21PM -0500, Mario Limonciello wrote:
> > The existing way that the dell-smbios helper module and associated
> > other drivers (dell-laptop, dell-wmi) communicate with the platform
> > really isn't secure. It requires creating a buffer in physical
> > DMA32 memory space and passing that to the platform via SMM.
> >
> > Since the platform got a physical memory pointer, you've just got
> > to trust that the platform has only modified (and accessed) memory
> > within that buffer.
> >
> > Dell Platform designers recognize this security risk and offer a
> > safer way to communicate with the platform over ACPI. This is
> > in turn exposed via a WMI interface to the OS.
> >
> > When communicating over WMI-ACPI the communication doesn't occur
> > with physical memory pointers. When the ASL is invoked, the fixed
> > length ACPI buffer is copied to a small operating region. The ASL
> > will invoke the SMI, and SMM will only have access to this operating
> > region. When the ASL returns the buffer is copied back for the OS
> > to process.
> >
> > This method of communication should also deprecate the usage of the
> > dcdbas kernel module and software dependent upon it's interface.
> > Instead offer a character device interface for communicating with this
> > ASL method to allow userspace to use instead.
> >
> > To faciliate that this patch series introduces a generic way for WMI
> > drivers to be able to create discoverable character devices with
> > a predictable IOCTL interface through the WMI bus when desired.
> > Requiring WMI drivers to explicitly ask for this functionality will
> > act as an effective vendor whitelist to character device creation.
> >
> > Some of this work is the basis for what will be a proper interpreter
> > of MOF in the kernel and controls for what drivers will be able to
> > do with that MOF.
> >
> > NOTE: This patch series is intended to go on top of platform-drivers-x86
> > linux-next.
> >
> > For convenience the entire series including those is also available here:
> > https://github.com/dell/linux/tree/wmi-smbios
>
> Queued for testing, thanks Mario.
>
> --
> Darren Hart
> VMware Open Source Technology Center

Thanks Darren. BTW Did you forget to push? I didn't see it at the testing branch:
http://git.infradead.org/users/dvhart/linux-platform-drivers-x86.git/shortlog/refs/heads/testing

Thanks,

\
 
 \ /
  Last update: 2017-11-03 17:30    [W:1.476 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site