> -----Original Message----- > From: Darren Hart [mailto:[email protected]] > Sent: Friday, November 3, 2017 4:01 PM > To: Limonciello, Mario <[email protected]> > Cc: [email protected]; [email protected]; platform-driver- > [email protected]; [email protected]; [email protected]; > [email protected]; [email protected]; [email protected]; [email protected]; > [email protected]; [email protected] > Subject: Re: [PATCH v12 00/16] Introduce support for Dell SMBIOS over WMI > > On Fri, Nov 03, 2017 at 04:30:13PM +0000, [email protected] wrote: > > > -----Original Message----- > > > From: Darren Hart [mailto:[email protected]] > > > Sent: Thursday, November 2, 2017 7:50 PM > > > To: Limonciello, Mario <[email protected]> > > > Cc: Andy Shevchenko <[email protected]>; LKML <linux- > > > [email protected]>; [email protected]; Andy > Lutomirski > > > <[email protected]>; [email protected]; [email protected]; > > > [email protected]; [email protected]; [email protected]; Greg KH > <[email protected]>; > > > Alan Cox <[email protected]> > > > 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, > > > > The workflow currently goes first to review-dvhart, which 0-day will pull > from, > then to testing for integration, then to for-next. I plan to move it to > testing > today.
Gotcha, thanks.
