Re: [PATCH v3 4/8] platform/x86: wmi: create character devices when requested by drivers

From: Greg KH
Date: Sun Oct 01 2017 - 14:07:37 EST


On Sun, Oct 01, 2017 at 02:25:00PM +0000, Mario.Limonciello@xxxxxxxx wrote:
> > -----Original Message-----
> > From: Greg KH [mailto:gregkh@xxxxxxxxxxxxxxxxxxx]
> > Sent: Sunday, October 1, 2017 8:24 AM
> > To: Limonciello, Mario <Mario_Limonciello@xxxxxxxx>
> > Cc: dvhart@xxxxxxxxxxxxx; andy.shevchenko@xxxxxxxxx; linux-
> > kernel@xxxxxxxxxxxxxxx; platform-driver-x86@xxxxxxxxxxxxxxx; luto@xxxxxxxxxx;
> > quasisec@xxxxxxxxxx; pali.rohar@xxxxxxxxx; rjw@xxxxxxxxxxxxx;
> > mjg59@xxxxxxxxxx; hch@xxxxxx
> > Subject: Re: [PATCH v3 4/8] platform/x86: wmi: create character devices when
> > requested by drivers
> >
> > On Sat, Sep 30, 2017 at 07:26:57PM +0000, Mario.Limonciello@xxxxxxxx wrote:
> > > I think what's Darren's most interested in is the that conceptually this is
> > > an approach you can agree with.
> > >
> > > "A WMI vendor driver binds to the WMI bus and requests the WMI bus to
> > create
> > > a character device. The WMI bus creates a character device /dev/wmi/$driver
> > > which the WMI vendor driver will process all various file operations."
> >
> > We've been over this before, let's see that actual implementation which
> > defines the "will process all..." implementation to see if that is
> > actually an acceptable thing.
> >
> > thanks,
> >
> > greg k-h
>
> I'm working on changes still (that you'll be CC on), but I don't expect this specific
> concept to change in the future changes:
>
> Bus creating character device:
> https://patchwork.kernel.org/patch/9975283/

A bit hard to comment on web pages, and I would like to point out your
obvious memory leak, but it's hard to do that this way :(

> Driver requesting character device:
> https://patchwork.kernel.org/patch/9975263/

There's other issues with this patch as well, I'll wait for a real one
in my inbox to be able to actually review it :(

thanks,

greg k-h