[Intel-gfx] [CI, v3, 1/2] drm/i915: Prevent a race during I915_GEM_MMAP ioctl with WC set

[Guenter Roeck]

On Thu, Feb 28, 2019 at 10:34:20PM +0000, Chris Wilson wrote:
> Quoting Guenter Roeck (2019-02-28 22:27:35)
> > On Thu, Feb 28, 2019 at 10:18:32PM +0000, Chris Wilson wrote:
> > > 
> > > If you have userspace that is broken, we need to fix it. We can get away
> > > with quietly changing ABI only so long as nobody notices. It sounds like
> > > you have some userspace that will break if you updated the kernel; ergo
> > > we have a problem.
> > > 
> > > We just need that as a clear statement so that we have the user impact
> > > recorded.
> > 
> > Yes, it does break our userspace code. I fixed the problem in our kernels
> > with the following patch:
> > 
> And what userspace is that? Details for the log, please.

Internal agreement is that we'll fix our userspace code.

Guenter