[Intel-gfx] [3.0-rc3] i915: potentially stale ring data during resume

[Ben Widawsky]

On Sat, Jun 18, 2011 at 02:48:29PM +0800, Daniel J Blueman wrote:
> Hi Eric, Chris,
> 
> There are quite a lot of callers of I915_READ/WRITE which aren't
> holding the dev->struct_mutex lock across device suspend and resume
> operations, to prevent the GT going to sleep early if two callers are
> in the gen6_gt_force_wake_get->gen6_gt_force_wake_put critical region.
> 
> I started cooking up a patch, but ran out of time.

Please note the only register range that matters is 0-0x40000
(don't ask how we know that).

Ben