[Intel-gfx] [PATCH v4 6/6] drm/i915: fix context/engine cleanup order

[Dave Gordon]

On 11/02/16 13:36, Chris Wilson wrote:
> On Sat, Jan 30, 2016 at 11:17:07AM +0000, Chris Wilson wrote:
>> On Fri, Jan 29, 2016 at 07:19:31PM +0000, Dave Gordon wrote:
>>> From: Nick Hoath <nicholas.hoath at intel.com>
>>>
>>> Swap the order of context & engine cleanup, so that contexts are cleaned
>>> up first, and *then* engines. This is a more sensible order anyway, but
>>> in particular has become necessary since the 'intel_ring_initialized()
>>> must be simple and inline' patch, which now uses ring->dev as an
>>> 'initialised' flag, so it can now be NULL after engine teardown. This in
>>> turn can cause a problem in the context code, which (used to) check the
>>> ring->dev->struct_mutex -- causing a fault if ring->dev was NULL.

[snip]

> It appears this patch was applied without dropping my r-b for the issue
> I pointed out above.
> -Chris

Not only that, but it was plucked from the end of the set of 6 patches 
without the earlier ones in the sequence, despite the cover letter [0/6] 
saying this:

     Patches reordered again; the bug fixes are now in patches 3 and 5.
     The former could stand alone; the latter depends on patch 4 and is
     a prerequisite for Nick's patch [6/6] to function.

So there's no chance that this one alone could be expected to work :(

.Dave.