[Nouveau] [PATCH 1/2] Revert "bus: remove cpu_coherent flag"

[Alexandre Courbot]

On Mon, Sep 19, 2016 at 12:43 PM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
> On Sun, Sep 18, 2016 at 11:39 PM, Alexandre Courbot <gnurou at gmail.com> wrote:
>> On Sun, Sep 18, 2016 at 7:21 PM, Karol Herbst <karolherbst at gmail.com> wrote:
>>> This reverts commit 01bbcb69f80e1058395b737ae399c6f4ef48691b.
>
> I think you meant aff51175cdbf345740ec9203eff88e772af88059 - that's
> the commit id that matters, not the one in Ben's non-linux repo.
>
>>>
>>> The commit caused fence timeouts within nvc0_screen_destroy and most likely
>>> other places as well.
>>>
>>> The most obvious effect is, that userspace processes take minutes to actually
>>> quit.
>>
>> Acked-by: Alexandre Courbot <acourbot at nvidia.com>
>
> If this doesn't make it into v4.8 (which is due to be released in a
> week), it should get tagged for stable as well.
>
> By the way, Alexandre, I believe Martin was reporting issues like this
> on his TK1 before this change as well. Probably worth investigating -
> sounds like there's a wider issue with TTM_PL_FLAG_UNCACHED and/or
> force_coherent.

Yes, it may be indeed related. I need to sync with Martin to
understand his exact repro case.