[PATCH] drm/amdgpu: release parent fence reference

[Christian König]

Am 24.10.2016 um 11:43 schrieb Grazvydas Ignotas:
> On Mon, Oct 24, 2016 at 12:13 PM, Christian König
> <deathsimple at vodafone.de> wrote:
>> Am 24.10.2016 um 04:25 schrieb zhoucm1:
>>>
>>>
>>> On 2016年10月24日 02:31, Grazvydas Ignotas wrote:
>>>> It's done in amd_sched_hw_job_reset(), but not in normal job processing.
>>>> Leak reported by CONFIG_SLUB_DEBUG.
>>>>
>>>> Signed-off-by: Grazvydas Ignotas <notasas at gmail.com>
>>>> ---
>>>>    CONFIG_SLUB_DEBUG reports more leaks related to ioctls,
>>>>    but I was unable to track them down...
>>>>
>>>>    drivers/gpu/drm/amd/scheduler/gpu_scheduler.c | 2 ++
>>>>    1 file changed, 2 insertions(+)
>>>>
>>>> diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
>>>> b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
>>>> index 910b8d5..cfb686e 100644
>>>> --- a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
>>>> +++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
>>>> @@ -522,6 +522,8 @@ static void amd_sched_process_job(struct fence *f,
>>>> struct fence_cb *cb)
>>>>          trace_amd_sched_process_job(s_fence);
>>>>        fence_put(&s_fence->finished);
>>>> +    fence_put(s_fence->parent);
>>> If I remember correctly, parent was put in sched fence release.
>>
>> Yes, exactly. It's only released in amd_sched_hw_job_reset() because we want
>> to assign a new parent fence.
> Well then it doesn't work, SLUB_DEBUG detects leaks on teardown, and
> with my patch they're gone.
> Perhaps the problem is that when new parent fence is assigned, the old
> one is not put? I won't be able to check until the weekend, so if
> anybody else can do it, please go ahead.

Mhm, what steps do you do to reproduce this?

I'm looking into this a bit and it sounds like we just doesn't correctly 
tear down the scheduler on driver unload.

Regards,
Christian.

>
> Gražvydas