[PATCH v7 12/16] drm/amdgpu: Fix hang on device removal.

[Christian König]

Ok, then putting that on my TODO list for tomorrow.

I've already found a problem with how we finish of fences, going to 
write more on this tomorrow.

Christian.

Am 17.05.21 um 21:46 schrieb Andrey Grodzovsky:
> Yep, you can take a look.
>
> Andrey
>
> On 2021-05-17 3:39 p.m., Christian König wrote:
>> You need to note who you are pinging here.
>>
>> I'm still assuming you wait for feedback from Daniel. Or should I 
>> take a look?
>>
>> Christian.
>>
>> Am 17.05.21 um 16:40 schrieb Andrey Grodzovsky:
>>> Ping
>>>
>>> Andrey
>>>
>>> On 2021-05-14 10:42 a.m., Andrey Grodzovsky wrote:
>>>> Ping
>>>>
>>>> Andrey
>>>>
>>>> On 2021-05-12 10:26 a.m., Andrey Grodzovsky wrote:
>>>>> If removing while commands in flight you cannot wait to flush the
>>>>> HW fences on a ring since the device is gone.
>>>>>
>>>>> Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky at amd.com>
>>>>> ---
>>>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c | 16 ++++++++++------
>>>>>   1 file changed, 10 insertions(+), 6 deletions(-)
>>>>>
>>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c 
>>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
>>>>> index 1ffb36bd0b19..fa03702ecbfb 100644
>>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
>>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
>>>>> @@ -36,6 +36,7 @@
>>>>>   #include <linux/firmware.h>
>>>>>   #include <linux/pm_runtime.h>
>>>>> +#include <drm/drm_drv.h>
>>>>>   #include "amdgpu.h"
>>>>>   #include "amdgpu_trace.h"
>>>>> @@ -525,8 +526,7 @@ int amdgpu_fence_driver_init(struct 
>>>>> amdgpu_device *adev)
>>>>>    */
>>>>>   void amdgpu_fence_driver_fini_hw(struct amdgpu_device *adev)
>>>>>   {
>>>>> -    unsigned i, j;
>>>>> -    int r;
>>>>> +    int i, r;
>>>>>       for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
>>>>>           struct amdgpu_ring *ring = adev->rings[i];
>>>>> @@ -535,11 +535,15 @@ void amdgpu_fence_driver_fini_hw(struct 
>>>>> amdgpu_device *adev)
>>>>>               continue;
>>>>>           if (!ring->no_scheduler)
>>>>>               drm_sched_fini(&ring->sched);
>>>>> -        r = amdgpu_fence_wait_empty(ring);
>>>>> -        if (r) {
>>>>> -            /* no need to trigger GPU reset as we are unloading */
>>>>> +        /* You can't wait for HW to signal if it's gone */
>>>>> +        if (!drm_dev_is_unplugged(&adev->ddev))
>>>>> +            r = amdgpu_fence_wait_empty(ring);
>>>>> +        else
>>>>> +            r = -ENODEV;
>>>>> +        /* no need to trigger GPU reset as we are unloading */
>>>>> +        if (r)
>>>>>               amdgpu_fence_driver_force_completion(ring);
>>>>> -        }
>>>>> +
>>>>>           if (ring->fence_drv.irq_src)
>>>>>               amdgpu_irq_put(adev, ring->fence_drv.irq_src,
>>>>>                          ring->fence_drv.irq_type);
>>>>>
>>