[PATCH 1/4] drm/radeon: add extra check in radeon_ttm_tt_unpin_userptr

[Christian König]

On 31.03.2015 18:13, Alex Deucher wrote:
> On Tue, Mar 31, 2015 at 11:36 AM, Christian König
> <deathsimple at vodafone.de> wrote:
>> From: Christian König <christian.koenig at amd.com>
>>
>> We somehow try to free the SG table twice.
>>
>> Bugs: https://bugs.freedesktop.org/show_bug.cgi?id=89734
>>
>> Signed-off-by: Christian König <christian.koenig at amd.com>
>> Cc: <stable at vger.kernel.org>
> For the series:
> Reviewed-by: Alex Deucher <alexander.deucher at amd.com>
>
> I've added the first two to my -fixes tree.

Could you add the other two to your -next tree? You probably need to 
merge with -fixes to do so.

Regards,
Christian.

>
> Alex
>
>> ---
>>   drivers/gpu/drm/radeon/radeon_ttm.c | 4 ++++
>>   1 file changed, 4 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c
>> index d02aa1d..b292aca 100644
>> --- a/drivers/gpu/drm/radeon/radeon_ttm.c
>> +++ b/drivers/gpu/drm/radeon/radeon_ttm.c
>> @@ -598,6 +598,10 @@ static void radeon_ttm_tt_unpin_userptr(struct ttm_tt *ttm)
>>          enum dma_data_direction direction = write ?
>>                  DMA_BIDIRECTIONAL : DMA_TO_DEVICE;
>>
>> +       /* double check that we don't free the table twice */
>> +       if (!ttm->sg->sgl)
>> +               return;
>> +
>>          /* free the sg table and pages again */
>>          dma_unmap_sg(rdev->dev, ttm->sg->sgl, ttm->sg->nents, direction);
>>
>> --
>> 1.9.1
>>