[PATCH] drm/amdgpu:fix race condition bug

[Christian König]

Am 07.04.2017 um 13:26 schrieb Christian König:
> Am 07.04.2017 um 12:52 schrieb Monk Liu:
>> Change-Id: Ib7a03f3cf5594deeb4ad333cc59b47a6bddfd1ad
>> Signed-off-by: Monk Liu <Monk.Liu at amd.com>
>
> NAK, that is a not backward compatible change to the IOCTL interface.

To make it clear, something like "if(seq == ~0L)" should work.

Christian.

>
> And BTW what's the background of it?
>
> Christian.
>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c | 3 +++
>>   1 file changed, 3 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
>> index 6d86eae..b8c11fe 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
>> @@ -277,6 +277,9 @@ struct fence *amdgpu_ctx_get_fence(struct 
>> amdgpu_ctx *ctx,
>>         spin_lock(&ctx->ring_lock);
>>   +    if (!seq)
>> +        seq = ctx->rings[ring->idx].sequence - 1;
>> +
>>       if (seq >= cring->sequence) {
>>           spin_unlock(&ctx->ring_lock);
>>           return ERR_PTR(-EINVAL);
>
>
> _______________________________________________
> amd-gfx mailing list
> amd-gfx at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/amd-gfx