[2/2] media: venus: venc: fix bytesused v4l2_plane field

Message ID 20171009122458.3053-2-stanimir.varbanov@linaro.org
State New
Headers show
Series
  • Untitled series #4781
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Commit Message

Stanimir Varbanov Oct. 9, 2017, 12:24 p.m.
This fixes wrongly filled bytesused field of v4l2_plane structure
by include data_offset in the plane, Also fill data_offset and
bytesused for capture type of buffers only.

Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>

---
 drivers/media/platform/qcom/venus/venc.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

-- 
2.11.0

Comments

Hans Verkuil Oct. 9, 2017, 12:31 p.m. | #1
On 09/10/17 14:24, Stanimir Varbanov wrote:
> This fixes wrongly filled bytesused field of v4l2_plane structure

> by include data_offset in the plane, Also fill data_offset and

> bytesused for capture type of buffers only.

> 

> Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>

> ---

>  drivers/media/platform/qcom/venus/venc.c | 9 +++++----

>  1 file changed, 5 insertions(+), 4 deletions(-)

> 

> diff --git a/drivers/media/platform/qcom/venus/venc.c b/drivers/media/platform/qcom/venus/venc.c

> index 6f123a387cf9..9445ad492966 100644

> --- a/drivers/media/platform/qcom/venus/venc.c

> +++ b/drivers/media/platform/qcom/venus/venc.c

> @@ -963,15 +963,16 @@ static void venc_buf_done(struct venus_inst *inst, unsigned int buf_type,

>  	if (!vbuf)

>  		return;

>  

> -	vb = &vbuf->vb2_buf;

> -	vb->planes[0].bytesused = bytesused;

> -	vb->planes[0].data_offset = data_offset;

> -

>  	vbuf->flags = flags;

>  

>  	if (type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {

> +		vb = &vbuf->vb2_buf;

> +		vb2_set_plane_payload(vb, 0, bytesused + data_offset);

> +		vb->planes[0].data_offset = data_offset;

>  		vb->timestamp = timestamp_us * NSEC_PER_USEC;

>  		vbuf->sequence = inst->sequence_cap++;

> +

> +		WARN_ON(vb2_get_plane_payload(vb, 0) > vb2_plane_size(vb, 0));


It's good to have this, but this really should never happen. Because if it is,
then you'll have a memory overwrite. I hope the DMA engine will prevent this?

Just wondering how this works.

The patch looks good otherwise, but that WARN_ON is a bit scary.

Regards,

	Hans

>  	} else {

>  		vbuf->sequence = inst->sequence_out++;

>  	}

>
Stanimir Varbanov Oct. 9, 2017, 10:17 p.m. | #2
Hans,

On  9.10.2017 15:31, Hans Verkuil wrote:
> On 09/10/17 14:24, Stanimir Varbanov wrote:

>> This fixes wrongly filled bytesused field of v4l2_plane structure

>> by include data_offset in the plane, Also fill data_offset and

>> bytesused for capture type of buffers only.

>>

>> Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>

>> ---

>>   drivers/media/platform/qcom/venus/venc.c | 9 +++++----

>>   1 file changed, 5 insertions(+), 4 deletions(-)

>>

>> diff --git a/drivers/media/platform/qcom/venus/venc.c b/drivers/media/platform/qcom/venus/venc.c

>> index 6f123a387cf9..9445ad492966 100644

>> --- a/drivers/media/platform/qcom/venus/venc.c

>> +++ b/drivers/media/platform/qcom/venus/venc.c

>> @@ -963,15 +963,16 @@ static void venc_buf_done(struct venus_inst *inst, unsigned int buf_type,

>>   	if (!vbuf)

>>   		return;

>>   

>> -	vb = &vbuf->vb2_buf;

>> -	vb->planes[0].bytesused = bytesused;

>> -	vb->planes[0].data_offset = data_offset;

>> -

>>   	vbuf->flags = flags;

>>   

>>   	if (type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {

>> +		vb = &vbuf->vb2_buf;

>> +		vb2_set_plane_payload(vb, 0, bytesused + data_offset);

>> +		vb->planes[0].data_offset = data_offset;

>>   		vb->timestamp = timestamp_us * NSEC_PER_USEC;

>>   		vbuf->sequence = inst->sequence_cap++;

>> +

>> +		WARN_ON(vb2_get_plane_payload(vb, 0) > vb2_plane_size(vb, 0));

> 

> It's good to have this, but this really should never happen. Because if it is,

> then you'll have a memory overwrite. I hope the DMA engine will prevent this? >

> Just wondering how this works.

> 

> The patch looks good otherwise, but that WARN_ON is a bit scary.


Infact it is not so scary as it looks like, the IOMMU will catch this 
and generate a fault. So most probably we will never come to the WARN, 
thus the warning is pointless so will delete it.

regards,
Stan

Patch

diff --git a/drivers/media/platform/qcom/venus/venc.c b/drivers/media/platform/qcom/venus/venc.c
index 6f123a387cf9..9445ad492966 100644
--- a/drivers/media/platform/qcom/venus/venc.c
+++ b/drivers/media/platform/qcom/venus/venc.c
@@ -963,15 +963,16 @@  static void venc_buf_done(struct venus_inst *inst, unsigned int buf_type,
 	if (!vbuf)
 		return;
 
-	vb = &vbuf->vb2_buf;
-	vb->planes[0].bytesused = bytesused;
-	vb->planes[0].data_offset = data_offset;
-
 	vbuf->flags = flags;
 
 	if (type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
+		vb = &vbuf->vb2_buf;
+		vb2_set_plane_payload(vb, 0, bytesused + data_offset);
+		vb->planes[0].data_offset = data_offset;
 		vb->timestamp = timestamp_us * NSEC_PER_USEC;
 		vbuf->sequence = inst->sequence_cap++;
+
+		WARN_ON(vb2_get_plane_payload(vb, 0) > vb2_plane_size(vb, 0));
 	} else {
 		vbuf->sequence = inst->sequence_out++;
 	}