Share memory as buffers

I use ARAVIS to capture video and push onto an OpenCV filter, and I do it on a ARM Cortex-A7 CPU, with VPU…
I use a ring buffer into share memory to send the images to the filter (in fact several filters at the same time and they run into another process).
The system run perfectly on a PC, but on the Cortex-A7, I have some glish on the image. A band of the middle of the image is placed on the top of the same image too.
I saw that Aravis use PF_PACKET socket with a ring buffer too.

Some body already saw this kind of trouble ?
I wonder if the PF_PACKET set directly the DMA and in this case it impossible to have a continous memory with share memory.
Can I set all arv buffers with my ring once ?

Best regards,
Marc from Bauges