On Wed, Mar 9, 2016 at 11:16 AM, Ran Shalit [off-list ref] wrote:

Hello,

I have some sample code which uses 2 test application:
1. test application in kernel , which allocates buffer using kmalloc
(GFP_KERNEL)
2. test application in userspace which allocates buffer using malloc

just to add that in the case (2) of userspace, the kernel driver use
copy_from_user before dma transfer.

In both cases the buffers are DMA through PCI.
I don't understand how is it that the buffers are allocated with
malloc/kmalloc for DMA.
Is there any idea ?

Regards,
Ran