dmaengine: dmatest: Remove use of VLAs

[Vinod Koul <vinod.koul@intel.com>]

On Mon, Apr 09, 2018 at 04:14:20PM -0700, Laura Abbott wrote:
> On 04/09/2018 03:48 PM, Sinan Kaya wrote:
> >On 4/9/2018 5:06 PM, Laura Abbott wrote:
> >>+			/* dst_cnt can't be more than u8 */
> >>+			dma_addr_t dma_pq[255];
> >
> >This is 2k stack space on 64 bit architectures. Isn't that a lot?
> >
> 
> Depends on your definition of 'a lot'. My assumption was that
> since this was a test module there would be some willingness
> to be a bit more generous. The problem is the array size is
> based off of the parameters passed in, although oddly enough
> it's based off of the minimum of two variables. If you have
> a suggestion for a tighter bound we can use that. Another
> option is to just switch to allocating the array with kmalloc.
> That might be reasonable here since there's other setup
> that happens before the test starts.

Being a test module I don't think I would have too many qualms with current
approach :) said that kmalloc approach seems reasonable too..

Thanks