Re: [PATCH] dmaengine: dmatest: Remove use of VLAs

[okaya]

On 2018-04-09 19:14, 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.

I think allocation is a better choice.

> Thanks,
> Laura
>
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