Re: [PATCH 1/2] mm/cma: remove unsupported gfp_mask parameter from cma_alloc()

[Joonsoo Kim]

2018-07-12 16:15 GMT+09:00 Christoph Hellwig <hch@xxxxxx>:
> On Thu, Jul 12, 2018 at 11:48:47AM +0900, Joonsoo Kim wrote:
>> One of existing user is general DMA layer and it takes gfp flags that is
>> provided by user. I don't check all the DMA allocation sites but how do
>> you convince that none of them try to use anything other
>> than GFP_KERNEL [|__GFP_NOWARN]?
>
> They use a few others things still like __GFP_COMP, __GPF_DMA or
> GFP_HUGEPAGE.  But all these are bogus as we have various implementations
> that can't respect them.  I plan to get rid of the gfp_t argument
> in the dma_map_ops alloc method in a few merge windows because of that,
> but it needs further implementation consolidation first.

Okay. If those flags are all, this change would be okay.

For the remind of this gfp flag introduction in cma_alloc(), see the
following link.

https://marc.info/?l=linux-mm&m=148431452118407

Thanks.