Re: [PATCH] swiotlb: suppress warning when __GFP_NOWARN is set v5

[Christian KÃnig]

Am 04.01.2018 um 14:29 schrieb Christoph Hellwig:
> > @@ -713,6 +713,7 @@ void *
> >   swiotlb_alloc_coherent(struct device *hwdev, size_t size,
> >   		       dma_addr_t *dma_handle, gfp_t flags)
> >   {
> > +	bool warn = !(flags & __GFP_NOWARN);
> This is still wrong.  __GFP_NOWARN has no meaning for DMA coherent
> allocations, and if a driver expects it to do anything it's doing it
> wrong.  This needs to check for DMA_ATTR_NO_WARN, and thus get the attrs
> passed.

I perfectly agree on that, but this is for stable kernel backports. 
Because of this I want to keep the footprint as low as possible.

When your patchset to clean that up lands for 4.16 I have no problem 
changing that.

But till then I think we should just work on suppress the warning for now.

Regards,
Christian.