Re: [PATCH] dma-direct: Set SG_DMA_SWIOTLB flag for dma-direct

[T.J. Mercier]

On Mon, May 6, 2024 at 10:43 PM Christoph Hellwig <hch@xxxxxx> wrote:
>
> On Mon, May 06, 2024 at 09:39:53AM -0700, T.J. Mercier wrote:
> > > You should not check, you simply must handle it by doing the proper
> > > DMA API based ownership management.
> >
> > That doesn't really work for uncached buffers.
>
> What uncached buffers?

For example these ones:
https://android.googlesource.com/kernel/common/+/refs/heads/android-mainline/drivers/dma-buf/heaps/system_heap.c#141

Vendors have their own drivers that also export uncached buffers in a
similar way.