On Mon, Nov 16, 2020 at 9:33 AM Christoph Hellwig <hch@xxxxxx> wrote: > > On Sat, Nov 14, 2020 at 03:07:20PM -0500, Jonathan Marek wrote: > > qcom's vulkan driver has nonCoherentAtomSize=1, and it looks like > > dma_sync_single_for_cpu() does deal in some way with the partial cache line > > case, although I'm not sure that means we can have a nonCoherentAtomSize=1. > > No, it doesn't. You need to ensure ownership is managed at > dma_get_cache_alignment() granularity. my guess is nonCoherentAtomSize=1 only works in the case of cache coherent buffers BR, -R
