Re: [PATCH] dma-debug: skip cacheline overlap tracking on cache-coherent architectures

[Christoph Hellwig]

On Mon, May 18, 2026 at 06:29:11PM +0500, Mikhail Gavrilov wrote:
> DIO from userspace is unfixable from the kernel side per that
> message; raid1 acknowledged as needing a fix Christoph didn't have.
> Two years on, those cases (plus dm-thin and io_uring polled tests
> from Ming Lei's report) still don't have an annotation path. This
> patch covers what annotation can't reach without preventing future
> annotation work.

It is not.  We could require direct I/O to/from devices that are
attached without DMA coherence to require cache line alignment.

Now that Keith pushed down the checking into the driver that's even
fairly easily doable.