On Fri, Sep 30, 2022 at 11:33 AM Catalin Marinas <catalin.marinas@xxxxxxx> wrote: > > I started refreshing the series but I got stuck on having to do bouncing > for small buffers even if when they go through the iommu (and I don't > have the set up to test it yet). May I suggest doing that "force bouncing" and "change kmalloc to have a 8-byte minalign" to be the two first commits? IOW, if we force bouncing for unaligned DMA, then that *should* mean that allocation alignment is no longer a correctness issue, it's purely a performance one due to the bouncing. So then the rest of the series should be about "ok, this is actually a hot enough allocation that I want to force alignment", and be purely about performance, not correctness. No? Linus