On Mon, Aug 10, 2026 at 01:37:11PM +0200, Marek Szyprowski wrote: > On 10.08.2026 12:20, Will Deacon wrote: > > On Mon, Aug 10, 2026 at 02:59:42PM +0530, Aneesh Kumar K.V wrote: > >> Marek Szyprowski <[email protected]> writes: > >> > >>> On 07.08.2026 20:20, Jason Gunthorpe wrote: > >>>> On Fri, Aug 07, 2026 at 06:13:49PM +0000, Mostafa Saleh wrote: > >>>>> But the whole thing is best effort anyway, the kernel picks > >>>>> IO_TLB_DEFAULT_SIZE which does not depend on the system topology or > >>>>> how many devices or how much DMA they do. > >>>>> SWIOTLB memory is wasted if unused so we should be careful around > >>>>> that as it would be the other way around and users would have to > >>>>> decrease it manually. > >>>> Yeah, it is why the arch code shouldn't really be sizing it directly, > >>>> it should be done in common code and, yes, we are probably going to > >>>> have to do something alot smarter to have the common code better > >>>> auto-tune this for the CC case.. > >>> What about the $subject patch? I assume that it is still needed to > >>> > >>> restore the behavior that was altered by the "[PATCH v8 00/23] > >>> > >>> dma-mapping: Track shared DMA state through direct, pool and swiotlb > >>> > >>> paths?" patchset? > >>> > >> I would request that we pick this patch to fix the regression described > >> in https://lore.kernel.org/all/[email protected]/. > > I really don't think we need it. CCA hardware isn't exactly widespread > > and the KVM host side patches don't appear close to being merged. > > Does this mean that the branch for-next/coco [1] won't go to v7.3-rc1?
Argh, no, I'm definitely planning to send that! I'm just saying that this specific fixup patch (which is a PATCH sent in reply to another patch in the middle of a series...): https://lore.kernel.org/all/[email protected]/ isn't something we should take for the upcoming merge window. There are better, alternative ways to tackle the issue (as discussed in the thread) and it's really not as urgent as Aneesh is trying to make it sound. Will
