Re: [RFC PATCH v1 0/8] Arm Core Local Accelerator Driver

[Jason Gunthorpe]

On Fri, Jul 17, 2026 at 12:33:17PM +0100, Will Deacon wrote:

> first. So, at the moment, this just looks like a burden to me, especially
> as it appears to create a brand new, device-specific UAPI for what is
> ostensibly a form of SVA - something which the community is actively
> working on already.

Yeah, I think it was a mistake to hardwire the invalidation to the
CPU. It would fit much better into Linux if the invalidation was
separate and independently controllable with an option to follow the
CPU.

Then you could use a normal S2 page table through iommufd and not mess
with kvm. (though the VMID sharing with KVM for a BTM-like scheme was
never solved upstream)

I also wouldn't expect you to use vfio-mdev, if the devices are
discovered and known at boot then it should be a normal vfio driver.

Jason