Re: [RFC PATCH 0/5] madvise MADV_DOEXEC

From: Jason Gunthorpe
Date: Fri Jul 31 2020 - 12:56:54 EST


On Fri, Jul 31, 2020 at 12:11:52PM -0400, Steven Sistare wrote:
> > Your preservation-across-exec use-case might or might not need the
> > VMA to be mapped at the same address.
>
> It does. qemu registers memory with vfio which remembers the va's in kernel
> metadata for the device.

Once the memory is registered with vfio the VA doesn't matter, vfio
will keep the iommu pointing at the same physical pages no matter
where they are mapped.

Jason