Re: [PATCH v1 1/1] hw/acpi/pci.c: preserve generic initiator insertion order

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Feb 24, 2026 at 04:22:56PM +0000, Ankit Agrawal wrote:
> >> Now the kernel parse it in the sequence of their occurrence. A jumbled up
> >> sequence thus results in a jumbled up assignment.
> >
> > But what is the actual failure mode here? So the numa IDs are all in a
> > weird order, what goes wrong from that?
> 
> This interferes with the ability to replicate the numa distance topology
> on host in the VM through qemu command line.
> 
> E.g. consider a NUMA system with 2 sockets each with a GPU.
> 0,1 are the node ids for the sysmem on socket 0,1 respectively and
> 2,3 are the node ids for the GPU memory on socket 0,1 respectively
> dist(0,2) = X
> dist(0,3) = Y
> 
> If we try to replicate this for the VM by passing qemu arguments with
> 4 numa nodes and assign numa distances similar to host, and for the
> sake of example qemu mixes up by putting GI for 3 over 2. The SLIT
> which sets up the distances do it considering the original order in the
> qemu command line.
> https://github.com/qemu/qemu/blob/stable-10.2/hw/acpi/aml-build.c#L2040
> 
> This would lead to a different numa config in terms of distance within
> the VM that the one intended through the qemu command line.
> 
> Thanks
> Ankit Agrawal

but this is not how SLIT is formatted, is it? it does not refer to
entries by their location in the table, or am I confused?