>> 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

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