Where does the default numa setting come from?

Question

when we run:

numactl --hardware

we can see the current status of numa setting.

However, it seems not set by Linux ( at least, I didn't add a parameter to set it ). Did it set by BIOS?

Answer 1

https://github.com/torvalds/linux/blob/59fc453b21f767f2fb0ff4dc0a947e9b9c9e6d14/arch/x86/mm/numa.c#L649

should parse SRAT which from BIOS.