On Mon, 23 Feb 2026 10:44:11 +0100 Igor Mammedov <[email protected]> wrote:
> On Mon, 23 Feb 2026 07:49:51 +0000 > Ankit Agrawal <[email protected]> wrote: > > > >> During creation of the VM's SRAT table, the generic initiator entries > > >> are added. Currently the order in the entries are not controllable from > > >> the qemu command. This is due to the fact that the code queries the > > >> object tree which may not be in the order objects were inserted. > > >> > > >> As a fix the patch maintains a GPtrArray of generic initiator objects > > >> that preserves their insertion order. Objects are automatically added > > >> to the array when initialized and removed when finalized. When building > > >> the SRAT table, objects are processed in the order they were first > > >> inserted. > > > > > > so question would be, why does it matter? > > > Is ther a requirement in spec for SRAT entries being put in a particular > > > order? > > > > Hi Igor, reposting my response. I'll make this information as part of the > > next > > version if and when I refresh. > > > > VM's Linux kernel parses the generic initiator (GI) structures present in > > the SRAT > > table sequentially in the order of their occurrence and assigns a numa node > > id when a new proximity domain (that is part of the GI structure) is > > encountered. > > A jumbled up entries in the VM's SRAT consequently results in the jumbled up > > sequence on numa nodes v/s the ones intended to be assigned through the > > qemu command line. This messes up the internode numa distances assignment > > through the qemu command line as the VM's view of the corresponding nodes > > is entirely different. > > Assuming that QEMU CLI is correctly defined, above looks very much like a > linux > kernel bug. > > Aka: if kernel is not mapping proximity ID to its internal node ids correctly > and then links them with something else entirely, it's kernel in wrong > and not ACPI tables QEMU provides. > > IMHO it should be fixed on kernel side. (unless you find statement in spec > that mandates the particular ordering in SRAT) > Ankit, can you give an example complete with table dumps please. I'm a little unsure on where things are getting scrambled. Everything should be keyed of PXM. Sounds like we have a bug somewhere but ordering shouldn't be relevant. Jonathan >
