linux-image-amd64: failed to bring up processor 192

[Jeffrey Mark Siskind <qobi@qobi.org>]

I purchased a new server based on the Supermicro AS-8125GS-TNHR. It
has two EPYC 9654 processors. Each processor has 96 cores and 192 hyperthreads.
Thus the system as a whole has 192 cores and 384 hyperthreads. I run
Debian stable bookworm. When first installed, it ran kernel
6.1.0.12. That kernel found all 384 "CPUs". All were reported in /proc/cpuinfo.
I subsequently did an apt upgrade which upgraded to 6.1.0.13. Upon
boot, dmesg -lerr reports:

   root@poto:~# dmesg -lerr
   [   11.080833] smpboot: do_boot_cpu failed(-1) to wakeup CPU#192

Further, /proc/cpuinfo is missing processor 192.

I subsequently installed 6.4.0-0-deb12.2-amd64 from bookwork
backports. The issue still occurs. If I boot 6.1.0.12 I do not get the issue.

There are other reasons I cannot run 6.1.0.12 that I will describe in
a different bug report.

    Thanks,
    Jeff (http: //engineering.purdue.edu/~qobi)