generic.MP stability on SMP QEMU?

I might experience something described in this thread:

https://mail-index.netbsd.org/port-sparc/2024/12/03/msg002823.html

But on qemu-emulated SS-20 with latest 10.1_stable kernel
https://nycdn.netbsd.org/pub/NetBSD-daily/netbsd-10/20251129160226Z/sparc/binary/kernel/

and 10.1 userland.

I thought it was lib/57628 but it was pulled up to 10 branch before 10.1
was cut?

https://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=57628

Note, I use self-compiled 32bit i586 qemu on Slackware


qemu-system-sparc -hda
/mnt/zip/home/guest/QEMU/sparc-netbsd-15g-compressed-r1.qcow2 -m 1536 -g
1024x768x24 -smp1 -acceltcg,thread=multi,tb-size=256 -M SS-20

if I set -smp to 2, 3 or 4 compiling bigger C++ things like re2c (needed by
ninja, needed by meson, needed by gobject-introspection, needed by gtk2)
results in hung build process (make install from /usr/pkgsrc)

I see some messages _lwp_ctl (?) can't allocate memory, but powerdown
usually works (on 10.1 kernel it resulted in some kernel panic in ffs, so
fsck was forced on new boot).

I hope I'll try to install tests.tgz and see if atf catch anything ...