slow validate failure: static-plugins nonmoving_thr_sanity

Reproduce with

hadrian/build test --freeze1  --docs=none --flavour=slow-validate --test-speed=slow --only="static-plugins"

static-plugins: internal error: ASSERTION FAILED: file rts/CheckUnload.c, line 448

Stack trace:
                 0x4226bcc    set_initial_registers (rts/Libdw.c:294.57)
            0x7ff6f0df5fa8    dwfl_thread_getframes (/nix/store/fqklswrymlx110vj0sfmpq77yj99paiz-elfutils-0.186/lib/libdw-0.186.so)
            0x7ff6f0df5aeb    get_one_thread_cb (/nix/store/fqklswrymlx110vj0sfmpq77yj99paiz-elfutils-0.186/lib/libdw-0.186.so)
            0x7ff6f0df5e12    dwfl_getthreads (/nix/store/fqklswrymlx110vj0sfmpq77yj99paiz-elfutils-0.186/lib/libdw-0.186.so)
            0x7ff6f0df6357    dwfl_getthread_frames (/nix/store/fqklswrymlx110vj0sfmpq77yj99paiz-elfutils-0.186/lib/libdw-0.186.so)
                 0x4226ab6    libdwGetBacktrace (rts/Libdw.c:263.15)
                 0x41cd9ed    rtsFatalInternalErrorFn (rts/RtsMessages.c:175.30)
                 0x41cd5ac    barf (rts/RtsMessages.c:49.4)
                 0x41cd60f    errorBelch (rts/RtsMessages.c:68.5)
                 0x422341e    prepareUnloadCheck (rts/CheckUnload.c:450.5)
                 0x41f2883    GarbageCollect (rts/sm/GC.c:379.28)
                 0x41d59d8    scheduleDoGC (rts/Schedule.c:1861.5)
                 0x41d73bb    exitScheduler (rts/Schedule.c:2760.9)
                 0x41ce185    hs_exit_ (rts/RtsStartup.c:478.5)
                 0x41ce399    shutdownHaskellAndExit (rts/RtsStartup.c:666.9)
                 0x41cd4f7    barf (rts/RtsMessages.c:45.0)
                  0x410757    (null) (/run/user/1000/ghctest-derda1up/test   spaces/testsuite/tests/plugins/static-plugins.run/static-plugins)
            0x7ff6f0e901d7    __libc_start_call_main (/nix/store/ybkkrhdwdj227kr20vk8qnzqnmj7a06x-glibc-2.34-115/lib/libc.so.6)
            0x7ff6f0e90297    __libc_start_main@@GLIBC_2.34 (/nix/store/ybkkrhdwdj227kr20vk8qnzqnmj7a06x-glibc-2.34-115/lib/libc.so.6)
                  0x408011    _start (../sysdeps/x86_64/start.S:118.0)

    (GHC version 9.5.20220805 for x86_64_unknown_linux)
    Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug
*** unexpected failure for static-plugins(nonmoving_thr_sanity)