> please show what "mach cpu" "mach cpu 0\ntrace" give...

Sure:

cd0: sync (248.0ns offset 15), 8-bit (4.032MB/s) transfers
IPsec: Initialized Security Association Processing.
root on sd0a dumps on sd0b
root file system type: ffs
calling: cpu_boot_secondary_processors()
cpu0: booting secondary processors: cpu1
cpu0, curproc=0xf02bec80
calling: exec_init(1)
wakeup start_init_exec
calling: uvm_scheduler()
raise_ipi_wait_and_unlock(cpu0): couldn't ping cpu1
panic: cpu1: lockmgr: no context: lkp=0xf029653c interlkp=0x0 flags=0x1
Stopped at      cpu_Debugger+0x4:       jmpl            [%o7 + 0x8], %g0
db{1}> mach cpu
addr            cpuid   flags   curproc         fpproc
0xf6182000      0       e000           0x0             0x0
0xf61c2000      1       c000           0x0             0x0
db{1}> mach cpu 0
using cpu 0
db{1}> trace
db{1}> mach cpu 1
using cpu 1
db{1}> trace
_lockmgr(0xf029653c, 0x1, 0x0, 0xfffffffe, 0x92, 0xf024d5a0) at _lockmgr+0xf0
uvm_fault(0xf0296538, 0xf61c9000, 0x0, 0x2, 0x3de, 0x0) at uvm_fault+0x80
mem_access_fault4m(0x9, 0x3a6, 0xf61c9000, 0xf61c8f00, 0x0, 0x10) at mem_access_fault4m+0x2d8
memfault_sun4m(0xf61c8fb0, 0x80000000, 0x80000000, 0xf01fa280, 0x23b, 0xf02626f0) at memfault_sun4m+0xe4
sparc_interrupt44c(0xf064ff40, 0x0, 0x0, 0x0, 0x0, 0x0) at sparc_interrupt44c+0x164
cpu_hatch(0x0, 0x0, 0x0, 0x0, 0x0, 0x0) at cpu_hatch+0x88
db{1}> ps          
 PID             PPID       PGRP        UID S   FLAGS          COMMAND    WAIT
 6                  0          0          0 3 0xa0204         aiodoned aiodone
 5                  0          0          0 3 0xa0204          ioflush  syncer
 4                  0          0          0 3 0x20204           reaper  reaper
 3                  0          0          0 3 0xa0204       pagedaemon pgdaemo
 2                  0          0          0 3 0xa0204           esp0:0  sccomp
 1                  0          0          0 3 0x80004             init biowait
 0                 -1          0          0 3 0xa0204          swapper schedul
db{1}> 

--sjg