print kernel stacktrace for exceptions in kernel

fpu alignment check feature, checksum feature

kernel/system/do_mcontext.c

@@ -86,6 +86,7 @@ PUBLIC int do_setmcontext(struct proc * caller, message * m_ptr)
 	rp->p_misc_flags |= MF_FPU_INITIALIZED;
 	memcpy(rp->p_fpu_state.fpu_save_area_p, &(mc.mc_fpu_state),
 								FPU_XFP_SIZE);
+	fpu_makechecksum(rp);
   } else
 	rp->p_misc_flags &= ~MF_FPU_INITIALIZED;
   /* force reloading FPU in either case */