13902 Fix for 13717 may break 8-disk raidz2
13915 installctx() blocking allocate causes problems
Portions contributed by: Jerry Jelinek <gjelinek@gmail.com>
Change-Id: I934d69946cec42630fc541fa8c7385b862b69ca2

*** 2214,2224 ****
  
          vtc.vtc_vm = vm;
          vtc.vtc_vcpuid = vcpuid;
          vtc.vtc_status = 0;
          installctx(curthread, &vtc, vmm_savectx, vmm_restorectx, NULL, NULL,
!             NULL, vmm_freectx);
  
          error = vm_entry_actions(vm, vcpuid, entry, vme);
          if (error != 0) {
                  goto exit;
          }
--- 2214,2224 ----
  
          vtc.vtc_vm = vm;
          vtc.vtc_vcpuid = vcpuid;
          vtc.vtc_status = 0;
          installctx(curthread, &vtc, vmm_savectx, vmm_restorectx, NULL, NULL,
!             NULL, vmm_freectx, NULL);
  
          error = vm_entry_actions(vm, vcpuid, entry, vme);
          if (error != 0) {
                  goto exit;
          }