1.1 --- a/xen/arch/x86/mm/shadow/common.c	Sun Dec 31 12:26:42 2006 +0000
     1.2 +++ b/xen/arch/x86/mm/shadow/common.c	Tue Jan 02 10:57:50 2007 +0000
     1.3 @@ -3306,6 +3306,15 @@ int shadow_domctl(struct domain *d,
     1.4  
     1.5      case XEN_DOMCTL_SHADOW_OP_SET_ALLOCATION:
     1.6          shadow_lock(d);
     1.7 +        if ( sc->mb == 0 && shadow_mode_enabled(d) )
     1.8 +        {            
     1.9 +            /* Can't set the allocation to zero unless the domain stops using
    1.10 +             * shadow pagetables first */
    1.11 +            SHADOW_ERROR("Can't set shadow allocation to zero, domain %u"
    1.12 +                         " is still using shadows.\n", d->domain_id);
    1.13 +            shadow_unlock(d);
    1.14 +            return -EINVAL;
    1.15 +        }
    1.16          rc = sh_set_allocation(d, sc->mb << (20 - PAGE_SHIFT), &preempted);
    1.17          shadow_unlock(d);
    1.18          if ( preempted )