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> unsigned long mask = ~0UL << (level * PAGETABLE_ORDER); > > - if ( !valid_recalc(l1, e) ) > - P2M_DEBUG("bogus recalc leaf at d%d:%lx:%u\n", > - p2m->domain->domain_id, gfn, level); > ot = p2m_flags_to_type(l1e_get_flags(e)); > nt = p2m_recalc_type_range(true, ot, p2m, gfn & mask, gfn | ~mask); > if ( nt != ot ) I'm afraid I neither understand why you make this change, nor why you then leave the other use of valid_recalc() in place. > @@ -538,9 +535,9 @@ int p2m_pt_handle_deferred_changes(uint64_t gpa) > */ > ASSERT(!altp2m_active(current->domain)); > > - p2m_lock(p2m); > + p2m_read_lock(p2m); > rc = do_recalc(p2m, PFN_DOWN(gpa)); > - p2m_unlock(p2m); > + p2m_read_unlock(p2m); > > return rc; > } How can this be safe, when do_recalc() involves p2m_next_level(), which may install new (intermediate) page tables? Jan