x86_64: Do not leak trampoline mapping into dom0's initial address space.

Signed-off-by: Keir Fraser <keir.fraser@citrix.com>

diff --git a/xen/arch/x86/domain_build.c b/xen/arch/x86/domain_build.c
index f530e27f5720f89c35c412923332f2fcb0193814..7279f20075474563f5902685e3a5b550f1d4587e 100644 (file)
--- a/xen/arch/x86/domain_build.c
+++ b/xen/arch/x86/domain_build.c
@@ -646,6 +646,7 @@ int __init construct_dom0(
         l4start = l4tab = page_to_virt(page);
     }
     copy_page(l4tab, idle_pg_table);
+    l4tab[0] = l4e_empty(); /* zap trampoline mapping */
     l4tab[l4_table_offset(LINEAR_PT_VIRT_START)] =
         l4e_from_paddr(__pa(l4start), __PAGE_HYPERVISOR);
     l4tab[l4_table_offset(PERDOMAIN_VIRT_START)] =