x86: New feature flag XENFEAT_mmu_pt_update_preserve_ad.

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

diff --git a/xen/common/kernel.c b/xen/common/kernel.c
index 1ce1720afc5d335d0c04ec2b5caf5d6af5b42dd4..277ac21b64db07195fa18fe262ed079bbe240318 100644 (file)
--- a/xen/common/kernel.c
+++ b/xen/common/kernel.c
@@ -220,6 +220,10 @@ DO(xen_version)(int cmd, XEN_GUEST_HANDLE(void) arg)
                     (1U << XENFEAT_auto_translated_physmap);
             if ( supervisor_mode_kernel )
                 fi.submap |= 1U << XENFEAT_supervisor_mode_kernel;
+#ifdef CONFIG_X86
+            if ( !is_hvm_vcpu(current) )
+                fi.submap |= 1U << XENFEAT_mmu_pt_update_preserve_ad;
+#endif
             break;
         default:
             return -EINVAL;

diff --git a/xen/include/public/features.h b/xen/include/public/features.h
index d4b373ff17ac7820e646601c0b556e0a193e2df0..05fc5dc4644273c74aae21aac68a86e0bdefd399 100644 (file)
--- a/xen/include/public/features.h
+++ b/xen/include/public/features.h
@@ -56,6 +56,9 @@
  */
 #define XENFEAT_pae_pgdir_above_4gb        4
 
+/* x86: Does this Xen host support the MMU_PT_UPDATE_PRESERVE_AD hypercall? */
+#define XENFEAT_mmu_pt_update_preserve_ad  5
+
 #define XENFEAT_NR_SUBMAPS 1
 
 #endif /* __XEN_PUBLIC_FEATURES_H__ */