1 files changed, 17 insertions, 7 deletions

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 544eb74..dfbf70e 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -178,6 +178,7 @@ static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0;
 static void xen_cpuid(unsigned int *ax, unsigned int *bx,
 		      unsigned int *cx, unsigned int *dx)
 {
+	unsigned maskebx = ~0;
 	unsigned maskecx = ~0;
 	unsigned maskedx = ~0;
 
@@ -185,9 +186,16 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx,
 	 * Mask out inconvenient features, to try and disable as many
 	 * unsupported kernel subsystems as possible.
 	 */
-	if (*ax == 1) {
+	switch (*ax) {
+	case 1:
 		maskecx = cpuid_leaf1_ecx_mask;
 		maskedx = cpuid_leaf1_edx_mask;
+		break;
+
+	case 0xb:
+		/* Suppress extended topology stuff */
+		maskebx = 0;
+		break;
 	}
 
 	asm(XEN_EMULATE_PREFIX "cpuid"
@@ -197,6 +205,7 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx,
 		  "=d" (*dx)
 		: "0" (*ax), "2" (*cx));
 
+	*bx &= maskebx;
 	*cx &= maskecx;
 	*dx &= maskedx;
 }
@@ -1075,6 +1084,8 @@ asmlinkage void __init xen_start_kernel(void)
 	 * Set up some pagetable state before starting to set any ptes.
 	 */
 
+	xen_init_mmu_ops();
+
 	/* Prevent unwanted bits from being set in PTEs. */
 	__supported_pte_mask &= ~_PAGE_GLOBAL;
 	if (!xen_initial_domain())
@@ -1082,6 +1093,11 @@ asmlinkage void __init xen_start_kernel(void)
 
 	__supported_pte_mask |= _PAGE_IOMAP;
 
+#ifdef CONFIG_X86_64
+	/* Work out if we support NX */
+	check_efer();
+#endif
+
 	xen_setup_features();
 
 	/* Get mfn list */
@@ -1094,7 +1110,6 @@ asmlinkage void __init xen_start_kernel(void)
 	 */
 	xen_setup_stackprotector();
 
-	xen_init_mmu_ops();
 	xen_init_irq_ops();
 	xen_init_cpuid_mask();
 
@@ -1123,11 +1138,6 @@ asmlinkage void __init xen_start_kernel(void)
 
 	pgd = (pgd_t *)xen_start_info->pt_base;
 
-#ifdef CONFIG_X86_64
-	/* Work out if we support NX */
-	check_efer();
-#endif
-
 	/* Don't do the full vcpu_info placement stuff until we have a
 	   possible map and a non-dummy shared_info. */
 	per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];