2 files changed, 16 insertions, 12 deletions

diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
index 172438f86a02..7410640db173 100644
--- a/arch/x86/xen/Makefile
+++ b/arch/x86/xen/Makefile
@@ -5,6 +5,10 @@ CFLAGS_REMOVE_time.o = -pg
 CFLAGS_REMOVE_irq.o = -pg
 endif
 
+# Make sure early boot has no stackprotector
+nostackp := $(call cc-option, -fno-stack-protector)
+CFLAGS_enlighten.o              := $(nostackp)
+
 obj-y           := enlighten.o setup.o multicalls.o mmu.o irq.o \
                         time.o xen-asm.o xen-asm_$(BITS).o \
                         grant-table.o suspend.o
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 0a1700a2be9c..eb33aaa8415d 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -215,6 +215,7 @@ static __init void xen_init_cpuid_mask(void)
                           (1 << X86_FEATURE_ACPI));  /* disable ACPI */
 
         ax = 1;
+        cx = 0;
         xen_cpuid(&ax, &bx, &cx, &dx);
 
         /* cpuid claims we support xsave; try enabling it to see what happens */
@@ -974,10 +975,6 @@ asmlinkage void __init xen_start_kernel(void)
 
         xen_domain_type = XEN_PV_DOMAIN;
 
-        BUG_ON(memcmp(xen_start_info->magic, "xen-3", 5) != 0);
-
-        xen_setup_features();
-
         /* Install Xen paravirt ops */
         pv_info = xen_info;
         pv_init_ops = xen_init_ops;
@@ -986,8 +983,15 @@ asmlinkage void __init xen_start_kernel(void)
         pv_apic_ops = xen_apic_ops;
         pv_mmu_ops = xen_mmu_ops;
 
-        xen_init_irq_ops();
+#ifdef CONFIG_X86_64
+        /*
+         * Setup percpu state.  We only need to do this for 64-bit
+         * because 32-bit already has %fs set properly.
+         */
+        load_percpu_segment(0);
+#endif
 
+        xen_init_irq_ops();
         xen_init_cpuid_mask();
 
 #ifdef CONFIG_X86_LOCAL_APIC
@@ -997,6 +1001,8 @@ asmlinkage void __init xen_start_kernel(void)
         set_xen_basic_apic_ops();
 #endif
 
+        xen_setup_features();
+
         if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) {
                 pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start;
                 pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit;
@@ -1004,13 +1010,6 @@ asmlinkage void __init xen_start_kernel(void)
 
         machine_ops = xen_machine_ops;
 
-#ifdef CONFIG_X86_64
-        /*
-         * Setup percpu state.  We only need to do this for 64-bit
-         * because 32-bit already has %fs set properly.
-         */
-        load_percpu_segment(0);
-#endif
         /*
          * The only reliable way to retain the initial address of the
          * percpu gdt_page is to remember it here, so we can go and
@@ -1061,6 +1060,7 @@ asmlinkage void __init xen_start_kernel(void)
         /* set up basic CPUID stuff */
         cpu_detect(&new_cpu_data);
         new_cpu_data.hard_math = 1;
+        new_cpu_data.wp_works_ok = 1;
         new_cpu_data.x86_capability[0] = cpuid_edx(1);
 #endif