xen64: implement xen_load_gs_index()

xen-64: implement xen_load_gs_index()

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 11 insertions, 0 deletions

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 52f2292672c4..3b6b7fcf5b55 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -385,6 +385,14 @@ static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
                 loadsegment(gs, 0);
 }
 
+#ifdef CONFIG_X86_64
+static void xen_load_gs_index(unsigned int idx)
+{
+        if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx))
+                BUG();
+}
+#endif
+
 static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
                                 const void *ptr)
 {
@@ -1063,6 +1071,9 @@ static const struct pv_cpu_ops xen_cpu_ops __initdata = {
         .load_gdt = xen_load_gdt,
         .load_idt = xen_load_idt,
         .load_tls = xen_load_tls,
+#ifdef CONFIG_X86_64
+        .load_gs_index = xen_load_gs_index,
+#endif
 
         .store_gdt = native_store_gdt,
         .store_idt = native_store_idt,