Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg...

[linux-2.6-omap-h63xx.git] / arch / x86 / xen / setup.c

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 2341492bf7a056743097e06bfabd0b8c01f7436f..82517e4a752a19049c0177768851f48a1190a639 100644 (file)
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -16,6 +16,7 @@
 #include <asm/xen/hypervisor.h>
 #include <asm/xen/hypercall.h>
 
+#include <xen/interface/callback.h>
 #include <xen/interface/physdev.h>
 #include <xen/features.h>
 
@@ -68,6 +69,24 @@ static void __init fiddle_vdso(void)
        *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
 }
 
+void xen_enable_sysenter(void)
+{
+       int cpu = smp_processor_id();
+       extern void xen_sysenter_target(void);
+       /* Mask events on entry, even though they get enabled immediately */
+       static struct callback_register sysenter = {
+               .type = CALLBACKTYPE_sysenter,
+               .address = { __KERNEL_CS, (unsigned long)xen_sysenter_target },
+               .flags = CALLBACKF_mask_events,
+       };
+
+       if (!boot_cpu_has(X86_FEATURE_SEP) ||
+           HYPERVISOR_callback_op(CALLBACKOP_register, &sysenter) != 0) {
+               clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SEP);
+               clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SEP);
+       }
+}
+
 void __init xen_arch_setup(void)
 {
        struct physdev_set_iopl set_iopl;
@@ -82,6 +101,8 @@ void __init xen_arch_setup(void)
        HYPERVISOR_set_callbacks(__KERNEL_CS, (unsigned long)xen_hypervisor_callback,
                                 __KERNEL_CS, (unsigned long)xen_failsafe_callback);
 
+       xen_enable_sysenter();
+
        set_iopl.iopl = 1;
        rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
        if (rc != 0)