1 files changed, 59 insertions, 20 deletions

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index e0a39595bde3..b6acc3a0af46 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -83,30 +83,72 @@ static void xen_idle(void)
 
 /*
  * Set the bit indicating "nosegneg" library variants should be used.
+ * We only need to bother in pure 32-bit mode; compat 32-bit processes
+ * can have un-truncated segments, so wrapping around is allowed.
  */
 static void __init fiddle_vdso(void)
 {
-	extern const char vdso32_default_start;
-	u32 *mask = VDSO32_SYMBOL(&vdso32_default_start, NOTE_MASK);
+#ifdef CONFIG_X86_32
+	u32 *mask;
+	mask = VDSO32_SYMBOL(&vdso32_int80_start, NOTE_MASK);
 	*mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
+	mask = VDSO32_SYMBOL(&vdso32_sysenter_start, NOTE_MASK);
+	*mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
+#endif
 }
 
-void xen_enable_sysenter(void)
+static __cpuinit int register_callback(unsigned type, const void *func)
 {
-	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 },
+	struct callback_register callback = {
+		.type = type,
+		.address = XEN_CALLBACK(__KERNEL_CS, func),
 		.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);
+	return HYPERVISOR_callback_op(CALLBACKOP_register, &callback);
+}
+
+void __cpuinit xen_enable_sysenter(void)
+{
+	extern void xen_sysenter_target(void);
+	int ret;
+	unsigned sysenter_feature;
+
+#ifdef CONFIG_X86_32
+	sysenter_feature = X86_FEATURE_SEP;
+#else
+	sysenter_feature = X86_FEATURE_SYSENTER32;
+#endif
+
+	if (!boot_cpu_has(sysenter_feature))
+		return;
+
+	ret = register_callback(CALLBACKTYPE_sysenter, xen_sysenter_target);
+	if(ret != 0)
+		setup_clear_cpu_cap(sysenter_feature);
+}
+
+void __cpuinit xen_enable_syscall(void)
+{
+#ifdef CONFIG_X86_64
+	int ret;
+	extern void xen_syscall_target(void);
+	extern void xen_syscall32_target(void);
+
+	ret = register_callback(CALLBACKTYPE_syscall, xen_syscall_target);
+	if (ret != 0) {
+		printk(KERN_ERR "Failed to set syscall callback: %d\n", ret);
+		/* Pretty fatal; 64-bit userspace has no other
+		   mechanism for syscalls. */
 	}
+
+	if (boot_cpu_has(X86_FEATURE_SYSCALL32)) {
+		ret = register_callback(CALLBACKTYPE_syscall32,
+					xen_syscall32_target);
+		if (ret != 0)
+			setup_clear_cpu_cap(X86_FEATURE_SYSCALL32);
+	}
+#endif /* CONFIG_X86_64 */
 }
 
 void __init xen_arch_setup(void)
@@ -120,10 +162,12 @@ void __init xen_arch_setup(void)
 	if (!xen_feature(XENFEAT_auto_translated_physmap))
 		HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_pae_extended_cr3);
 
-	HYPERVISOR_set_callbacks(__KERNEL_CS, (unsigned long)xen_hypervisor_callback,
-				 __KERNEL_CS, (unsigned long)xen_failsafe_callback);
+	if (register_callback(CALLBACKTYPE_event, xen_hypervisor_callback) ||
+	    register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback))
+		BUG();
 
 	xen_enable_sysenter();
+	xen_enable_syscall();
 
 	set_iopl.iopl = 1;
 	rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
@@ -143,11 +187,6 @@ void __init xen_arch_setup(void)
 
 	pm_idle = xen_idle;
 
-#ifdef CONFIG_SMP
-	/* fill cpus_possible with all available cpus */
-	xen_fill_possible_map();
-#endif
-
 	paravirt_disable_iospace();
 
 	fiddle_vdso();