xen64: disable 32-bit syscall/sysenter if not supported.

[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 9d7a144028956cf518f6205b2e8e523ee8b94c69..9cce4a92aac0f5377514c56da5780449f2780429 100644 (file)
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -106,46 +106,46 @@ static __cpuinit int register_callback(unsigned type, const void *func)
 
 void __cpuinit xen_enable_sysenter(void)
 {
-       int cpu = smp_processor_id();
        extern void xen_sysenter_target(void);
        int ret;
+       unsigned sysenter_feature;
 
 #ifdef CONFIG_X86_32
-       if (!boot_cpu_has(X86_FEATURE_SEP)) {
-               return;
-       }
+       sysenter_feature = X86_FEATURE_SEP;
 #else
-       if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL &&
-           boot_cpu_data.x86_vendor != X86_VENDOR_CENTAUR) {
-               return;
-       }
+       sysenter_feature = X86_FEATURE_SYSENTER32;
 #endif
 
+       if (!boot_cpu_has(sysenter_feature))
+               return;
+
        ret = register_callback(CALLBACKTYPE_sysenter, xen_sysenter_target);
-       if(ret != 0) {
-               clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SEP);
-               clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SEP);
-       }
+       if(ret != 0)
+               setup_clear_cpu_cap(sysenter_feature);
 }
 
 void __cpuinit xen_enable_syscall(void)
 {
 #ifdef CONFIG_X86_64
-       int cpu = smp_processor_id();
        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("failed to set syscall: %d\n", ret);
-               clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SYSCALL);
-               clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SYSCALL);
-       } else {
+               printk(KERN_ERR "Failed to set syscall: %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)
-                       printk("failed to set 32-bit syscall: %d\n", ret);
+               if (ret != 0) {
+                       printk(KERN_INFO "Xen: 32-bit syscall not supported: disabling vdso\n");
+                       setup_clear_cpu_cap(X86_FEATURE_SYSCALL32);
+                       sysctl_vsyscall32 = 0;
+               }
        }
 #endif /* CONFIG_X86_64 */
 }