X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=arch%2Fx86%2Fxen%2Fsetup.c;h=b6acc3a0af46d0adeb44a99a8b8d78e1ef8c5140;hb=8ffa5b65968262ba6bb046329972791c0d960745;hp=9d7a144028956cf518f6205b2e8e523ee8b94c69;hpb=6fcac6d305e8238939e169f4c52e8ec8a552a31f;p=linux-2.6-omap-h63xx.git

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 9d7a1440289..b6acc3a0af4 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -83,12 +83,16 @@ 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)
 {
-#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
-	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
 }
@@ -106,46 +110,43 @@ 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 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)
-			printk("failed to set 32-bit syscall: %d\n", ret);
+			setup_clear_cpu_cap(X86_FEATURE_SYSCALL32);
 	}
 #endif /* CONFIG_X86_64 */
 }